Re: High speed questions.

Posted by Re-run on Mar 29, 2012; 2:25pm
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/High-speed-questions-tp3866686p3867822.html

First off, these engines would fly apart at that speed in 2nd. In 3rd on my bike, at 70 in third gear, I start to get close to the red. So, I would bet something isn't reading quite right. Top speed however is in the neighborhood of 125. I know it is well over 100, I did it last summer. I was testing my head gaskets before doing my 500 mile run. 150 would not be possible on these bikes without a lot of engine work to increase power to overcome air resistance. Some rickman fairing style work would probably help though.

The speedos were never 100% accurate, average deviation is about 8% or so I think. But it can be anywhere from 5-10 miles off but usually closer to the middle.

As for the shake, you have a number of causes. Your tire could be cupped or otherwise damaged, even if you can see it. If it is out of round a bit or out of balance, you can have issues.
Your rim could be out of round, you need a dial gauge to check this but it would be a good idea, especially if you have spokes.
head bearings could be bad even if they do not feel like it. A quick test would be to sit the bike on the center stand and put weight on the back to raise the front tire. Slowly rotate the bars back and forth and feel for any notching. You should also be able to set the bars just off of center on either side and they should turn that direction on their own with very little pressure. If not, new tapered bearings are in order.

Some new fork oil might be in order too. If the levels are of from each other, dampening can be affected.

And finally, the road you were on, did it have rain grooves cut into it or wheel tracks? Your bike might be fine and those damn things can cause wobbles.
A cheap stabilizer is not a bad idea though but check and correct any issues first.