Bonneville America Forums Forums Technical Forums General Tech low speed front end shudder

I have a low speed front end shudder. The bike is a 06 Speedmaster with 2k miles. The wheels have been replaced with America laced rims. The tires are Metzlers with 2k on the rear and 7 miles on the front.
I notice the shudder at 5 to 15 mph. Any faster and it is not noticeable. The shudder happens under power or coasting with the clutch in (or in neutral). In is not a constant shudder - it comes and goes every 2 or 3 seconds and last for 5 to 10 seconds. I did not replace the bearings on the America rims. They "seemed" ok to me.

Tires/Rims are balanced.

Braking front or rear does not start or stop the shudder.

Need some help here fellas -

I'd try a new front tire first.
Then check the rim for true.
Or go faster than 15.
Hope this helps,
Uncle Charlie

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I notice the shudder at 5 to 15 mph. Any faster and it is not noticeable. The shudder happens under power or coasting with the clutch in (or in neutral). In is not a constant shudder - it comes and goes every 2 or 3 seconds and last for 5 to 10 seconds.

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I'm having a hard time understanding the driving conditions that keep you between 5-15 mph for ANY length of time, unless it's in a parking lot. At that low speed I'm surprised there's any shutter at all given that the wheels are barely turning.

I was gonna say take your hand off the bars to see if the shutter increases but NO, NO, NO.... not at such a slow speed!

I had a shudder at 60mph......... It's a "BIG" NO NO to take the hands off the bars at that speed.. Any how, mean while back to this post.. My dealer told me that they have seen some metz. front tires with this condition before..I could see the tire itself wobble and the rim was fine.... New tire.. Good to go... Good luck, and it's better to have it at slow speed. V.

I also have a slow speed shudder/bounce with the Metzeler front tire that I put on last year. Didn't have any issues with the previous Metzeler or Dunlop front tires. It goes away once I'm above about 20 mph, so the only time it's really noticeable is the half-mile in my neighborhood.

Keep an eye on your tire pressure; mine is worse when the front tire pressure gets low. I keep it at 36 psi and it's hardly noticeable, but I get more slow-speed "bounce" even when it's only at 34.

Will

I have searched around the forums and found a couple possible solutions. First, for me, is my chain might be to tight. Theory on this one is there might be a tight section of the chain. Second, again for me, is the front bearings. Have already ordered a bearing kit from allballs. Third, is a punt and a new tire. The current front tire is brand new but the front wheel is used (but new to me). The used rim was unlaced and powder-coated. Then laced and trued. I watched the guy true the rim, so I am pretty sure it was done right.

The reason for driving slow - is just putting around the neighborhood and ops checking my new build.

More riding, diagnostics and testing. Chain tension was not the issue. Neither is the steering head bearing.

The problem feels more like the front brake is grabbing between 10 and 20 mph. But putting on the brake(s) does not stop the grabbing feeling.

Hopping it is the front wheel bearings. Should have new ones by mid-week.

Tod, is it kinda like a 'lop' in that front wheel? (lop - to move in a halting way)

Before you do anything else you might check the front rotor for true while the wheel is still mounted. Some of the riders here have experienced warped rotors so it's worth a look.

Yeah I checked the rotor it is Ok.

Not sure what a lop is.. Think of it as a light braking with a brake/rotor that is not grabbing 100%. Just enough to feel the vibration in the bars but not enough to slow the bike all that much.

That does sound like a warped rotor. If your bike is less than two years old and it is a warped rotor, it should be covered under warranty. I know that mine was.

One more thing, double check your front tire for any defects.

I replaced the front bearings today - no dice.

Also backed out the front caliper so that it would not touch the rotor (warped rotor test)- that did not fix it either.

And aligned the rear to the front tire - notta. Amazing how off those little adjusters are off (total distance out from left side to right side).

Leaning more toward the front tire.

But going to play around with the rear tire, just to be sure, this weekend.

Backed out the rear caliper so that it would not touch the rotor (warped rotor test) - nope

Re-greased the axles with a Molly grease -not that either.

Must be the front tire.

Replaced front tire. Did not fix the problem.

Seems like you've returned the front wheel to brand new so it's time to look elsewhere; any chance the forks are binding?

Just one theory I'll throw out here, seein' as how I haven't yet seen it touched upon here...Have you checked your front to rear wheel alignment with a perfectly straight piece of wood or other such implement?

Ya know, ya really can't count on those little marks on the back of the swingarm that are supposedly there to use as a reference when adjusting the chain to be true "north-south" on the bike.

Sorry Todd, I just saw your line, "And aligned the rear to the front tire - notta. Amazing how off those little adjusters are off (total distance out from left side to right side).", above, and so I guess you have already thought o' that.

(sorry, I'm all out o' ideas here)

Me thinks it may well be your brake caliper / piston seals !
Not releasing fully at low speed

There was a post a short time ago,,,,,,

The person took to dealer,,,,,found fork seals(stick-tion) needed to be "broken in".

his problem went away after 2500-3000 miles

I have an 07 Speedy w/9K on it. Have had that "shudder", mine is more of an out & out wobble, not bad, but definitely an unwanted characteristic. It happens when I, for instance, am going 40, take left hand off to open choke after warmed up. Definitely cannot take both hands off, & it is a wobble. Tire pressures 35#, had dealer check front forks, wheel, etc. Still there. I love everything about this bike but that. Have an 05 Sporty, no problem, an 06 T100, no problem, an 00 Legend, no problem. Demo'd a new Rocket, Thunderbird, all sorts of stuff, the Speedy is the only w/the issue. Oh, yeah, the dealer knows people have had the problem, but no solution.

it's not something as simple as the wheel balance? has the wheel balance weight come off?

interesting read...

Motorcycle Dynamics By Vittore Cossalter