Suter clutch still slipping

Finally got out yesterday to test the new plates I put in my Suter clutch. Seemed OK, got engine warm, found a fast bit of A road and started trying the bike at full throttle in all the gears. Slip still there.

So now I have to think logically about what can be causing this. Any thoughts about what I should try first?

Background is that it's an '07 SD with a Suter slipper clutch which I fitted myself about three years ago. Original clutch has done 10,000 miles. (the Suter clutch uses the stock SD plates). Has worked faultlessly until about a month ago. Started noticing that it was slipping at max revs - mostly in 4th and 5th at high speeds on motorways.

Bought a new set of KTM friction plates a few weeks ago and fitted them last weekend. The old plates did not look too worn out and the metal plates were not discoloured. I didn't measure their thickness as I didn't have the wear tolerance numbers to hand but I have since measured the old friction plates and they do seem to be within the acceptable limits.

OIL.
I had the bike given an oil change at about the same time problem started and so yesterday popped into the dealer who did it to ask them what oil they put in and was told 10/50 fully synthetic and that it would not be the oil that was causing the slip - but I could try changing it to see if it makes a difference.

MASTER AND SLAVE CYLINDER
Is it possible that the hydraulic side of the clutch actuation can put pressure on the clutch so that it's never fully engaged? (like an old cable clutch with the cable adjusted too tight) I don't see how this is possible really but....?

METAL PLATES
These could be worn out but I can't see how this could be possible if the friction plates seem OK.

CLUTCH SPRING
The Suter clutch does not have conventional springs - it uses a flat metal plate. Could this have worn out? There are two other plates in the kit that offer different levels of slip so I could try changing them over to see if this cures the problem.

ANTI_HOPPING MECHANISM
The most obvious cause is that somehow the slipper part of the clutch mechanism is somehow not returning to fully engaged and is always holding the plates apart a tiny fraction. But I'm just not too familiar with the way this clutch works to visualise how this might be happening. When you take the front of the clutch off to replace the plates there isn't anything obvious to see. Maybe I need to take off the whole outer basket as well and have a look at everything. Maybe there's a service routine that should be done? I can't find anything on the net and because I got the clutch second hand I don't have the original paperwork or any instructions.

Does anyone have any first hand experience of the Suter clutch? It's the same part as the KTM hardparts anti-hopping clutch I think.

Any help appreciated - I was thinking about Brands this coming Thursday but can't go without a clutch.

Logic says its the oil, first thing i would do would be to get rid of it, complete change with new filters to the last good oil you used, you wont get rid of it all that will need a couple of changes...

next clean up the clutch plates,you must get rid of all the dodgy oil, a good blast both sides with brake cleaner, frictions and steels,let them dry then soak the frictions for an hour or two in your GOOD oil,

put it back together and hopefully that will be problem solved

Thanks for this, I will change the oil first because it's the easiest thing to do and maybe will be the problem- it's the first thing I started to be suspicious about. mainly because I don't really trust P&H Motorcycles in Crawley - they maybe a kTM dealer but don't seem to know anything about the bikes. I just checked their invoice/receipt and the oil they used is shown as 10/40 Syntec 4.(Not 10/50 llike they told me). When you google this it comes up as a Putoline product. Not sure of the quality of this but it does say suitable for all modern clutches etc.

http://www.putoline.com/en/products/cat ... c-4-10w40/

Yeah dealers are never going to own up to doing anything wrong if you have problems.......

I would still suspect the oil, it may not even be whats on the invoice in the engine!

As soon as I read your first post on this I thought.... OIL.....

I have had similar problems with the TLs which has a slipper type clutch, dealer service, Mobil full synthetic, clutch slip...... strip the clutch, clean off the dodgy oil... flush the motor with fresh Motul 5100 oil problem solved

Good luck

I have also found this Suter instructions manual on the internet which has a fault finding page. (Page 24)
http://www.suterclutch.com/downloads/SR ... chr_V2.PDF
Interesting thing is that they say that clutch might slip due to increase in power over standard engine and my bike has gone from 118BHP to nearly 127BHP over the last three years. They say to just go up in spring strength to compensate for this so I will try this as well. But they also say check the oil too.

I think its the same slipper clutch they recommend for the SDR so it should cope ......

I would also clean the clutch oil jet out.

