I'm confused about the deal with the preloaded motor mounts....why were they done that way in the first place?

 

To force us to buy replacement parts by 20,000 miles? Planned obsolescence?

 

My best guess would be manufacturing tolerances vary, so they just jam it in and crank it down, as opposed to shimming each and every mount. It shouldn't be a problem as the rubber should give a bit, but many have had failures.

 

I believe when the motor mount is preloaded that it removes some of the vibration absorbtion that the rubber mount is intended to do. The shimming was the first thing I did to mine. I did the same thing by simply jacking the motor to remove the weight and then filling the gap between the motor mount and the frame with washers.

 

Not that this is the thread for this discussion, but I'm confused.

If the front mount has the engine loading it already, then you jack the motor and put shims under the motor mount, doesn't that put more strain on the motor mount when the jack is removed?

What am I missing here...there's gotta be something.

 

This will be my next mod. I live in Texas and I need to do everything I can to keep my bike cool.

 

I believe that when the motor mount is in place and the motor is supported there should be no space between motor mount and where it attaches to the frame. If there is a 3/16 space there and you pull the motor mount tight with the bolts you are using up some of the rubbers ability to absorb motor vibration. In otherwords it should be in a neutral state at rest.

 

The mount on mine was being pulled apart, when I loosened the bolts the mount pulled away from the frame as well as dropped down, so I put a jack under the engine, raised it up until there was no resistance turning the bolts by hand, at that point there was a gap between the mount and the frame that I shimmed.

 

I shimmed mine the same way.

 

Oh...the way I read, it sounded as if the motor was pre-loading the mount. But those last posts clarify that it's the opposite.

Is this "relaxing" of the mount done with both wheels on the ground then?