Author Topic: uh oh??? frame might be bent???  (Read 856 times)

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Offline domer

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uh oh??? frame might be bent???
« on: May 28, 2011, 09:17:22 PM »
it looks a little bent to me, if it indeed is... its been like that for a while. my triple tree is shot too. steering stem is bent pretty bad. im getting the feeling this iswhy icouldnt take my hands off the bars.... but i kinda thought it was misaligned fork tubes. anyone got a lower tree for a 500 laying around?

Kinda looks bent right in front of the valve cover, too me at least... should i be worried?
 




Offline Hannibal Smith

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Re: uh oh??? frame might be bent???
« Reply #1 on: May 28, 2011, 09:45:59 PM »
Looks bent to me also. Tough call as the frame has the VIN, as your best bet is another frame IMO.
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Offline 754

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Re: uh oh??? frame might be bent???
« Reply #2 on: May 28, 2011, 10:04:33 PM »
 If it is it looks slight..
 Check your forktubes first, then trees.
 I got a set for a 550 if you cant find down there.. but I can easily tell you how to straighten the lower one.
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Offline Greggo

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Re: uh oh??? frame might be bent???
« Reply #3 on: May 28, 2011, 10:15:34 PM »
Damn, I hope it's not too bad.

Offline domer

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Re: uh oh??? frame might be bent???
« Reply #4 on: May 28, 2011, 10:33:31 PM »
Well I'm pretty sure it's old damage I never caught, and I've put about 6k miles on it. Could never let go of the bars though, it would dive if I did... But it would hold steady at 90-95, just don't let go. the steering tube is also trash, also most likely old damage. I don't recall pulling the whole triple apart before. So I'm guessing it's old damage too... The bike had been in a pretty bad head on collision before I got it... I think I'll try a new lower tree and see how it goes. I'd hate to go through a frame swap DMV wise.

Offline dave500

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Re: uh oh??? frame might be bent???
« Reply #5 on: May 28, 2011, 11:10:35 PM »
with the front end on,,and you looking at it all squared up,,the front wheel centre line should marry up with the oil filter bolt,,if it obviously is not shes twisted aswell,,damn bugger if it is,,you can get them straightened,i can let go with both hands at any speed,the flat area around the forward tank mount,,is it indented at all?or all nice and flat?

Offline HondaMan

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Re: uh oh??? frame might be bent???
« Reply #6 on: May 29, 2011, 09:26:31 AM »
Usually a bend like that is not fatal to the frame: I have straightened several that were worse than that with a bottle jack and a piece of pipe as an extension. The ones I have seen were bent by either someone backing over the bike with a car/truck or the rider hitting something like a curb or someone's bumper.

Fixing it does require engine and wheel removal, so it is a total teardown to get there, usually. Then you brace the jack off the back side of the frame from the bend, place an appropriate length of pipe on top of the little bottle jack, and gently but firmly pump it a little beyond the impact direction so it will spring back to straight when 'let go'. You must either keep an eye on the frame tube at the jacking sites (so it doesn't crush), or make a small 'saddle' to spread the load around, like a piece of 2x4 wood with a hole drilled on one side to accept the pipe and a groove or V-notch on the frame side so it will stay in place while you jack. To check for straightness, you just have to reinstall the wheels and forks and check to see how in line they are.

One thing this method WON'T fix is side impacts to the frame. That usually turns the bike into a "C" shape.

It's actually not as hard or tricky as it sounds, and before we had too many lawyers it was a good way to save a bike frame. It is STILL a good method, even found in old textbooks on the topic, but having too many [and underemployed] lawyers today has ruined that practice by shops and folks like me (except for my own bikes).  ;D
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