If the clutch pack is in good condition & within the Suter measurement spec & you have changed the oil & the clutch jet is clean, go 400n or 600n up on the pressure plate diaphram (Link Below), I run one up from standard on my SMT slipper & have never had any problems with slip & I have around the same HP as you. http://suterclutch.com/forge/shop.cgi?c ... ategory=73

PIcs of pressure plate please.
Mine was worn and slipped like crazy with little warning before it got there.
The tolerance for the wear is almost non existent it is so minimal.
I will search for old threads I posted on this.

Perhaps some of you who purchased one of my clutches has sorted this problem by now?

Hey Bic! I realise that you were the first to answer when I posted my problems in Sept. 2010.
Found the post:

viewtopic.php?f=1&t=14035&p=161957#p161957

Great find mate! Great thread - I'd forgot about that one completely but it has many of the facts I'm looking for. I'm going to measure the new stack and see about getting a new main pressure plate/spring with a bit more strength. Oh, and first change the oil.

Something I read in that thread is bugging me! There's a letter from Suter to Jody in response to his problems. They say that if the six bolts that hold on the outer pressure plate do not have the washers then the clutch will slip. When you look at the Suter parts diagram it's the washers that are number 17. I couldn't remember if mine had them on or not but just checked the photos I took and there do not appear to be any washers on. This means that they are too long and hit the small anti-hopping pressure plate and cause clutch slip. Maybe this is something I will look into.

you will need the washers, they are part number 17. I would think that your problem is related to an incorrect assembly.
There is also a small preassure ring at the very end of the whole clutch pack, if this one is missing you also run into problems.
Usually its missed becaused it sticks with the oil to the old clutch basket when you change over to the slipper clutch.
The installation manual of the Sutter clutch is also not too bad and in english, review all steps.

What's the part number on the exploded Suter parts diagram for this pressure ring? Not sure which part you refer to.

Check the engine sparepart manual section 4.9. There is the clutch explained. The washer is item no. 11 and 12 part number 60032035000 and 60032034000. They should sit at the very end of the complete clutch pack. When you pull the pack out they usually stick to the clutch hub and thats why they are often missed.

What, no search?

Stated previously, and here again: The diaphram spring that comes with the Suter is inadequate. I have posted what does work in other threads.

And yes, like any spring, the diaphram spring can yield over time.

nope, 130 HP at the rear wheel and it works like a charm since several thousand miles without any issues.
Of course a spring will age over time and if the clutch disks are worn out its a good idea to change the springs also, but if its in good shape it works like it should.

never checked which spring Sutter provides. Several were also used in the Superduke battle as only Powerparts were allowed.
Mine is actually a used battle one and nobody had a problem with the clutch itself. The issue which came up using it on the race track
every weekend was that the friction discs show massive wear. This came up unexpected quick and lots of drivers sold the Sutter and
went back the OEM clutch. What i'm saying here is that the clutch itself has no embedded problem in construction, but to make
it work like it should proper assembly and overall thickness of the clutch package is key. The way the clutch work depends
on this parameters. If you are looking for a simpler much more tollerant slipper clutch look for the TSS Clutch. It will not
work as smooth as the Sutter but is a lot more tolerant on outside parameters.

I ordered some washers for the six pressure plate screws from a supplier today so will try and fit them when I get the chance. What I keep on thinking about is why didn't they make the six screws 1mm shorter than they did if this is so crucial to the clutch mechanism working? Or maybe the six washers are just good engineering practice. Not sure why washers are sometimes used and sometimes not in construction of mechanical things. I always design things to have washers underneath bolt heads but, again, not sure why, I was brought up/trained/thought they were a good idea - they just seem like good practice because they allow the bolt head to turn to the right torque setting without damaging the surface underneath. But who knows?

Good one Fuel - you are making me more reassured that this is the problem. I've ordered six M5 stainless steel washers from Pro-bolt yesterday and I hope that they do the job. It's cheaper than ordering a stronger spring from Suter to see if this is the cure. I will try that next if I need to.

Cool - hope that works! Helluva lot cheaper than a replacement diaphragm spring.

I wrote toi Suter this morning on their website. Got a reply just now so thought that this was good service.
See below:

Hi David

Normally I should send you to the KTM dealer you bought the clutch from, but I understand that not all of them really know how a slipper clutch works.

What does your pressure and your back plate look like? Any wear on them?
Please measure the gap between the Bolt, position 13 and the release ring position 4, it should be aprox. 1.2 - 1.4mm.
Measure it like this, disassemble 1 of the 6 Bolt, and then measure the depth from the surface to the release ring, minus the bolt length.
If this is OK, no gambling is necessary with shims!

Please check and let me know.


