Rear-end on freeway, bent swing-arm?

So riding to work today i was rear-ended on the freeway and although i suffered no injuries, there was some damage to the bike. Less than you would imagine but he hit me pretty hard. It seems my tyre took the brunt of the hit as there is a huge chunk missing out of the middle. Upon closer inspection it seems that the tyre might be the least of my worries. It looks like the chain is much too close to the tyre and the rear sprocket is much too close to the swing arm. Take a look.




What do you guys think? Is there any prominent areas that i should be checking for damage that might otherwise go unnoticed? Ill give a better account of the accident when i get home.

Check with a straight edge like when you do a wheel allignment and if in any doubt get it checked by a professional!
Play special attention to where the frame mounts to swing arm and engine mounts.
The SD frame does bend and due to the construction it is sometimes hard to pick up with the naked eye.

Its either frame or swinging arm or wheel its self or all three ....you need to get it checked ASAP...

hi tigerstyletroy
the pics look normal to look at the sprocket does only have around 3mm clearance.. the rear tyre has about 5mm . if you have fitted another tyre still the same size ,they do vary a little make to make ,even though its same size 180. just noticed you have a dunlop fitted .. i have used super motos with chain just touching tyre .
you will know when you ride the bike if there is a problem , i would get it checked as a safety measure .hopefully you get the right person to check ....
things to check.
1 .underneath swing arm by rear axle, front where it goes across frame mounts . both sides for ripples ,sides top and bottom be very small , depends how fast impact or moving or stopped .
2. get back of bike in air ,check for side movement. should be none. check up and down movement when back on floor,should feel normal .any noises or grating could be a issue
3.as others said check with straight edge and check axle.
4. probably the most important thing is stress fractures on the swing arm ,suspect areas will be the axle mounting and front swing arm mount ,check the welds ,the swing arms are very thin ..
how fast was the impact? were you stopped ?did you have the front brake on , was the bike dropped ?. these things will make a difference to damage .

okay let me give a more detailed account of the accident. Doing probably around 75mph on the freeway and i look in my mirrors to see a giant 4d infinity sedan hurtling towards me. In that second i both i sh*t my pants and braced for impact. Literally no time to react...anyways he hit me so perfectly square that my rear wheel got lodged into his front grill, holding the bike upright and pushing me along at 70mph and slowing.

As we slowed down i bailed off the bike at around 10 to 15 mph and as he stopped the bike jarred loose and flopped over on its side, sliding for a short distance maybe 5 feet at most. During the entire incident not once did i touch the brakes, i merely steered the bike and held on for dear life trying not to end up on the ground in the middle of the 101 during the morning rush. Little cosmetic dmg, clutch lever ground down a tiny bit, shift lever a bit bent and ground as well as the rest of the shift linkage.

Bike was running fine and i was able to ride her home very carefully with my friends following on their bikes. My friends seem to think that while riding, the rear tyre seemed cocked to one side. The screw for adjusting the wheel shown in the first picture has about 5-6 threads showing while the other side has only 4. Although the chain clearance, as you said Rac, is quite small, i can see areas where the white lube from the chain has rubbed onto the tyre. Btw...its pretty funny that the forum automatically changes the spelling of tyre when posting.

Edited for easier reading.

I would remove rear wheel and check everything over, then put it back together.

Measure both sides of the spindle from the swing arm pivot to make sure it's straight.

My thinking is that it's more likely that something is misaligned or a minor part is bent rather than the swing arm.

hi tigerstyletroy
oh mate lucky to be alive after reading that ... the chain adjusters on the back are not that accurate in all fairness. the impact of rolling mass would be a little easier for the bike rather than a dead stop bang up the rear .
i would still have a good look at it all over.

Hope you got the cage drivers info. In my state, (Oregon) you are responsible for the vechicle in front of you. Failure to maintain proper distance or some sort of wording. I would be sending the bike out for complete alignmet check, and then be looking for the cage driver to send in the payment check. As said, the frames will bend, I replaced mine.

Well as soon as i was able to talk to the guy, the police had arrived and refused to let me talk to the driver of the car. He was afraid there would be a physical confrontation i suppose. Anyways in order for me to get his info i had to wait for the police report to be completed. Then i had to find the CHP office deep in LA... What a hassle. Anyways i talked to his insurance and gave them my account of the story so now they are just waiting to hear from their client.

From my side of the story it seems obvious that he was at fault, however i feel his side of the story will paint me as the one responsible. Im worried they might just take his side?

Unless you cut the guy off, any rear end accident in California is always considered the fault of the person behind, as in, the goofball that ran into you. Sorry to hear about it and I'd follow everyone else's advice and get it checked out for sure. Make sure and get yourself checked out as well. Physical problems don't always manifest themselves immediately following the crash. Good luck.

I am just happily amazing you didn't crash and have bad things happen to you. Whenever I am on the highways out here in LA I am a bit nervous some idiot will do something. Glad you are ok.

Well the mechanic i took the bike to gave me good news, the swing arm and frame are fine so its just the tyre and cosmetic damage. The only bummer is that somehow the california highway patrol found me at fault for the accident and his insurance is going to take the word of the officer as golden. Is there a way to fight this in court? I had a witness but because he was a friend of mine the insurance company refused to take his statement saying he would be biased. Maybe its not worth it in the long run and i should just pay for his car. What do you guys think? Keep in mind im only 21, i work full time and attend school full time so i dont exactly have the resources for a lengthy court battle.

How did the officer find you at fault? Like other s have said, unless you pulled out on him the person behind is always at fault if rear ending the vehicle in front.

How did the accident happen?

As Klinck rightly states in this country if you rear end someone its your fault because you should have the correct braking distance to the vehicle infront (as it should be in all countries).

UNLESS you pulled in front of him and the accident happened immediately after 50/50 IMO.

Cant comment further until you give a detailed account of what happened, I dont know how they can say your friend is not a witness, he is still a witness.