KR-1S.co.uk Forum

I've just swapped my engines over. When I unbolted the old top mount bolt I could see both frame rails expand away from the motor, then mounting the new engine there was 3mm clearance and if I tighten the mounting bolt the frame rails both flex in to the motor. I've checked the manual and parts lost, can't find any spacers or shims. Is this normal on a KR1s?

just shim it so it is`nt stressed ,but keep chain alighnment

fred wrote:just shim it so it is`nt stressed ,but keep chain alighnment

yep, I'd do that to.

Thanks, definitely sounds the best way to go, just didn't know if the frame was deliberately stressed. Thanks for the advice.

When you tighten it up, it closes against the metal tube inserts on the engine mountings, it is supposed to do that.
You can just see the gap in the middle of the spacers, before you torque up the fixing.


The bottom mounting is different, as it is fixed lugs welded on the same tube (with no give) you should shim that one, or it will crack.


Cheers,
Bernie

Thanks Bernie, bottom engine mount is a nice tight fit (looks like yours, only not as clean!)

The top mount had the gap between the steel tubes on the motor, but there was also about a 1mm gap on each outer side between the motor mount end plates and the frame itself. As it all tightened up the frame rails came in probably about 4-5mm to close up all the gaps and I wasn't sure if that's too much? The downside of getting one of these bikes when it's over 20 years old, I've no idea how they were when they were new! No mention of it in the manual as far as I can see.

Think I'll shim the outer gaps closed, the gap between the centre tubes must be normal so I'll leave that.

The gap between the centre tubes will close when you torque it up.
Bernie

you are correct Bernie, I have taken apart and rebuilt a few kr1s and all frames close up to the rubber dampers on the top engine mount, [its the bottom that needs to be tight to the spacer