Freundliche Grüsse / Kind regards

Roger Sutter
Masch. Ing. HTL
Production and Procurement
Suter Racing Technology AG
Mettlenstrasse 3
8488 Turbenthal
Tel: +41 (0)52 397 10 72
Fax: +41 (0)52 397 10 70
www.suterracing.ch
www.suterclutch.com

Delete post

The standard spring was very sweet. I loved the operation of that clutch, just not the lifespan.
IT was smooth and seemed pretty close to the stock pull, which IMO is pretty stout anyway.
The Yoyo was jerky and not nearly as smooth.
I ran the piss out of both clutches and the Yoyo still looked new when I sold it here.
The Suters....not so much.

Well, I'm hoping that I have found and cured the problem today but I still haven't tested the clutch yet. Tomorrow morning I hope to do this.

Took off the six M5 bolts and had a look at the ends. Really obvious that they have been rubbing against the ring as mentioned in the e mail from Suter to Jody. So I put six 1mm washers on them and reinstalled. Was going to measure all the plates but thought it easier just to see if this has done the trick. If it is I'm a bit perplexed because I've been running this clutch for two years or more with no problem 'till a month or so ago. Why it should suddenly start doing this is a mystery to me. But if the washers are the answer I might take them out again and turn down Imm off the ends of the bolts - seems a better way of doing things than adding in a washer.

Fook me, that aint clever is it?

Can you throw up the installation instructions for us to have a look at Bic? That may help as i have no idea what the Suter looks like?

Those bolts were likely a hairs width away from the ring, and the friction plates have worn just enough to allow contact. Once it starts to slip, i imagine it would get exponentially worse.

Tested clutch with the washers added underneath the six bolts today. It's a big improvement but STILL SLIPPING!!!!! Now I can only make it slip when I go straight to full throttle open between 6 and 7 thousand revs in 4/5/6th gears - this is quick and aggressive because I have the throttle cam fitted. If I roll on even slightly it won't slip and will red line without slipping but aggressive throttle it lets go.

So I strip the clutch again when I get home. The six bolts are STILL rubbing on the ring underneath the main spring - I can see where they have worn another new groove/polished line at a different angle from the first ones shown in the pictures. This is even with the 1mm washers. So I think I better measure the clutch pack to see if these are all in spec. They are all fine and as follows:

Total clutch pack is 50.77mm
Metal plates are all between 1.93 and 1.95mm
Friction plates are brand new and all 2.74mm

It's the total clutch pack that matters and it shouldn't fall below 50mm

I'm going to email back to my friend at Suter tomorrow and ask him what he advises. Me - I'm tempted to turn down about 2mm off the end of each bolt. Even from the cross section drawing you can see that there is quite a lot more bolt protruding beyond the bottom of the plate they screw into. It's obvious from looking at the the way the clutch works that if these bolts even come into contact at all with the ring that is attached to the basket then the main spring will not be able to push the plates together fully - no matter how strong the spring is. They would effectively stop the travel of the outer pressure plate.

I'm hypothesising that by adding the washer I've lessened the problem but need to be more radical. I don't really want to add two washers - doesn't seem like a good idea and the heads of the allen bolts will maybe start to touch the inside of the clutch cover.

Lets see what Suter says.

One other thing I've learned. DON'T try to take the clutch apart with a hot engine. The six M4 bolts are much tighter and almost impossible to undo. I've more or less ruined on allen head and mashed up two keys. When the engine was cold again it was much easier to undo the rest. I will get a torque setting from Suter. I'm going to fit new bolts when I reassemble.

Well I've measured everything again just to make sure I've got fact right. Clutch stack is good and the 6 bolts are exactly 19.5mm long. But they are obviously touching the ring still. so I'm going to order a load of new M5 bolts and turn them down to say 18mm and try that. Then if clutch still slips I'm going to go with SDNerd's wisdom and go for a stronger main spring. If that doesn't work then I'm stumped.

I just want to be able to get all that new found power/torque at the top end that my motor has got. Need the total package of full exhaust system, RC8 trumpets and quick-shifter working seamlessly to have the run up the start finish straight at Brands to fend off the inlne fours! It's funny really, riding smoothly about and sensibly on public roads you'd never know the clutch was slipping. It's only when you really, really ride hard and aggressive that it happens. But on a track it would be really obvious immediately and piss me off big time. Plus, I can't stand to know that something is not working perfectly - it bloody should do given the cost of it!

You have those is place : The washer is item no. 11 and 12 part number 60032035000 and 60032034000.
I haven't heard back if you checked those ...

Just got a reply from Suter...

