Bike starts to "wobble" at higher speeds?

[bonanzadave]

Jim,

Does the same thing with or without air. No fork brace. Rear Progressives have HD springs. Everything set on 2. Top fork preload, bottom dampening knobs, Rear spring height. Forks moved very smoothly by hand when mounted without the springs installed.

Same wobble today after the upgrades as it was 5 years ago.

Looking back I was not able to get the lwr race out of the 3-tree so I put the All Balls bearing on the old race. It seemed very smooth.


:-k

 

[posplayr]

Jim,

Does the same thing with or without air. No fork brace. Rear Progressives have HD springs. Everything set on 2. Top fork preload, bottom dampening knobs, Rear spring height. Forks moved very smoothly by hand when mounted without the springs installed.

Same wobble today after the upgrades as it was 5 years ago.

Looking back I was not able to get the lwr race out of the 3-tree so I put the All Balls bearing on the old race. It seemed very smooth.


:-k

Dave,
You need some idea of what your sag numbers are. By measuring the:
a.) free length (totaly unweighted)
b.) static (without rider)
c.) loaded with rider

This gives you two data point, compression under bike weight and compression under rider plus bike

you are able to determine if
a.) the spring rate is sufficent
b.) preload is set for ride quality

Also putting a tie strap on the front forks helps to know how much travel you are using. Usually braking causes the biggest compression, normally you should not exceed more than about 2/3 of total travel on a relative smooth road (that is what I have found). If you do then a big bump will bottom out.

Did you set the head steering bearing friction? It should be firm but not notchy.

 

[Sandy]

I've been reading this thread and everything that could be a problem seems to be covered. This is a little off the wall but try loosening and retorqueing the engine mounting bolts. The engine does provide stiffness to frame and over the years can either work a little loose or even move in the mounting holes while still appearing to be tight. Loosen them all at once and retorque, not one at a time. It should only take a couple of minutes to try, might help, might not. The reason I say this is because when I had my Yamaha 750 triple I had to do this about every 15,000 miles to eliminate some engine vibration. The mechanic said that the engine can actually creep in the mounting holes and in this case caused some extra vibration in the bars. Procedure was to centrestand the bike, put some blocks under the engine so the front wheel was off the ground, loosen all the main mounting points at the frame (not the plates, although it wouldn't hurt to check those also) so the engine would now be at the top of any slack in the holes and retorque. This stopped the vibration for quite a while and over time the engine would actually migrate to the bottom of the holes. Only took a few minutes to fix. Maybe over time these move a bit causing either a slight misalignment in the frame or not providing a rigid enough mechanical bond to stop frame flex. Or maybe a misalignment from the bike being dropped. I haven't heard of this causing handling problems before but it's easy to check and who knows with these old bikes what new problems can crop up that we haven't heard of before.

 

[bill_khaos]

wobble

wobble

hey........seems that all has been covered... i had a simular problem on a fzr 1000.... at 150 it started shaking like the middle had a hing. you could control wobble with speed.... after having dealer go over everthing the the yamaha rep fixed the problem,,,, never would have thought it... it was the tires ... the way air went over and around the tires is what made it wobble,,, i put oem brand tires back on and wobble went away... just a idea????

 

[bonanzadave]

Sandy, Thanks for the input. My brother tipped it over in the driveway by bumping it with his truck. The wobble started not long after. Hard to remember it was 20 years ago. I thought I had a wrench on every bolt on the thing but just a couple days ago I found the Fork support horseshoe bolts loose. Im gonna check em all again.


Bill, The tires are brand new. Avon Road Riders. Lots of guys have em on 1100Es. Funny though....no one has yet to say they have no problem going wide open in 5th. Except maybe the drag racers. Has any body taken an 1100E with Road Riders up to 7Krpm in 5th ? I cant get to 6K ?

Edit: Well crap ! The back tire has only 20 psi. Stand by Ill be right back.....I hope.

 

[posplayr]

Sandy, Thanks for the input. My brother tipped it over in the driveway by bumping it with his truck. The wobble started not long after. Hard to remember it was 20 years ago. I thought I had a wrench on every bolt on the thing but just a couple days ago I found the Fork support horseshoe bolts loose. Im gonna check em all again.
?

Hmm................

