vernier style iso = vibrations
- Thread starter Snakepit
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If you are happy that all new parts have been fitted correctly then it may just be that the new rubber bushes are stiffer than old aging an crumbling ones you have removed an even if you fit new shim type version of ISO the vibration will still be there dew to new stiff rubber bushes.
I would double check all is fitted correctly an if so maybe adjusting the clearance may help reduce the vibration or move the RPM range where it happens.
I would double check all is fitted correctly an if so maybe adjusting the clearance may help reduce the vibration or move the RPM range where it happens.
Whats your headsteady?
Pull the tank. Loosen the three bolt into the head at the headsteady mount. Sit on the bike and while under weight snug the three bolts and give it another go.
Also, give them a chance to settle in a little and recheck after some riding. Check your clearances with the bike supported on the frame, not on the tires or the centerstand.
Pull the tank. Loosen the three bolt into the head at the headsteady mount. Sit on the bike and while under weight snug the three bolts and give it another go.
Also, give them a chance to settle in a little and recheck after some riding. Check your clearances with the bike supported on the frame, not on the tires or the centerstand.
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- May 28, 2003
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Unfortunately vernier adjuster and one piece iso assembly are two separate issues on one component .
Please differentiate for us. Is it a ONE piece tube/iso assy with threaded vernier adjustments on the end.
http://atlanticgreen.com/images/frontiso.jpg
Or is it the add on adjusters only that REPLACE the original shimming devices only. AKA Mick Hemmings type (designed by an american and given to mick for production/sale). I would consider one of these.
The original built up soft ISO's are great in my book.
My guess you got suckered into the one piece jobbies which I have been a NON fan for well over 20 years .
I wouldn't put them in my bike if FREE..........
You can have soft ISO
You can have hard ISO
If you over tighten the adjuster you have NO ISO.
IMO, best if assembled CLEAN and dry so dirt won't stick and grind the parts to pieces. :mrgreen:
Please differentiate for us. Is it a ONE piece tube/iso assy with threaded vernier adjustments on the end.
http://atlanticgreen.com/images/frontiso.jpg
Or is it the add on adjusters only that REPLACE the original shimming devices only. AKA Mick Hemmings type (designed by an american and given to mick for production/sale). I would consider one of these.
The original built up soft ISO's are great in my book.
My guess you got suckered into the one piece jobbies which I have been a NON fan for well over 20 years .
I wouldn't put them in my bike if FREE..........
You can have soft ISO
You can have hard ISO
If you over tighten the adjuster you have NO ISO.
IMO, best if assembled CLEAN and dry so dirt won't stick and grind the parts to pieces. :mrgreen:
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- Oct 19, 2005
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Yep any and all of the above are the obvious low fruit to pick, just keep in back of mind with fretting, that Norton had to slice the first rubber cushions in half, *three times*, before they could get isolation below 2000 rpm as reported by Frank Damp an original test rider. If not for pleasant bare minimum rubber mass and surface area hysteria phenomenon there'd be nil market for swash plates or radius rod links. They do look the right stuff parked at rallies though.
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- Oct 19, 2005
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Further food for thought and music to my ears was quizzing a good many live and late Commando racers and land speeders to be told there was no handling issues to surprise them as fast as they could go. These of course were all 750 frame folks with drum or RH discs or duals. A bike supported under frame but in riding posture can teach some things about masses hung on fork and nil gryo influence. Air time also instructs on nil gryo influence to factor in while moving axle full arc in plane of travel. Too bad gryo stabilizing ain't enough to eliminate some seeking fork dampers modern to vintage. Live it up and use it up > let the rear rule the roost.
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- Oct 19, 2005
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Ugh another Norton manual wisdom a thinking fella must decide on, similar to retaining chain oiler or topping off oil tank or primary to listed levels. It takes me about 10-20 min on reaching pavement on my SV650 to be annoyed by the mere valve train vibration getting through. If Commando's not operational for a while it 20 min but if switching back to Combat in same week about 10 min. Could try an experiment for us by narrowing the iso head steady cushions area of contact to see if nulls the transmission yet still steadies.
grandpaul
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All I know is "by the book", greased, my '75 MkIII is quite smooth up through 80 until it runs out of gas.
...then it is very heavy and hard to push (don't ask)
As the speedo on my Dreer prototype is inaccurate, I can't say up to what exact speed (definitely over 80), but it is even smoother and completely stable through the twistiest of twisties, widest high-speed sweepers, and whatever else comes along (although I attribute the additional smoothness to the Taylor top steady, Eads front steady, and modern suspension).
...then it is very heavy and hard to push (don't ask)
As the speedo on my Dreer prototype is inaccurate, I can't say up to what exact speed (definitely over 80), but it is even smoother and completely stable through the twistiest of twisties, widest high-speed sweepers, and whatever else comes along (although I attribute the additional smoothness to the Taylor top steady, Eads front steady, and modern suspension).
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- Oct 19, 2005
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Ah so Paul don't I know, with head and breast steady it should feel secure and inviting, till frame twisting loads then the rump rod takes over. The fella's on past nice NOC list and ongoing Brit Iron list were complianting they were balder after trying to adjust various 3rd isolastic type mount not to annoy the snot out of them, expecially those that had to deal with a city before open hwy reached. Just pitch into the turn with help pushing on bars while throttling but thoughtless on fork direction does it for me.
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