Hi David
Bolts should definitely be replaced, all spare parts are available separately, please check attached drawing.
The bolts are not too long. Everything should be fine and working as you describe!
Clutch Plate package is fine with this thickness as well.
The only route of the problems I see could be the engine oil or the main spring.
Did you always use the recommended Motorcycle engine oil?
This is often the reason for slipping clutches!
Don’t think you are doing something good in using the fully synthetic, bloody expensive ones, just use what is recommended.
What is written on the main spring, 1310N? We could go to a 1500N one!
Please let me know.


It's all right him saying that everything should work fine but it obviously doesn't and the bolts are too long. I've ordered some new bolts - 16mm long, (not from Suter) and am going to try with these.

If the clutch still slips I will consider going up a strength of main spring but as already stated they are not cheap.

Klink....can you see from the drawing that the washer under the main nut is indeed the locking/tab washer that we both have. It's not a KTM part but a Suter one.

Did he give you a price for the washer m8? Are you ordering one? If so chuck me down for one as well.

Posted elsewhere, but here again for reference, my kit came with the 1310N diaphragm spring. I went to a 1400N.

I must admit I'm expecting my stack to come up short on numbers. If those clutch plates are still good after 44k miles -a fair few of those miles are in London where constantly slipping can be a fact of life - I'll be amazed.

Bic have your spare set on standby please

Klinky, I have my spare friction plates on standby if yours are knackered.

I've asked the Suter guy to came back again with a place to buy the parts from. I'm going to get a new washer or two and a set of the six M5 bolts. But in the meantime I have found this official Suter site with the main springs for sale at less price than previously posted. (78 Swiss Francs is about £51). Need to check the diameter of our spring - not sure which one it is - hope not the 86mm because the range for this is limited. This site doesn't list the washers and bolts as parts.
http://suterclutch.com/forge/shop.cgi?c ... ategory=73

I got a better reply from me Suter contact today which has clarified some major points and made me realise that I have been wrong about a fundamental thing regarding the slipper clutch mechanism.

On this thread there has been a lot of talk about the six M5 bolts that are maybe too long and hitting another component in the clutch causing it to slip. I've tried shimming them with 1mm washers to no avail - they still show signs of contact with the ring component, (Part number 4). If you look at the cross sections of the clutch you will see that the bolts have a clearance of about 1.5 mm with this ring when the clutch is operative in normal use.

What the guy at Suter confirmed today is that the bolts DO COME INTO CONTACT WITH THE RELEASE RING. THEY ARE MEANT TO. This is when the anti-hopping mechanism is activated by the reverse torque mechanism. That is why they show wear to the ends - not because they are too long but because that is how the slipper clutch works. This is normal and expected signs of wear and contact. (I'm really surprised that this is the way it's engineered but it is true).

So..... if anyone has added a 1mm washer to the bolt when it was not meant to be there they have effectively eliminated the ability of the clutch to deliver the slipper ability. If I had gone ahead and turned down these bolts in the belief that it would cure slip then I was wrong. I would have just ended up with a normal clutch that was not a slipper - and it would still have slipped under power.

THESE BOLTS HAVE NOTHING TO DO WITH THE CLUTCH SLIP I AM EXPERIENCING.

He has given me the part number for new bolts and a new stronger main spring. He says that this is all is can be. Everything else that I have sent him regarding the clutch plate dimensions and total pack width he has confirmed is within tolerance.

So in the final analysis it looks like SDNerd is the winner here - it's all down to spring strength. The additional BHP and torque of my engine must be just too much for the spring I have fitted.

He also confirmed that the torque setting for the bolts is 5nms.

I still can't believe that this precision clutch is engineered to work with one component interfacing at different revs with the ends of six bolts that are actually there to hold on the pressure plate. It just seems bad engineering to me. If the bolts are torqued down differently they will all be a different lengths and the pressure ring will be touching them unevenly around the six contact points. If you have any engineering mind and can read the cross section you will appreciate what I am saying.

The only reason I can see them designing the clutch this way is that the bolts are made from some extra special material that performs well in friction situations and that when they wear down too much you can replace them easily and cost effectively. The Suter guy says they should be replaced. They do call them Suter 'special' bolts in some texts so I can imaging that if you use normal steel bolts as replacements then they might wear out really fast.

Anyway, I bet no one is reading this thread anymore and if you are you are all bored of the subject!!

I just want a fooking working clutch like I used to have.

Thanks Bic...
In as much extra work you're going through..
It is definitely a learning experience..
How many times now have you
pulled it all back down now.>??? Once is enough..two times ok..
For me..any more and my brain hurts...lol
Thanks..!!! I've yet to get mine together..
But I have a much better understanding without having to suffer
what you have...
This post has a LOT of info to share...