Bill, The tires are brand new. Avon Road Riders. Lots of guys have em on 1100Es. Funny though....no one has yet to say they have no problem going wide open in 5th. Except maybe the drag racers. Has any body taken an 1100E with Road Riders up to 7Krpm in 5th ? I cant get to 6K ?

I think Bill takes his L up there easily with his 1230

 

[sk843143]

something not said was road condition...... i know in michigan they put tracks in the concrete going with the direction insted of acrost it ...... when ever i hit that part of the road the bike feels unstable and it wanders or wobles under me ...... so maby try a diff road.....

 

[bonanzadave]

.....back (to the regularly scheduled speeding thread). Friggin back tire only had 20 psi. Run up to QT and dialed em both to 36psi. Made some runs. Im really liking these road riders. There is one ramp on my "course" that Im getting comfortable with. Wont be long till Im rubbin the centerstand. Been a long time since Ive done that. Bike is runnin t!ts. (can I say that ?)

So I was able to get the Avons up to temp and then push er up through 6.5K. Felt a little wiggy but I was doing it. Mr. Sk8er dude, I am gonna go find some better road. Traffic was a little much tonight. How fast is 6.5k rpm in 5th ?

When I got back the 36psi in a cold tire was 38 psi. Now I gotta figure where my slow leak is.....

 

[posplayr]

.....back (to the regularly scheduled speeding thread). Friggin back tire only had 20 psi. Run up to QT and dialed em both to 36psi. Made some runs. Im really liking these road riders. There is one ramp on my "course" that Im getting comfortable with. Wont be long till Im rubbin the centerstand. Been a long time since Ive done that. Bike is runnin t!ts. (can I say that ?)

So I was able to get the Avons up to temp and then push er up through 6.5K. Felt a little wiggy but I was doing it. Mr. Sk8er dude, I am gonna go find some better road. Traffic was a little much tonight. How fast is 6.5k rpm in 5th ?

When I got back the 36psi in a cold tire was 38 psi. Now I gotta figure where my slow leak is.....

I changed the tires on my GS750E and left the tubes off with my Avons brand new. After a while it started loosing pressure first the front then the back as well. I pulled the tires off and cleaned the inner part of the rim with fine steel wool (where the bead seats). I then sprayed with silicone spray to coat the aluminum to keep it from corroding. Stopped the leaks.

 

[bonanzadave]

Stopped the leaks.

Mine are tubeless too. The two nuts on the valve stem were loose. I squirted it with simple green and It was blowing bubbles and down to 32psi. Tightened the nuts and the bubbles stopped. Today after work it was still 32psi .

 

[posplayr]

Mine are tubeless too. The two nuts on the valve stem were loose. I squirted it with simple green and It was blowing bubbles and down to 32psi. Tightened the nuts and the bubbles stopped. Today after work it was still 32psi .

Well give err hell .............................



But be careful else the next speed limit in the old girl will show up.

 

[gs road racer]

sprayed with silicone spray to coat the aluminum to keep it from corroding

OMG I believe that to be a very dangerous thing to do. Silicon is an amazing lubricant and should not be used on tire beads. I am very suprised that tire hasn't moved on the wheel if it was a wheel with a tube you might well destroy the tube.Which could happen on hard braking or acceleration.We used to use soapy water to help get tire beads on and seat but had a few slip so the practice was stopped.

Randy

oh btw I'm sufficiently "shocked" now TY

 

[posplayr]

OMG I believe that to be a very dangerous thing to do. Silicon is an amazing lubricant and should not be used on tire beads. I am very suprised that tire hasn't moved on the wheel if it was a wheel with a tube you might well destroy the tube.Which could happen on hard braking or acceleration.We used to use soapy water to help get tire beads on and seat but had a few slip so the practice was stopped.

Randy

oh btw I'm sufficiently "shocked" now TY

So you are saying you have had inflated tires rotate on street wheels to the point where the valve stems were shredded?

I went to see if there was any evidence of "damage"; since it is tubeless I'm not sure how it would show unless it was littlerally spinning on the wheel and heating .

If it matters it was a "dry" silicone spray that leaves a smooth film. It is not wet or oily.

I did it to stop corrosion of the bare aluminum.

 

[posplayr]

apparently anything can start a wobble

http://forum.oldskoolsuzuki.info/cgi-bin/Yabb/YaBB.pl?num=1277466419