please help! '11 FXDB, now has wide glide trees,21" Harley typhoon front wheel,180 rear,16"apes. Since rebuild in dec. has a severe high speed wobble. Have checked tire pressure,balance. Have adjusted neck bering according to manual. It was @ 65-75mph on highway. Now is also in sweeping curves and anything above 60mph. I've had several close calls recently w/ deceleration to control this.

 

Hi from the UK and welcome to HDF. You've now got a 21" wheel, which is less stable than your stock 19" wheel, in addition you have high bars, plus a wider tyre than stock. IMHO those three things are conspiring together to make your bike less stable.

As speed increases while you are riding, so also does wind noise. That makes you grip the bars tighter. With your high bars you are like a sail on a ship and being buffetted more than before, which adds to the problem. It is likely that some of the wobble is simply you holding on too tight. Been there!

Add to that you have non-stock tyres, which are probably not inflated correctly and you have a recipe for instability! What width rim and size of rear tyre do you have?

 

I have to disagree with the high handlebars being a cause for wobble. I've had my bike with 16" apes at 100 mph without an issue and normally ran it between 85 - 90 mph.

I am sure that I've missed a few things to check for on this list, but it is a start.

Everything that needs to be checked for the wobble should include, but not be limited to:

• Air Pressure
• Rear Wheel Alignment 0.793mm In Between Side To Side
• Tires Not Balanced
• Rim / Tire Out Of Round
• Steering Head Bearing Incorrectly Torque
• Wheel Spacers
• Wheel Bearing
• Engine Mount
• Transmission Mount
• Equal Amount Of Fluid In Both Forks
• Loose Axle Nut
• Caliper Alignment
• Neck Bearing Adjustment
• Swing Arm Pivot
• Shocks Rear Aligned Equally
• Top Of Forks Not Extending More Than 10.66mm - 12.7mm And Be Equal
• Steering Stem Nut
• Swing Arm Bushings