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so...question here... whenever im goin between 45-55 my front end shakes like CRAZY! speed wobble crazy so..say i let go of my handle bars at 55 and as it decelerates, it shakes more and more, but if i can make it below 45 it stops completely, or if i let go any faster then 55 it wont shake till it gets down to 55..im pretty stumped on this...not that i just sit there and just let go of my bars all the time... but i spend alot of time in that speed range around town and i can feel it pretty good in my hands...feels like im gettin arm pump and im not even on a dirtbike...any ideas??

Thanks,

I have no idea how to help, but mine is doing the exact same thing, so i'll be watching this thread closely.

An out of balance tire can cause this. I have seen this in car tires. May be worth a try to have the balance checked at a good tire shop.

I'm had a similar issue on my '85 Honda Interceptor....turns out it was missing a balancing weight on the front tire.

Tyres that are out of balance can cause premature wear of wheel & steering bearings, maybe fork bushings/seals, and uneven wear on the tyres themselves. Get the front end up, spin the wheel and check for any obvious run out on the wheel and tyre, and for any play in the wheel bearing, same applies to the rear wheel, then get both front and rear wheels balanced.

mawler wrote:Tyres that are out of balance can cause premature wear of wheel & steering bearings, maybe fork bushings/seals, and uneven wear on the tyres themselves. Get the front end up, spin the wheel and check for any obvious run out on the wheel and tyre, and for any play in the wheel bearing, same applies to the rear wheel, then get both front and rear wheels balanced.

Hi,
well tyre balance could be a factor, but most tank slapper type action appears at the front but is actually generated at the back.

In your position I would be looking at wrong torque on the swing arm bolt, worn swing arm bushes wrong torque on the rear axle, poor alignment of the axle 1/8 of an inch left to right will do this , worn rear wheel bearings.
Having made sure all this is in spec, check tyre pressure , tyre seating on the rim, and "spooning" of the tyres & steering head bearing play as this can be caused by any of the above.

To Geo's and Mawler's excellent advice, I will add:

Check your brakes for drag/warpage

hum....well it looks like ive got work to do...got alot of things to check, thanks for the imput everyone.

I'd check the front end balance. Take the wheel off, put the axle through and put either end of the axle on a jack stand. Spin the wheel. If the same spot ends up at "6 o'clock" after 3 or more tries, it's out of balance. You can balance it yourself using this method. The higher the number of times you spin it, the more accurate you will be in identifying the "heavy spot".

pefrey wrote:I'd check the front end balance. Take the wheel off, put the axle through and put either end of the axle on a jack stand. Spin the wheel. If the same spot ends up at "6 o'clock" after 3 or more tries, it's out of balance. You can balance it yourself using this method. The higher the number of times you spin it, the more accurate you will be in identifying the "heavy spot".

yea... checkin the balance seems to be the easiest thing to look into first.. excpet ive been lazy lately.....

Actually you can probably do it without taking the front wheel off. Just get the front off the ground and remove the brake calipers.

Front end shake can be bad steering head bearings, especially if you are a 'wheelie king' and crash land a lot. Like someone else said take the bike and get the front wheel off the ground.

1: with the wheel off the ground, grab the forks, and try to pull them forward and back, side to side (should not be able to do this).
2: with the wheel off the ground, turn the forks from side to side , Should be smooth without any 'notches' in the center.

are the forks in the same position as before this started occurring? When I was racing flat track and we dropped the fork tubes in the tripple clamps the bikes would shake like a BEAST!!!!

The minute we dropped them back to stock it would get better, but because they were honda's it was still there unless you were on the gas or on the brake.

smokinbunta wrote:so...question here... whenever im goin between 45-55 my front end shakes like CRAZY! speed wobble crazy so..say i let go of my handle bars at 55 and as it decelerates, it shakes more and more, but if i can make it below 45 it stops completely, or if i let go any faster then 55 it wont shake till it gets down to 55..im pretty stumped on this...not that i just sit there and just let go of my bars all the time... but i spend alot of time in that speed range around town and i can feel it pretty good in my hands...feels like im gettin arm pump and im not even on a dirtbike...any ideas??

Thanks,

Did you get what was causing this sorted?

yamaha_george wrote:

smokinbunta wrote:so...question here... whenever im goin between 45-55 my front end shakes like CRAZY! speed wobble crazy so..say i let go of my handle bars at 55 and as it decelerates, it shakes more and more, but if i can make it below 45 it stops completely, or if i let go any faster then 55 it wont shake till it gets down to 55..im pretty stumped on this...not that i just sit there and just let go of my bars all the time... but i spend alot of time in that speed range around town and i can feel it pretty good in my hands...feels like im gettin arm pump and im not even on a dirtbike...any ideas??

Thanks,

Did you get what was causing this sorted?

when u mentioned that front shakes can be caused by something in the rear. 1 of the thing i realized was that my chain was kinda loose... so finally got that tighten up, which seems to have fixed it a bit. but i seem to have side to side play in the chain so i think thats still causing it do shake... and by now my front tire is all chopped up from the cupping. id imagine that itll go away once i get a new chain/ sprockets set up and a new tire itll be better again.