Still not ordered through Suter because the invoice they sent through listed the wrong part numbers and there was no-one in their office on Friday to sort it out.

Out of interest I tried to find a UK distributor for Suter but the only one listed on their website is DRL Racing and they don't answer their phone and haven't rung back two days after leaving a message. Suter are really nice people, and make good products, but they are not set up to sell parts or deal with after sales service.

Tried another way too. Rang Jim Aim KTM and talked to a guy there. Asked if they sold Suter clutches but they don't - only Sigma ones. So I asked about the KTM Hardparts clutch and said that as far as I knew it was actually a Suter clutch with KTM branding on it. I sent through the drawings from Suter for them to compare to the microfishe files they have of the KTM hardparts clutch and they rang back to say that it was identical and that the parts are the same.

What is interesting is that the replacement main spring listed for a superduke is the same spring I have, (1235nm) but the same clutch for the RC8 is listed with a spring which is 1600nm. So they could easily order me the six bolts, the tab washer and the stronger spring. They are going to check on Monday what the price is and whether they have the option through KTM to order different spring strengths rather than limited to just those two. But anyway it might be quicker and easier than going through Suter.

Has anyone out there got an RC8 with a Hardparts slipper clutch? Or do they all come with one as standard? I want to know how hard the actuation on the lever is. I know that it's a different engine and everything and it doesn't mean that fitting this spring will feel the same on an SD but at least the clutch won't slip if it can cope with the RC8 power.

Bic,
It is exactly the same clutch just re-branded.
I covered this before I think.
Shame on a dealer for not knowing this. But what do you expect, right?
The thing I encountered was that Suter was under contract to not sell parts for the KTM clutch, rather you must buy from KTM.
I contacted KTM America, the headquarters, and they directed me to Suter as they couldn't get parts.
But Suter isn't allowed to sell parts.......circle jerk.
As much as I love KTM and would probably buy an RC8R if I bought another bike, the company itself is a classic example of having one's head up one's ass/arse.

As mentioned previously, contact with Suter is good, there's a guy called Roger Sutter and he knows his stuff and is really good at responding to e-mails. Problem is only with how they are set up to sell parts. His secretary has sent through a purchase order but it has wrong numbers on it and complex bank details of how they want paying with Swiss Francs. No credit card facility or Paypal etc. Don't even know how to make sure that the payment gets through at the right currency exchange rate.

If I can find a convenient way to order through a UK dealer then I will.

SDNerd. It's no good to me knowing how you get stuff in the States . I'm here in the UK mate. Anyway it sounds as though you're no better off than us anyway. I'm just trying all the options here. I've found a direct link with Suter but it's shit for purchasing stuff. Just want to find out a way that any future SD owners can short cut to the best way forward.

Anyway, why do you not think I'd be happy with the stronger spring - it's you that have been recommending that this it the answer to my slip!! Do you mean a 1600nm it's too strong? I'm trying to order a 1400nm - this is what I feel will be adequate.

I think I'm getting somewhere as well Bic. Mark @ KTM Centre has spoken to head of parts for KTM UK and he is on to KTM Austria for correct parts and numbers. Should know something early next week. Will let you know what happens.

have you changed / flushed the oil yet ?


i did say dont use them for service , just spares .

they overfilled a mates supermoto , and pressure washed his chain dry, left a filter loose and a load of other shit i cant remember.

I won't be using them again for any workshop work. Like you say just spares. They're just a load of salesmen there really, don't know about KTMs.

Decided to take the plunge yesterday and pay Suter direct into their Swiss bank account for the parts. They sent me a new invoice with the correct numbers on it and then it took me over an hour on the internet to do an international bank transfer. Had to keep paying additional fees for the transfer and also accept any that their bank asked for, (even though they didn't say how much it would be!!). And it might take up to 4 days before they actually get the fubds and send the parts. What a faff.

Just hope that everything goes smoothly and they don't get held up in customs with even more charges to pay.

Still waiting for Jim Aim to get back to me about whether they can get parts and then I can post up comparison prices.

Also Suter UK distributor guy did ring me back on Saturday from a racetrack - could hardy hear what he was saying.

that sounds like a faff to far for me dude , i would have given up by now and bought a different slipper.

Got all parts from Suter today, good service - very fast from payment to receipt of goods.

I'll fit them tomorrow and hope it solves everything.

Did my bits turn up Bic?

