Bike repair

dee jones · 01-30-2006, 11:31 AM

The question is for you guys in the know is, My S has been acting strange since I laid it down. It didn't go down hard ,but I guess hard enough. The fork stops broken on the left side, and the tabs were broken on the frame under the seat. When the bike is laid over to the right it pushes back to the left. If you guys were going to be replacing the neccessary parts, where would you start? I wanted to try this myself before I take the bike to Compy Track. Any help appreciated. Do any of you guys know how to instruct me in taking measurement from lines laid down on the floor?

Steve Carlton · 01-30-2006, 11:37 AM

Do you have comp/collision insurance? If so, I'll bet the bike could be a total loss.

The frame tabs under the seat can probably be successfully welded by someone who knows what they're doing. You could also look into getting the tab replacements used on the Boxercup bikes, but that's probably a lot more hassle.

dee jones · 01-30-2006, 11:47 AM

The bike was a total loss and I bought it back from the insurance company, I 've all ready started on it . The frame tabs have been welded and seem to hold. Put new wilber shocks on and repaired the broken fork stop. One of the Bmw Ducati mechanics rode the bike, but wasn't sure where the problem was. The bike can be fixeds I've put about 900 Plus miles on it . The handling is just scarey.

AndrewA · 01-30-2006, 01:46 PM

Dee - Have you checked the fork tubes?

Loosen the triple clamps (one side at a time). Twist the fork tube by hand- it should spin freely with no run-out (wobble) or binding. If the tube is bent, you should be able to see and feel it.

Does the tube bind on compression ? (Put the bike on the center stand, and bounce up and down a couple of times).

Flatbutt1 · 01-30-2006, 04:00 PM

Quote:

Originally posted by dee jones
The handling is just scarey.

A tweaked rear sub frame? What could cause the rear to not track true behind the front?

bikpaintr · 01-30-2006, 05:23 PM

I'd agree on the tweaked sub frame, if it went down hard enough to break the tabs it's probably bent. Also take a real good look at all the front end components as something up there could be bent as well. Checking the frt/rear wheel alignment would be a good place to start.

AndrewA · 01-30-2006, 05:30 PM

Quote:

Originally posted by Flatbutt1
A tweaked rear sub frame? What could cause the rear to not track true behind the front?

A bent rear sub-frame shouldnt effect turn-in.

Your ass might feel somewhat rummy (I have a feeling some of you know what ......), but handling should still be nuetral, no matter how tweeked the rear sub-frame might be.

I'm not sure what allignment can be done on the S (as far as alligning the front wheel with the rear via a piece of string), as the rear is non-adjustable.

dee jones · 01-30-2006, 06:12 PM

Thanks guys I'll start with the fork tubes and stearing head.

gigantic · gigantic's Garage

when i crashed last summer i rode for a few weeks, not realizing why i was so terrified of going over 100 mph. braking was particularly scary. went to the track-side Computrack Vendor. sure enough, bent forks.
get-em checked out.
Lance

dee jones · 01-31-2006, 05:19 AM

I'll check them ASAP. thanks. 100, thats breaking the law?

gigantic · gigantic's Garage

closer to 130-140, actually.
it's not breaking the law if it's not on a public road...
L

dee jones · 02-03-2006, 02:17 PM

The front axle seems to go in and out okay ,and the fork tubes seem to spin faily well when the triple clamp is losened. I'am trying to decide where to go next. I'am hoping its something simple because theres really not much damage. I guess the likely culprit is the steering yoke where the fork stops broken. You guys got any suggestions?

AndrewA · 02-03-2006, 02:34 PM

Can you please explain the symtoms again?

dee jones · 02-03-2006, 02:55 PM

When the bike is laid over in a right hand curve it seems to push back up, also in a straight line when hands are removed from bars it pulls to the right. Makes no sense that it tracks right and pushes up or towards the left.

wswartzwel · 06:03 PM

You're in Charlotte NC. sounds like the perfect setup for NASCAR....

dee jones · 02-03-2006, 03:14 PM

Got a NASCAR and Ducati mechanic trying to help actually. But they know little about Bavarian Murder Weapons, which is what my SBX has become.

JonyRR · 02-03-2006, 03:21 PM

one thing to check; the symptoms of this will fool you and it might just be sheer co-incidence.
check the paralever pivot bearings; loose pivot bearings make these things handle wierd and they DO get loose/worn/gorfed...

wswartzwel · 03:27 PM

gorfed?

Edit: nevermind found it in the urban dictionary...
1. gorfed link send redefine 9 up, 6 down

-to be physically or mentally distorted, an advanced form of being retarted.Justin Lake was born gorfed

onekiwi · 02-03-2006, 03:35 PM

sub frame has nothing to do with wheels best to check bottom triple clamp, these thing get a twist on after a down
check to see if the steering lock works freely
have a real good look at the A arm / fork bridge
for any paint cracking or dents
as even a minor kink can throw the front wheel out
you may have to pull the forks out to check things

carl

AndrewA · 02-03-2006, 04:23 PM

I'd still wager its fork related. As onekiwi said, maybe one of the triples is twisted, or even the bars.

Maybe it's time for a wheel alignment?

http://motorcyclistonline.com/howto/stringalign0402/

Also, level the vertical plain of the wheels, and make certain that the top triple/bars are centered.