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joe madridSat Dec-07-02 08:04 PM

  
"isolastic motor mounts"


  

          

i know i need the motor mount that mounts at the back! should i replace all of the isolastics or just the one that is bad? so are the new style (850cc) isolastic motor mounts really worth installing on a 750? or are the 750 style adaquate. is it a worthwhile update?

  

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jack henrySun Dec-08-02 11:35 AM

  
#1. "RE: isolastic motor mounts"
In response to Reply # 0


  

          

I put the vernier isolastics on my 850 and they work great. bought them from Norvil in England..sure saves a lot of guess work..

  

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dynodaveSun Dec-08-02 11:35 AM
Member since Mar 18th 2009
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#2. "RE: isolastic upgrade or degrade?"
In response to Reply # 0


  

          

I fear that to many people fail to realize that later rubbers and especially the MKIII adjustable ones are at least twice as stiff as original 750 rubbers.
You can see the deflection rates in one my articles.
The key to isolastic is it's ability to move when a force is applied and therefore not transmit the energy to the frame. My MKIII vibrates at least 3 times as much and to a higher RPM than my combat. New hard rubber iso-mounts are someting I won't put in my bikes.
I would seek out and use early style soft iso rubbers.

  

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Brithit IISun Dec-08-02 09:26 PM

  
#3. "RE: isolastic motor mounts"
In response to Reply # 0


  

          

You're bound to get lots of advice on this. If you are going to do the rear mount, you might as well do the front one too, since it is far easier. If you have a stock 750, you will probably find when you tear things down, the inside of the Iso tubes are all rusty, as are the shims etc. You might as well put it all in new. I bought "super soft" (their term, not mine) isolastics from Fair Spares America about three Years ago, and I really like them. Dead smooth at anything above 2,500 RPM. You no longer have to machine the front motor mount to fit these things. The last time I posted on this subject, some naysayer told me that me that my bike probably handled like it had a "hinge in the middle" because I used the procedure that Fair Spares says to use to adjust them. Basically, you tightnen then, back them out a half turn, and that's it. Bike handles great, vibes are gone, it's a good and worthwhile change. When you have the rear apart, check your swingarm bushes, and rear spindle for wear and movement, there will never be a better time to look at it. Like almost every Commando subject, many will say their way is the "only" way, and all others are wrong. I can only tell you what I spent my money on, and it worked great.

  

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usrjdSat Apr-15-06 04:30 AM
Member since Mar 18th 2009
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#4. "RE: isolastic motor mounts"
In response to Reply # 3


  

          

Hi

I've just joined the forum and need some help on setting up the vernier isolastics. The instructions tell me to tighten up the adjuster, then back it off half a turn - but this gives approx 20 - 25 thou clearance. Not the 10 thou of the old shim system.

Is it 10 thou a side (i.e. 20 thou in total) or should it be 10 thou and hence much less than half a turn.

Baffled of Melbourne...

Thanks all

Rich.

  

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dynodaveTue May-16-06 01:37 PM
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#5. "RE: isolastic motor mounts"
In response to Reply # 4


  

          

The spec is for .010" total.
This is checked after you tighten the 1/2" through bolt.

I measure mine with a dial indicator clamped to the frame and the pointer on the engine. I grab the header pipe and push/pull to deflect the iso's. while reading the end play.

  

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