Topic: shimmy in the front end of my 77 750k

[shuswap_rider]

My bike only has 1700 miles on her. In the past year it has developed a shimmy in the front end at 40-50 mph.....it gets worse if you take one hand of the bars.Is it tire related?....I have had it rebalanced..but it did not make a differance.I have also played with the tire pressures..no change??...Also have noticed uneven ware in the font tire.....could this be a faulty tire???

Thanx
Mark

[oldbiker]

Could be the tyre but are you sure the tyre is seated properly? There is a small rib moulded into the sidewall of the tyre and this should sit evenly at the same distance from the rim all the way round. Also a shimmy like this can be caused by wear in the wheel bearings (front OR rear) or in the swing arm bushes.

[SteveD CB500F]

Lots of things you could try.

Read this first http://www.sohc4.us/forums/index.php?topic=165.0

and/or search on "shimmy" or "wobble" to find other threads

Steve

[eldar]

could even be that the spokes are not tightened right. Makes the whole wheel assembly go out of round.

[CB750R]

Front ends are tricky, check the tire and rim for odd wear, or out of true, then check wheel bearings, check the fork to make sure its alighned properly, and then the head head bearings for proper adjustment and no play. if checking adjusting doesnt work, then its replacing and praying! good luck

my bike rode like hell untill I adjusted the head bearings, the previous owner had em torqued down good!! (prolly why he sold it)
it was a scary ride!!

[CB750R]

oh yeah and I'm hoping to ride out to white lake on the 22nd on my 77 750F !!

[Uncle Ernie]

Often times on older vehicles the air in the tires needs to be change along with the oil and air filter.  OK, well, it worked on a friend of mine once...
A lot of shops don't "get" tube-type tires and don't set the bead right- they're used to the tubeless type that are faster to mount.    Check steering head bearing adjustment; on the centerstand with the front wheel off and no impediments from cables, lightly push the wheel from left to right. the wheel should fall easily. Another sign is if you feel like you're falling rather than steering in corners.  Check wheel bearings fore and aft.    Check rear suspension for mushiness/ swing arm for good bushings/bearings.  Do you have bags or top box on the back/ Get rid of the top box for sure (weight should be as low and far forward as possible. That's a big reason why any passenger should be holding on to you- not grab rails). Do you have at least 32lb of air in the rear tire?         That's all I can think of.

[eldar]

Ernie gave me a thought. The TIRE may be mounted ok but if a person is not carefull, the TUBE can get twisted. This can cause an uneven spot not noticable by eye. It could cause the wobble.