Springer front wheel bouncing up & down

[RR2]

Weird problem on new build,wheel bounces at 30-40 mph-not before or after.Frame,front end was pro inspected & straightened before build.I previously wrote long thread & it timed out I guess,disappeared.Wheels were totally rebuilt, new tires,twice.Switched wheels front to rear,same bouncing problem.New colony rocker rebuild kit,disconnected shock. No play in front end. Any ideas? thanks

[Rubone]

Was the wheel assembly balanced with the tire on it?
How much air pressure is in it?

[RR2]

Wheels were spin balanced with tires on, 30 psi. Smooth paved roads.Coker sent me another new tire,no charge except for shipping.

[RR2]

Wheels were spin balanced with tires & drums on @ 30 psi. Coker sent me new tire to replace,same problem.

[Sargehere]

Suggestion for timing out: compose your long posts in "Notepad" on your computer, with "word wrap" on so you can read it. Just before copying and pasting your composition in to the thread, here, turn word wrap OFF, up above, and it won't come out all double-spaced on you.

Sounds like a wheel balance problem, 2me. When you dynamic balanced the wheels, that doesn't normally include your (probably) cast iron brake drum, which is also part of the rotating mass, and not particularly balanced. I had a wheel that bounced like crazy starting at 75 mph. 'Changed the position, rotated, of the front brake drum and it settled a bit, but never went away completely. Hope this helps!

[knuckleheadtim]

Most spin balancers use cones on each end to center the hub, which does not work on star hubs. The tophat on the star end depends on the diameter of the axle to position it concentric to the spool. Without the axle, the tophat floats radially and can't be used as a center for a cone on a balancer. You might have better luck removing the cork seals and static balancing the wheels on an axle.

Also, carefully check the bead all around the rim to make sure it's consistently seated. If the bead wasn't well lubricated, it can take excessive pressure to properly seat it.

[vph-d]

Both cars and bikes with balance problems exhibit a shaking situation at about 45 mph. Lift up the front wheel and spin it by hand to see if it stops at the same place.
VPH-D

[Tom Wilcock]

Does tightening the ride control help or is the springer the later one with the shock absorber? Tom AMCA#381

[upsrod]

Try lowering the air pressure. The book calls for 12 lb. on a 500-16....I run 18 lb. in mine. Mine are Goodyears and they hop at 30 lb.

[Chris Haynes]

Try lowering the air pressure. The book calls for 12 lb. on a 500-16....I run 18 lb. in mine. Mine are Goodyears and they hop at 30 lb.

H-D recommends 12 in front and 16 in the rear for a 5.00 x 16. This is based on a 150 pound rider. For each extra 50 pounds increase pressure of rear tire 2 lbs and front 1 lb.

The old riders rule of thumb was 1 pound for each inch of rim. 16" rim = 16 lbs. 21" rim = 21lbs.

[RR2]

Thanks Guys,I just had them off again & had balanced double checked. I will reduce air pressure from 30psi to 15. appreciate the fast help!

[RR2]

put the wheels back on & let out some air to 15 psi. Took it for a 10 mile ride & big difference. 80-90 % improvement! Will do some more tweeking with other components. Can't get any easier fix than that, thanks again to everybody.

[Steve Slocombe]

The ride control usually takes care of this pogo-ing, which I've also experienced at similar speeds on newly rebuilt bikes. The steering damper deals with any side to side shimmying. I don't run tyre pressures as low as 15 psi because I think we are all heavier than we were, and the tyre manufacturing technology has changed a lot in the last fifty years.

[Chris Haynes]

I don't run tyre pressures as low as 15 psi because I think we are all heavier than we were, and the tyre manufacturing technology has changed a lot in the last fifty years.

Note the that the Riders Handbook asks you to add two more lbs for every 50 lbs above 150 lbs of rider weight. Hmmmn. I should have 16 lbs instead if 12.