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Discussion Starter #1
Ok I need all your combined brain power for this problem.

I've got a V-Max at the shop that had a new front end installed on the bike. (I didn't do the work). I had a customer come by tonight to try the bike out and he complained the front end wobbled when he took his hands off the handle bars at any speed above 30mph.

I'm thinking the front-end needs to be tighten down a little more on the triple tree to provide a little more dampening. I've read that some bikes will wobble without ribbed front tires.

I plan to have the front tire checked for balance and check for slop in the triple tree. I didn't feel any slop but that maybe something that is not easily detected while the bike is on the center stand. The front wheel is straight and true.

The last thing I can think of is maybe the fork seals may be a little sloppy but I'm not seeing any oil leakage. For good measure I will change the fork oil out to ensure that setup correctly.

Again - I didn't put this front end on the bike - so I'm looking for ideas to check and not a head bashing.

Ok guys - am I missing something to check???
 

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Steering head bearings in good shape? Are they adjusted in the steering stem to spec, i.e. are they snug enough, too snug?

Craig
 

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Junkyard front end correct?

Check balance, wheel bearings, damage to tire itself from previous life(curb, bumper hit)

Bent, warped rotor

Fork tubes not aligned in triple clamp, i.e one higher than the other

New or at least non-crashed steering stem bearings right?

How hard was the hit that knocked the front end off? Is the steering head tweaked?

Or maybe he should leave his hands on the bars...
 

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I'd go with steering head bearings. I think the V-Max came standard with tapered rollers. I bet whoever replaced the front end did not replace the outer races and they were dented by whatever wrecked the original front end. Another possibility is that the frame neck is twisted.

Ken
 

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Discussion Starter #5
More info on the subject -
I checked a vmax form site and apparently this is a common problem for vmax's especially when the front end has been modified or worked on. There is no one item cure for this problem but a process of checks and adjustments. The check items include damper adjustment to the front bearings, proper greasing of the front bearings, fork alignment, fork height settings, front wheel balance, front tire wear pattern check and fit and finish of the fork bolts installation. One guy went as far as installing a new fork brace from UFO claiming the standard brace is not strong enough.

Looks like I'll have to tear the front end off the bike and start from scratch followed by several test rides to cure this problem. Thanks for the input - looks like I'll be inspector Clueso for the next few days.
 

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those all sound like good ideas. start there. V-max notoriously spindly up front. also do not remove both hands from handle bars at any speed below or above 30 mph.
 

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Discussion Starter #7
More follow up on the evil wobblies...
Following work items
- pulled the front end apart and rechecked the neck bearings
- checked to make sure all the correct spacers were where they are suppose to be.
- Re-tighten the front end nice and snug but not too snug
- Move the forks up on the triple trees about 1/2 and ensured they were even
- Checked the front-end to ensure they are straight.
- Checked the front wheel for trueness - it was about 13 thousands off.
- Re balanced the front tire with a spin balancer.

After all that - I can now get it up to 40 to 50 mph before the wobblies start. An improvement but not a cure yet. My next move is to check the front disk. Other than that, I'm running out of ideas for a fix. I checked the V-Max Form site for more ideas but they didn't have much to offer other than the problem can exist and do everything I've already done... This bike was not hit on the front end and the frame appears to be straight. What am I missing????
 

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How is the front tire? It usually causes a problem on decell but could be an issue. Any sign of cupping or uneven wear? How about adjusting tire pressure?

Ken
 

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Discussion Starter #9
Front tire is new with no unusual wear with 32psi for pressure.
 
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