Front end wobble when turning right

[Thruxtonian]

Ok, heres a question for all of you knowledgable types, I have a 2007 T100 that has always had a front end wobble. It has about 6500 miles now and the last few rides I've been trying to pay more attention to where its' coming from. It seems that its most noticeable between 35-45 mph and when leaned over to the right. Its also felt to the left, but to a lesser degree. And wobble may not be the best description, its more of an up/down vibration. It almost reminds me of when you pull up next to a Harley at a traffic light, and the front wheel is jumping up and down??? Kinda feels like that. You can feel it through the bars and if I look down I could swear I can see the front wheel moving up and down.

Some background...I purchased the bike new, from a dealer who absolutely botched the PDI and setup. There were so many things wrong with it that it's amazing I kept her long enough to grow fond. One of the things I had done was to install the fork gaitors and I'm wondering if its possible the fork legs were re-installed slightly tweaked, or if maybe one leg has less oil than the other? Do any of you suspension gurus know if that may cause what I'm describing?

The up/down wobble isn't really problematic on its' own, but it does cause me to keep the speed down a bit, and I would really like to be able to get a little more agressive with the bike. Thanks again for any help or suggestions.

 

[Motley]

I'm no guru, but you might try loosening the triple clamp bolts and the axle, to let the forks relax into an unstressed position, then tighten everything back up again.

 

[tv guy]

I'm no guru, but you might try loosening the triple clamp bolts and the axle, to let the forks relax into an unstressed position, then tighten everything back up again.

+1 also-

One of the things I had done was to install the fork gaitors and I'm wondering if its possible the fork legs were re-installed slightly tweaked, or if maybe one leg has less oil than the other?

Yes both could cause problems but if they put the gaiters on one fork leg at a time I doubt they could screw it up much but never say never. They shouldn’t have done anything with the fork oil to put on the gaiters.

It sounds more like a wheel imbalance does it have any weights on it? While you’re looking look at the tire sidewall where it meets the edge of the wheel make sure the tire is fully seated in the bead. If you look it will be obvious the lines of the tire and the edge of the wheel will not be parallel. (this is a bad thing!) Last check the outside of the tire for bulges. It’s rare but cords can separate on motorcycle tires just like car tires.:eeek:

 

[thearcticsea]

Make sure the forks are both positioned the same in the trees. Loosen the pinch bolts that hold the axle tight at the bottom of the forks. Sit on the bike and pump up and down on the suspension a minimum of 15 times. Get off the bike and torque the pinch bolts correctly.

If this doesn't solve the problem, and it probably will, you have a problem with your tire or wheel or a spoke or two.

 

[champ7fc]

If you can, have the runout checked on the front rotor, it may be warped enough to cause what you are describing.

 

[Thruxtonian]

Thanks for all the info! I'm at home with a sick child today so maybe I can have a look when he gets a nap. Does anyone know the torque values offhand?

I think that's gonna do the trick. I'm pretty sure there's no faults with the tire or mounting and it doesn't appear to be a balance thing because of the way it presents more in right turns. Btw, it was delivered when new with a cracked headlight, stuck choke, and clogged carbs caused when the tank liner separated from the neck, requiring a new tank shipped from the UK. So who knows what they may have done while installing the gaitors!!!

 

[drlapo]

my 05 thruxton does that too
I've changed the tires, balanced them, new shocks, trued the wheels, added Race Tech emulators, progressive springs and tried different oil viscosity.
nothing has cured it
it occurrs only on secondary roads and I suspct the front suspension cannot cope with minor surface irregularities

 

[LoVel]

and he still rides like a mad man. :motorbike2:

 

[Thruxtonian]

Well...maybe I should just push harder then...

It's not really a big deal, but I have stock suspension and figured I want to get it as close to correct as possible. Having said that I think I'll be looking into the forks and axle next week, once i find the correct torque values.

 

[strokerlmt]

I like to do simple shit first. I agree with the boys on up the thread....loosen the triple tree bolts and the axle....let everything settle....torque down the tree bolts to spec.....I would take the axle out and clean and re grease.....then check that the spacers are stock and equal.....torque down the axle to specs.
Spin the front wheel....bike on jack or box....and note the rim while its spinning....any woobles in the rim or tire.....measure the distance front the rim to the fork.....I clamp a metal ruler to the fork and spin the wheel to see if the rim touches the ruler at any time....check both sides....
LMT

 

[KingBear]

Thanks for all the info! I'm at home with a sick child today so maybe I can have a look when he gets a nap. Does anyone know the torque values offhand?

I have a quick reference chart with all the torque specs. Send me your e-mail address and I'll forward it to you.

 

[drlapo]

and he still rides like a mad man. :motorbike2:

thank you for noticing

 

[Kirkus51]

Could it be that the spokes aren't trued right?? Or... mebbe the tire needs replacing.

 

[LoVel]

Well...maybe I should just push harder then...

If you do so please proceed at your own risk. That was not a recommendation. Lapo is no ordinary man. :crazy:

thank you for noticing

Doug must get it from somewhere.

I have noticed a wee bit of front end wiggle during high speed cornering with my Scrambler but I figure that is just the dual purpose tires. Will probably go with more road based tires when they need replacing

 

[enGage]

I had my 2004 Bonneville rims re-chromed over the winter so I de-laced them and sent just the rims off to be chromed. Last week I put everything back together and I had a wobble as well. Since the bike did not wobble before I suspected that I didn't get the rim true enough so I removed the front wheel and did the lacing process again, but this time more meticulously and that solved the problem. Perhaps your wheels have gone out of true for some reason or the guy that laced them at the factory did a poor job.