Craig,

Thought there might be something up with the amount they were invoicing me - something didn't seem right.

So the package has only got one spring in. Really sorry mate, not sure how this has happened. Only good bit was that you don't actually have a slipping clutch do you?

But they have sent two lock/tab washers as I asked for.

I can post it over to you if that's the best way or you can drop in to work again - let me know what's best.

At office today. It is here now. If you want to collect will be here till 5. If you dont show i can post - but pbobably not till tomorrow.

Up at 5 am to try and get this all fitted. Got nearly done and then all the three babies woke up and I get called back to family life. Christ this is no way to try and keep a motorbike going when you can't even fit a new clutch spring in one session. Will have to return to get the job done some other time this weekend. I hope.

My plan was to get up at 6 and get mine fitted and be on the road by 9. Instead I got pissed with Ronin in Camden Town. Staggered in at 2am but still woke up at 6.30 and have spent the last hour and a half trying to get back to sleep with a hangover. Given up now and plying myself with uber strong coffee and going to head out to the garage and get this job done.

Well I took it round the block to make sure it was all working ok. It's only a mile but has a steepish up and down hill. Didn't feel any slip on the way up but didnt give it any beans. Def felt the slip on he way down though. Little twist if the wrist and roll off and it slipped away. Slightly odd feeling at first, kinda like the tyre is sliding but in a controlled straight line. All very smooth. Have the medium slipping spring in there at the moment. Will ride it in anger tomorrow.

Got round to re-installing mine finally. This is the new 1500nm spring fitted.

This is the slipper ring that moves out when there's reverse torque applied through the clutch. This edge pushes against the bottoms of the six M5 bolts and releases the pressure holding the pack together.

Will test ride tomorrow. please, please, please be fixed with no slip under power.

The middle spring feels much lighter than the standard clutch springs at the clutch lever.

Ok mine is doing the same as Bic's Thought I'd just pop up the A1 and open her up before tucking her up for the night. Aggressive roll on from 4k in 4th, 5th and 6th result in slip around 7k onwards. Even slips a bit with aggressive throttle openings in 3rd. fooking annoying as I have a trackday at Cadwell on Thursday and swapping the whole lot back is going to be a pain in the arse. I feel your pain Bic I really do The spring they supply just can't cope with the torque it seems. It does feel a lot lighter than the standard KTM clutch spring.

Thats reet shit that it does not work correctly, will stick with the sigma when i eventually get another.

Mate, that's a bummer. So wish that they had sent two 1500nm springs as I asked. Well, let's not be too hasty though because I still haven't tested this to see if it's cured the problem. If it has though I have the details and the direct contact with surer. Only took three days to get parts once I sorted out how to pay them.

I think that the standard clutch with the 1230nm spring is just not up to the SD when you liberate the extra power. Interesting that our bikes are the same really, Motobox, full akras, etc.

Fingers crossed Bic, bloody hope it works!

After reading all this Klinky I think your best bet is to punt it and buy a sigma.

You'll get good money for it and for a little bit more you can have a brand new sigma.

Miles less hassle than all this carry on man and a lot easier to fine tune by just changing a £3 steel plate. Takes 5min.

Well I swapped it all back again. Only took 50 mins so not too bad.

The only thing I did notice was that 2 of the steels were put in with the sharp edge from being punched out facing outside where as all the others had the sharp edge in. Can't imagine that was making it slip though. Measured the pack again and it was only 49.89mm so I need new friction plates and steels. Going to order those and the heavier spring this week. Bit gutted it didn't work though. I think I might also put the heaviest slipper spring in as well. Don't think I require that much slip tbh.

It uses GSXR springs but you get them easily. Mine came with them.

The GSXR plates are the same as the sd ones apart from you can get the steels in 2.0 2.3 2.6

All you do is measure the clutch pack and add whatever size you need. The standard ktm is 2.3 so if all our std pack is in decent nick you can just throw it all together and it'll be cool.

I wanted a little bit more slip as it was still moving a lot on the downshifts under braking so dropped to the 2.0 and it's cool.

You can fine tune it further by swapping some of the springs to the std lighter ones if you needed.

It's all on the Sigma site under the race setup section.

THE NEW NEWS IS........

Slip under power is totally gone. Just been out and done a proper test round the countryside and M23 and can't get any other feeling than total power through to the back wheel.

So basically a 1500nm main spring will cope with up to 125 or so HP. It doesn't feel any harder to operate than the old set up to be honest.

