Foreign body.

Hi all,

so a few weeks ago I finally got my dealer to open up the engine and replace the base gasket in the front cylinder which had been leaking for ages. I really wanted it done asap cos it had got so bad and it was too cold/wet/snowy to work it myself. They did a decent job, sealed her up tight and went a few extra miles to sort out some other little bits to make it run sweet which I really appreciated.

I ride it home (50 miles) and enjoy it. I ride it again on a little blast when the weather breaks (another 50 miles) and enjoy it, but I'm not pushing hard cos it's too cold.

I get it home and notice another oil leak. No biggie though it's only coming from the gear position sensor so I order a replacement seal (pence) and get to work on it last weekend to replace it. I drop the oil in case it's all gonna piss out when I remove the sensor (as per dealers advice). Once oil has stopped dripping from the sump drain plug I notice something hangin out....so I pull it out. 2 pieces of metal! NOT swarth though!! SO I clean it up and proceed to ID the buggers. I am convinced it's what's called a 'safety clip' that goes in the front cylinder and secures the piston head to the rod (rough explanation), you can see it on the drawings for the engine parts.


Here are some pictures:







You can see from the last image that it's been through something that has marked in and twisted it but clearly it only went through once as there's only one set of marks on it.

I called the dealer and sent him these pics, we have chatted at great lenght about it and he assured me it couldnt be from my bike cos if iti was it would have lunched itself very quickly and that I can ride it but must pay attention to the noise/vibes for a few hundred miles. I aksed him to put all that in wiritng to make sure I was covered in any event and he said yes. Before he has done this I get another call today telling me they are going to come and collect my bike and open it up and check it out fully and then deliver it back to me. He says it would have been unprofessoinal to not do this and that I've been a good customer there for years.

So, they are coming this weekend to collect it.

What do you think?

It doesn't look like the piston clip to me. It's too large, and it's shaped a bit wrongly. Also it would have been nice to have some sort of scale, other than your fingers. So, I might be wrong on the size.

The reason why I say that it looks unlikely to be that is because of this:


This is the piston from my Yamaha DT125LC. The piston clip came out of its groove and this is the damage. As you can see, it's total annihilation. EVERYWHERE. Your bits are waaaay to clean and they're not even squeezed and flattened in a way that would suggest they go between the piston and cylinder wall. I mean, you can see bits lodged into the piston in my picture.
The bike basically ground to a halt for a microsecond when the clip flew, but then the bike kept running, it only achieved about 2/3 of its top speed with the piston fooked like that.
One easy way to test this is to simply test the compression in both cylinders. If one cylinder is screwed, then the one cylinder should show a lot less compression.

I'd start looking for some other locking clip somewhere. Good luck!!

Rest assured I'll be demanding photos of the engine to prove it's not shagged!

Shade, yes, I clicked... I don't have the ghetto model, I have the royal R-model, so my manual is much cooler, all the numbers are +100, because it's BETTTAR!!111

Had a peek throug the manual, there's tons of those little clips everywhere.
I was surprised to see that there piston pin clips have a thing bent outwards, not inwards. All clips I've seen have either one or two things bent inwards, not outwards. Which gives the piston pin clip theory a bit more viability.

Kinda like this:

However, when I just searched for the pic, most pics show the piston pin clips without any "ears"...

Can anyone say "Overbore" and "flowed head"...?

The SD piston is not like the 2 stroke piston pictured,,it has a very short skirt and is cut away around each side were the gudgeon pin fits.
So i could see the pin falling out and not contacting the piston just dropping down. Of course the big worry would be the gudgeon pin moving then , i hope the dealer finds the problem and tells you honestly what it is.

From the pictures my I could have quessed that the clip fits onto the pin (clip squeezing inwards), and not into a groove (clip pushing outwards) as "traditionally".

Then the clip could have, as you say, fallen down.

This site has some good pictures and in one of them you can see the clip - definitely looks like the bits you found.



My guess one of the following >

1. The mechanic dropped it but used another one - only the mechanic would know this.
2. The mechanic dropped it but didn't use another one but 'buttoned' up the engine anyway - only the mechanic would know this.
3. The mechanic didn't install properly and it pinged out.

My guess if the engine sounds OK now then it probably will be fine once they've refitted a new clip.
Just means shed loads of work to strip down again plus parts (new gaskets, oil etc)

Big f**k up and you've every right to be pissed off with them, but I guess these things can happen.

ps I would also want to see that the bores / piston are OK.

Id just be worried that they may not find the rest of the clip, unless it's disintergrated.

Orpheus is spot on.
Having seen this pic;


Spot the clip there at the bottom left in the pic...

I sincerely hope that a monkey dropped the clip into the engine and it's done no or minimal damage. If it's come off the pin when the engine was running I'd expect more damage, unless it's magically dropped itself only downwards.

I find it strange that these clips are even used today. They've caused so many engine failures over the globe over the year. I know you can get teflon "plugs" that you use instead, but you need a "hole" to stick them in. Doesn't look like the KTM piston is designed that way.

*fingers-crossed*

ghetto model? Must have gotten cranky from riding an uncomfortable bike. lol

Chalk one up to the magnetic drain plug for grabbing that junk.