Iso trembles?

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Hi fellow Commando pilots. My '74 850 runs beautifully smooth at freeway speeds 65 / 70mph, very minor vibes through the seat. Rolling off the throttle down to around 2500 / 2800rpm the bike feels like it has square wheels. I fitted Mick Hemmings ISO adjusters along with new ISO rubbers quite some time ago and got the bike pretty well set up. The head steady is the original set up as supplied by NVT. Could the roughness be caused by the head steady?, any other thoughts?. Thanks and ride safely. James
 
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Kind of like the Doctors reply, then don't do it... Down shift and keep the RPM's up above that spot.
Can it be made better? Yes.
Will it require a lot of digging and careful work? Yes.
Will it go away completely? No
A perfect spark and a perfect set of carbs helps the most.
 
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Iso trembles

Hi norbsa, thanks for the reply. Not sure what you mean, I roll off the throttle to exit the freeway, slowing down etc.. My ign. and carbs. are set up spot on. Does the head steady control side to side rock or fore and aft rock?. thanks. James
 
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James,
The Mk3 spring thingy that fits in front of the head steady will help get rid of those vibes. It lifts the motor up taking the load off the front ISO.

The link type head steady can be supplied with this device and with a little care those vibes can be completely dialed out.

Cash
 
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James this is what I did See this and other pics there. http://groups.msn.com/Brit-Fe-Pics/shoe ... hotoID=227
Wendy AKA Bill made the parts.See an old thread on this. When you think it through the top brace has the greatest effect on keeping down the hinged effect in hard turning it's the point furthest from the force of the rear tire patch.When you get something there that can move freely up and down and only .002 side to side and is built heavy enough to handle the force. Well you are there.
 
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I replaced my old head steady with a dave taylor link system and it really made a difference in the way the bike handles. It still has that wounderful shake but not enough to be a problem. I wouldn't want it all gone. I also shimmed my isos to about .002 clearence.
 
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iso trembles

Hi fellow Commando pilots, thanks to all for the feedback. Looks like a new head steady is on the cards. I have a new c.n.c mill at work in need of a work out. Thanks again. ride safely. James
 
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