speed wobbles!!!

[jfeagins]

My money is on your new rear tire causing this!!!!!!!!

Too bad you don't have a center stand - or other suitable means to lift the rear off the ground to observe while running.

Even just a little drag from either side of the front brakes could give you a problem.

WTF? I guess - IF - the rotor were warped badly, it might cause some grief, but otherwise...............cause wobbles?

 

[spursmech]

-35psi front and rear
-im running a 120/90 18 in the front and a 170/80 15 in the rear

but i just found another problem... my rear rim is covered in gear oil!!!! its coming out where the rim and geardrive meet(where those plastice round pieces touch) why would i be leaking gear oil all the sudden?? Ive put 200+ miles on it since i put it back together and never had a leak and now im getting gear oil spattered on my rim:bang head:


Jason

Jason, there is an o-ring in the final drive that keeps the fluid inside the drive. When it goes bad the oil leaks out onto your wheel. Check your fluid soon. Good luck, Spursunk:

 

[magna_dude74]

Good idea, ill do that today, and ill definanlty post back on any findings with my speed wobble and even my tuning problem. Thanks


Jason

For what it's worth, I just changed my pads front and rear, cleaned the pistons as well as I could without takingthe calipers off the bike. At first the front right outer caliper was acting like it was sticking, but now has gone away. I too had problems with the front end wobbling around, this has gotten ALOT better after the pad-slapunk: I did get upto 120 before she started wobbling, this might be caused by stock springs in the front and low PSI in the tubes.:ummm: My thoughts, if the caliper is not seated "true" and the rotor has any run-out, the sudden increase in temp will cause the materials to increase in size. Now what would normaly be just a "brush-by" of caliper/pad, now it becomes a "grab" with every rotation. This constant grabbing at increasingly shorter time frames causes bad harmonics. These harmonics will transfer through the suspension up to the bars.:hmmm: Also there are several variables that we can not rule out like, initial torge when setting the new bearings and the follow-up 2.5lbs spec, when was the last time the torque wrench was cerified? Were your tires installed before or after lunch at the stealership? was the pressure in the fork tubes equal within ?.125 PSI, etc.....
Someone care to challange my thought processs?

 

[65fury]

Well the oil leak is back:damn angry: anyone know a good way to lift th ebike off the ground without a center stand? Although the oil smells like gearoil, but looks like grease:ummm: my gear oil was the regular clear bluegreen color, but whats on my rim is gray/black like the grease i used....:confused2: I replaced all my seals and bearings and "O" rings in the rear so why would it be leaking?


Jason

 

[65fury]

okay im an idiot, i looked at my rear rim again and its just grease thats slowly coming outa there:bang head: no loss of gear oil, i checked:biglaugh: so i guess i got a little grease happy when doing my rear drive assembly. Still havent checked for any play in the rear rim yet, still trying to figure out a way to lift the bike up??? no center stand is really a pain:damn angry:


jason

 

[Shuriken]

Dont know how you guys live with that ****.

It's miserable. It's like having to ride your VMax with a State Trooper on your tail.

 

[65fury]

Well i read some post on speed wobbles and tried pushing against the handle bars at high speeds to stop the wobble and hey it worked!! but if i stop pushing the wobble hits, i dont like trying to do more than one thing at 115mph except staying alive:biglaugh: so what does pushing mean? it stops the wobbles but what does that mean is bad?

jason

 

[mivmx]

Head bearing adjustment. I believe you said you installed new bearings. Did you install new races too? are they seated all the way in the frame? Just some thoughts. It definately sounds like it is in the front end.

 

[COP RUNNER]

well i read some post on speed wobbles and tried pushing against the handle bars at high speeds to stop the wobble and hey it worked!! But if i stop pushing the wobble hits, i dont like trying to do more than one thing at 115mph except staying alive:biglaugh: So what does pushing mean? It stops the wobbles but what does that mean is bad?

Jason

Do You Have Stock Handlebars On The Bike ?

 

[65fury]

Head bearing adjustment. I believe you said you installed new bearings. Did you install new races too? are they seated all the way in the frame? Just some thoughts. It definately sounds like it is in the front end.

New everything:biglaugh: bearings races even new grease:rofl_200: yup made sure they couldnt get seated anymore, ive done my fair share of bearings in the past. Im gunna try to lift the front end tomarrow and do the test how the handle bars fall again just to make sure.

Jason

 

[65fury]

Do You Have Stock Handlebars On The Bike ?

yup sure do... but the bike did 120mph as straight as an arrow with ZERO wobble or anything! before i changed the tires and bearings and such, could soft front forks cause a wobble? cause i feel like they compress to much.....



jason

 

[dannymax]

When you torqued the stearing head bearings was your final torque at the recommended 26.4 in. lbs. (2.2 ft lbs.)? If so, when you do the 'bounce test' it will prolly hit the stops pretty hard, but do your adjustments in small increments and test drive it.

When I put new head bearings in my '06, it needed just a bit more snugging over the 26.4 torque to handle right.

I still would like to see what a 110 Metz ME33 Lasertec would do for your wobble....I went thru the same thing you are (except with a Shinko front) and the ME33 finally corrected the problem.

 

[65fury]

Well i didnt torque those to spec, i had seen Morleys video on the bounce test so i just kept slowly tightening it till it didnt bounce.

jason

When you torqued the stearing head bearings was your final torque at the recommended 26.4 in. lbs. (2.2 ft lbs.)? If so, when you do the 'bounce test' it will prolly hit the stops pretty hard, but do your adjustments in small increments and test drive it.

When I put new head bearings in my '06, it needed just a bit more snugging over the 26.4 torque to handle right.

I still would like to see what a 110 Metz ME33 Lasertec would do for your wobble....I went thru the same thing you are (except with a Shinko front) and the ME33 finally corrected the problem.

 

[dannymax]

Well i didnt torque those to spec, i had seen Morleys video on the bounce test so i just kept slowly tightening it till it didnt bounce.

jason

Did you do a 2-stage torque? Don't recall the 'seating torque' off hand....80 ft lbs or something like that. You have to seat them, then back them off and do a 'finish torque.' No reason why the bounce test wouldn't work fine for the finish torque providing they were seated first.

EDIT: The initial or seating torque is 36 ft lbs. page 6-38 of the vmax service manual.

 

[65fury]

:bang head: ooops didnt do a two stage torque, ill definantly be looking at that after my bike is running right again, still chasing a mid range stumble, ive noticed tho that at WOT itll start wobbling around 90mph if im pulling back on the handle bars or if im not tucked down against my tank cover.

jason

Did you do a 2-stage torque? Don't recall the 'seating torque' off hand....80 ft lbs or something like that. You have to seat them, then back them off and do a 'finish torque.' No reason why the bounce test wouldn't work fine for the finish torque providing they were seated first.

EDIT: The initial or seating torque is 36 ft lbs. page 6-38 of the vmax service manual.

 

[Ricardo]

raises the air pressure in front tire ... find a better performance at low speeds and under full throttle ... try with more than 35 psi