Shim issues....need advice!

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Hi Gents MKIIA

I couldn't find a similar situation in past threads.

I just put the engine back in the frame, reinstalled bolts shims etc for the isolastic mounts.....torqued both to 25 lbs...and I have zero clearance on either mount.

Just before I took them off many moons ago, I decided to check them for clearance just for the heck of it,and they were .010, all good.

I kept everything filed away in the order that I took them apart, just gave them a good cleaning and lightly greased.
I've taken the bolts out twice already and reinstalled just incase something was stuck or something.
Same result.

I didn't disturb the rubbers in the mounts during this project.
Kinda baffling!

Any thoughts please and thanks!
 
Take it for a ride and see if your clearance comes back when things get shook into place. Jim
 
"Just before I took them off many moons ago, I decided to check them for clearance just for the heck of it,and they were .010, all good."

There can be some variation checking them on the bike depending on how you actually did the measuring - levering the engine over to one side with the bike on the side stand as opposed to raising the bike by the frame, etc. Maybe you applied more "lever" back then then you are now. Or maybe, if done on the side stand, the amount of lean (and therefore engine weight) is different due to to how the handlebars are oriented and therefore the amount of force required to lever the engine to one side is now greater. The torque on the bolts will have some effect as well - maybe they weren't as tight as they are now? The combination of all this could result in .010 difference. ALSO, depending on how the mounts/shims were stored, the shims may have rusted a bit making the shim(s) slightly thicker and reducing the clearance.

These shims/vernier adjustment is not an exact science! It's a bit closer to that, at least for the front mount, if it is removed and the clearance set up on the bench.
 
Did you paint or powdercoat the front mount and cradle? With powdercoat especially, if there's any on the ends of the tubes it will throw your old clearances off. It's a good idea to get down to bare metal on all the surfaces where the iso's and hardware come into contact with the cradle and mounts.
 
All points taken....and I will give them a whirl.

Thanks so much fellas!

Right now the frame (powder coated) is in a sling and homemade stand.

Taking 'er out for a spin (been 10 years...can't wait) might get everything settled in.
 
I think Bob has a possible answer to this, I remember losing all the clearance on my front mount some years ago after doing some paintwork,

Dave.
 
Forgive my ignorance, but why .010".
I always set mine to as near zero as possible, making sure that the shim carriers can still rotate proving they are free to move.
I cannot see why more clearance would give you less vibration or better handling.
Surely less clearance for more predictable handling.
 
Surely less clearance for more predictable handling
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Yes but more chance of vibration!
Dave.
 
I like .006! But I admit I probably couldn't tell the difference between .005 and .007!

Re powdercoat...as Bob noted, that could be it. I've always considered powdercoating to be a tool of the devil. :)
 
Make sure your end caps are on all the way, make sure you can reach down and make them turn, rotate.

Sometimes they get galled in place, I had to take sandpaper and remove the sticking points so they could turn freely.

By end caps I mean the caps that fit over, with a lip, your actual iso tubes, and then the shims are outside of them in the order.
 
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