The only down side at present is that there is quite a lot of drag, hard to get into neutral and wants to creep forward in first even with the clutch level all the way in. Is this normal when fitting a new set of friction plates? Obviously the clutch pack is slightly wider than the old one and so the same travel when you pull the lever in will not separate the plates as much but I wouldn't it expect to drag like this. Do they need to bed in a bit like brake pads ? The clutch engages very soon as you let out the lever - had to adjust it with the lever span adjust but it's not quite the same thing is it. Maybe I'll bleed the clutch hydraulics because I haven't done this for a while.

Good news that the slip is gone m8. Thank fook for that!

Can you email me the contact details and part numbers I need please Bic and I'll get on the case tomorrow.

If you can wait for tomorrow morning I can forward you the e mail from Roger Sutter and the lady who sends out the invoices. She can send you the purchase invoice with payment details, then she dispatches them once they have received funds. It took about three days from paying them to getting the bits. It's a shit that they didn't send two springs in the first place, I did ask for two of everything except the six bolts. Must have been a misunderstanding somewhere. I checked the invoice though and they did only charge me for one.

I am getting a bit confused here still.
Doesn't the choice of spring tension, 1500nm, 1300mn, etc. only effect the pressure of the clutch on deceleration?
The point of the slipper is not to change how the clutch is engaged but how it disengages on deceleration.

I will tell you straight away that the Suter/KTM clutch has infinitely a better feeling clutch than my Yoyo.

That's the way I understood it too. That is why I was wondering about all this talk of heavier springs.
The STD spring worked fine for me but now I wonder if its lack of force causes the pressure plate to wear out prematurely?

I used the middle on, 1310 or something like that right.
If you look at my old link from earlier in the thread you will see I did in fact go through a pressure plate, BIG TIME! Funny thing was I never really noticed it was sipping until it was slipping to almost failure at corner exits, hard on the throttle.
I sold it and a couple of other of my Suters on the forum and I think most of the guys got the new/replacement parts.
I am pretty sure Omky did anyway.
Like I said, I LOVED that clutch!
In hind sight, I would have paid full price for another instead of the Yoyo. That Yoyo was grabby and not exactly smooth.
The slip function was fine but normal use was a bear compared to the Suter/KTM. I went from great launches with the Suter to a grid stall and porpoise wheelies at another grid with the Yoyo.
In that video at Fontana in Jan 2011 you can see the clutch grabbing when I pull out of the garage.
It is what I notice and remember every time I watch it.

The clutch plates were soaked with oil because they had been fitted and used before the new main spring was tested. The clutch dragged when the engine was cold and then didn't really improve even when fully warmed up and 50 miles of hard testing.

Latest story update is interesting. This thread will run and run I think! Sent Klink the details fer Suter for him to get a new main spring but this morning I get another missed phone call from a Guy called Dave at Suter UK distributors - I keep on missing his calls. He says that he's going to Switzerland tomorrow so could get any parts I need and save me the tax and postage. Too late for me but I ring Klink and give him the number to ring and sort himself out.

He's rung me to say that he's talked to Dave and that all the KTM/Suter slipper clutch parts are actually just standard Suter parts and that he probably has everything that any of us want off-the -shelf in the UK.

So... the moral of the story is that there IS a place to get Suter parts in the UK and that there IS someone who knows about these clutches. I'm going to ring him tomorrow to ask about my clutch drag and see what he recommends. Looks like Klinky gets to order the main spring at a fraction of the cost I ended up paying for it! But that's the way of the world I guess.

You are a bit unlucky there Bic. Cheers for sorting me out though m8

Here are Davids details off Suter site. He said he's actually semi retired and sold the garage but the mobile highlighted still works for sure and he does still import and supply Suter stuff. Always happy to chat and offer any advice about them as well

DRL Racing
28b West Street
Oundle
PE8 4EF Northants
Tel: +44 1832 273 738
24hr Race Support 07590 832058
Fax: +44 8444 127 324
[email protected]

OMKY, after fitting the 1500nm main spring the clutch didn't slip.

I tested it as much as I could in the few hours I had and couldn't detect any slip under any conditions. After having had a slipping clutch for as long as I have you get very experienced with when it happens and can really hear/feel when it begins to slip. And it doesn't now.

Haven't had a chance to bleed the clutch, need to get some mineral oil, then I'll do it at the weekend. If the drag persists I might swap back to my old set of friction plates just to see if a slightly narrower pack changes anything, (and to see if the slip is cured with the stronger spring).

Not sure what strength Klinky just ordered from Suter, maybe the 1500nm too but if he went for a 1400nm be interesting to see if that works for him.

I really cannot believe this thread..........

