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Handlebar wobbleI own a p-38 with a 16" front wheel. Recently, I loosened my grip on the handlebar. At 12+ mph the handlebar had a wobble from side-to-side. My tires are true and I have not noticed any play in the headset. One bike shop told me that the wobble (shimmy?)was normal in a recumbent since the rider's weight was so far back. Is this correct? If not, what do I need to check on my bike to fix the handlebar shimmy? My closest bike store is a hour away and they have no recumbent experience.
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sounds like a loose headset
From your description, it does sound like the headset has gotten loose. It is probably an ordinary 1" threaded headset, and should not be tough to fix.
There are good instructions on the Park Tool website and the late Sheldon Brown's site if your memory needs refreshing.
Safe riding,
Joel
Wobble shouldn't happen
You should be able to steer the P-38 with a light grip on one handgrip at any speed. Wobble is not permitted!
I have noticed some steering vagueness on a bumpy road at 45 mph downhill with the bike fully loaded for touring! This was due to slight frame flex as I hit bumps. Otherwise it is rock steady.
The statement that wobble on a recumbent is normal is rubbish.
I assume the bike isn't loaded heavily?
I'd be asking Lightning for advice. I'd also check the front wheel spoke tension - if the wheel is 'soft' it could allow an oscillation to start. Similarly if the handlebar is flexy it might allow the problem to occur.
Paul W
P-38
Optima Raptor
Optima Lynx
handlebar wobble
Hi EllenMarie,
When you say you have a handlebar wobble, do you mean that the handlebar/steering column feels loose in its fit inside the fork steerer tube? On my older P-38 bikes, the steering column and handlebar are a single aluminum piece, with a separate aluminum bottom piece attached (I think with Loctite). The bottom piece slides into the fork steerer tube, and there is a narrow slot cut into the top of the steerer tube to allow compressing the steerer with a clamp. I think the clamp is actually a seat post clamp, but I am not sure.
If the clamp got loose, it would let you rotate the steering column/handlebar unit inside the fork steerer tube. This would certainly make it hard to control the bike! But it is not something I would describe as a "wobble".
It is also possible that the fit between the steering column and the bottom aluminum piece - which looks like a machined piece of aluminum - has gotten loose. This might cause a wobbling feeling in the steering. It would also make riding the bike very dangerous indeed.
You write that you checked the headset. Check it again, by locking the brakes while standing still on the bike. See if you can get the bike to rock forward and backward. If it rocks, you have a loose headset.
I guess I'm confused about your wobble. Could you try to describe it again, perhaps in more detail? When you are just sitting on the bike at a standstill, can you feel the wobble by twisting the handlebar in your hands?
It is tricky to diagnose and treat bike illnesses via email, but tell us more and we will try to help. If you are not confident that the steering mechanism is sound, I would not ride the bike until the problem is fixed.
BTW, the stuff about wobble being normal on a recumbent is is pure baloney sausage. My recumbents only feel wobbly if I have had too many beers.
Safe riding,
Joel
Clarify wobble
Just to clarify: My handlebar/stem does not have movement from side to side when I brace the front wheel and try to steer to the left or right. I can't rotate the steering column/handlebar unit inside the fork steerer tube.
When I lock the brakes and push forwards and backwards on the handlebars I have forward/backwards movement in the steering column ....so now, I am leaning towards thinking the headset is loose. The clamp on the steerer tube is tight. When I ride, especially at higher speeds, the whole front end wobbles from side to side. This includes the wheel. I think I may need to curtial my riding until I get the problem resolved.
My bike is equipped with the Shimano Ultegra headset. Would this be a 1" threaded style? If not, what is it? I will go on-line and try to find instructions on how to adjust. A long time ago, I used to adjust and clean my own wheel and headset bearings and I think I still have a feel for when the tightness is adjusted properly.
If all else fails, I'll drive the 3 hours to the store where I purchased my bike. Then, I hope I'll find a recumbent friendly mechanic. I have only seen two other recumbents on the road in my area during the past 4.5 years of Lightning riding. This was during a bike rally where 3,000 people showed up to ride.
Thanks for the help and idea suggestions!
handlebar wobble
A friend had the same type of problem. And what was found was his tires had tire liners in them. These liners were between the tube and the tire. Once he removed them the problem went away.
Gary