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"Wander" and Tire Shimmy
Kerry Wood
Will fork braces eliminate that awful shimmy when you drive over parallel groves and cracks in the pavement, the kind that make your motorcycle feel like it suddenly it is made out of rubber instead of steel?
Certainly the fork brace helps a great deal by not allowing the forks to flex as much. It made a significant difference when I put it on my bike. However, a front tire can also cause problems with stability. Many bikes I see show significant cupping occurring off the centerline of the front tire which causes the bike to shimmy especially when leaning the bike in a turn. I suggest that you run your hand along the surface of the tire both on the centerline and on each side of the centerline where the tire makes contact with the road when leaning into a turn. If you feel ridges (high and low spots when moving from one tread to the other) then it might be time for a new front tire. Most of the front tires I've had wear out through uneven wear (like cupping) long before the tread itself is gone. Tread remaining shouldn't be the only indicator you should use to determine if a tire is worn out.
The other thing that you need to look at is making sure that your are running the proper air pressure for the current load that your carrying. I recently put new tires on my Big Red and went on a nice ride. My shimmy during turns was gone (my front tire had uneven wear off the centerline) but I noticed that my bike still had a tendency to want to follow every line in the road that it would encounter causing the riding experience to be more "eventful" than I hope for. In searching my brain for possible causes, I realized that I had filled my tires with too much air (the standard pressure I run when riding two up fully loaded).
I pulled off the road and adjusted down my air pressure by around 7 pounds each and my problem immediately went away. Too much air pressure means your contact patch on the road is smaller and therefore more subjected to the small imperfections in the road that we always encounter.
I hope you find the problem. I find it really frustrating when my bike handles weird.
Sid Hansen
I have identical tires and wear on two 78E's. One "walks" over the painted lines and one doesn't. I found that the axle pinch bolt on the rear of the bike had allowed a little slop there. I adjusted it and the problem largely vanished.
You need to check welds very closely also. Other possibilities... Wheel bearings and steering head bearing.
Kerry Wood
Will fork braces eliminate that awful shimmy when you drive over parallel groves and cracks in the pavement, the kind that make your motorcycle feel like it suddenly it is made out of rubber instead of steel?
Certainly the fork brace helps a great deal by not allowing the forks to flex as much. It made a significant difference when I put it on my bike. However, a front tire can also cause problems with stability. Many bikes I see show significant cupping occurring off the centerline of the front tire which causes the bike to shimmy especially when leaning the bike in a turn. I suggest that you run your hand along the surface of the tire both on the centerline and on each side of the centerline where the tire makes contact with the road when leaning into a turn. If you feel ridges (high and low spots when moving from one tread to the other) then it might be time for a new front tire. Most of the front tires I've had wear out through uneven wear (like cupping) long before the tread itself is gone. Tread remaining shouldn't be the only indicator you should use to determine if a tire is worn out.
The other thing that you need to look at is making sure that your are running the proper air pressure for the current load that your carrying. I recently put new tires on my Big Red and went on a nice ride. My shimmy during turns was gone (my front tire had uneven wear off the centerline) but I noticed that my bike still had a tendency to want to follow every line in the road that it would encounter causing the riding experience to be more "eventful" than I hope for. In searching my brain for possible causes, I realized that I had filled my tires with too much air (the standard pressure I run when riding two up fully loaded).
I pulled off the road and adjusted down my air pressure by around 7 pounds each and my problem immediately went away. Too much air pressure means your contact patch on the road is smaller and therefore more subjected to the small imperfections in the road that we always encounter.
I hope you find the problem. I find it really frustrating when my bike handles weird.
Sid Hansen
I have identical tires and wear on two 78E's. One "walks" over the painted lines and one doesn't. I found that the axle pinch bolt on the rear of the bike had allowed a little slop there. I adjusted it and the problem largely vanished.
You need to check welds very closely also. Other possibilities... Wheel bearings and steering head bearing.