I have had two bikes with Sigma slippers and they were no trouble at all

Fitted mine again today with the 1500nm spring and hey presto no slipping on power. Looking forward to testing on a blast out with Mr and Mrs Millar in the morning

Speaks too soon, it gave up the ghost at Snetteton halfway through the open pit lane

New friction plated finally arrived, can anyone tell me the pack thickness of just the 11 friction plates? Also I measured all the steels and 9 of them are between 1.84 -1.88 but 1 of them is 2.14mm thick. This is also the worst marked of the lot. Any ideas why just one is this thick? Was it supposed to be in a particular place in the pack?

Also after a quick go on Ronin's SD I'm going to try the heaviest slipper spring. His Sigma doesn't slip anywhere near as much as mine. Anyone tried the heaviest spring?

With so many issues going on with these slippers..
Doesn't Suter have an directions sheet of exactly
"How to"
Or
Has anyone put one together.???
I'm thinking it is or should be very straight forward
with exactly where each plate goes and what to look
for..
I'm still waiting to purchase the rest to make my Suter
Slipper and install it..What a lot of pain and suffering

I got the KTM Instruction booklet with mine and had no problems fitting it.

I am curious as I bought the EBC friction plate pack. The combined thickness of the 11 plates is 31.16. My old pack is down to 29.88.

This thicker steel is slightly confusing then. There is no mention of it in the instructions for the Sutter or KTM Workshop manual. It looks like the other 9 steels in every way. It's only when I measured each steel that I noticed the different thickness. As I said it's also the steel that has the worst scoring marks on it.

I installed Ronin's SDR pack so I could ride in Scotland at the weekend. His combined pack thickness was 50.13. I will whip out his pack in the next couple of days and see if he has a thicker steel in there.

The reason I ask about the heavier slipper spring is that mine slips on shutting of the throttle at anything over mild acceleration and not just change downs. After briefly riding Ronin's SD it doesn't appear to slip in the same way. I am more worried that this is wearing the steels and friction plates. Does the slip mechanism wear these???

This is what you need

Contact Neil Spalding or your local Sigma Performance stockist for further information.
Phone 0788 1820 748 (Mob)
Fax 01892 548996,
Email [email protected]
Sigma Performance Limited
Beadles Yard
Lower Green Road
Rusthall
Tunbridge Wells
Kent
TN3 0NA

Just ordered 10 steels from Gear4. Mine are right on wear limit so that def not helping. They couldn't answer why one of the steels was so thick. They are meant to be 2mm when new.

At least you guys are getting to ride your clutches. Me....... I'm in the middle of house moving, holidays and DIY from hell. Up to my armpits in sewage and blocked drains yesterday, today it's sanding and painting skirting boards with a carpet fitter arriving in two days. Crisis management or what!

My clutch seems sorted now but not like I can get out and try it. Bought some GB engine covers from a member onhere because - to tell the truth, the biggest pain with me sorting this clutch was that my carbon covers are siliconed into place so every time I need to wap off the cover I need to prise them off, clean them up and then silicone them back on. Ever the optimist I do it every time only to have to get them off again. The GB bolt on covers will be a godsend!!!

BTW - isn't Snetterton that loop that looks like a penis? Do motos roll on the outer loop only, or do you do the infield part around the pond also? That layout looks kinda interesting - does that inner loop even exist yet?

Snetteton 300



Yeah this is the track all the bikes use now. Its good fun and flows quite well, bloody fast in some bits. I'm struggling with a couple of the right hairpins but I always struggle with right hairpins

I know it's been a while guys but who has personally had luck with Hinson for replacement parts in the US. I just called them and they had no idea what I was talking about....Trying to order a 1500nM spring.Thanks

Thanks for the info. I've been reading through the many threads on the issues and fixes for the Suter clutches. That's why I was so surprised that the girl who picked up the phone at Hinson had no clue what I was talking about. I didn't get a name, but she put me on hold to ask around if anyone had info. I think she was just confused because they obviously don't show Hinson applications for the 990, even though I thought I explained myself pretty well... I'll give them a call and see if I can get further with your contacts. I'll also try the 1400nM as per your suggestion since the bike will see the same intended use. I knew some people had tried it but never found a thread with results vs the 1500nM. I'll keep you posted. Thanks again!

I think I talked to the same girl as Kronos... she wasn't able to help me. I just talked to Chris and he's gonna get back to me since I didn't know the o.d. and i.d. to give him so he could make sure he had the right part. Said he's gonna check and give me a call tomorrow. Hopefully all goes smoothly