700cc twostroke single in RS250

What about vibrations? What is bearable during a race? (i.e. before is self-destructed). I would suspect that th KX uses ruber motor mounts. In addition, the frame in an MX'ers is quite flexible. This should calm down the vibes.

When I was racing in the CMRA, we had a guy who was racing a CR500 super-motard (a friend of mine used to call them super-retard.......). (BTW, they are very popular in France, you can see a bunch of those on the road. I personaly think that they are great to use in the congested traffic of the big cities). He was doing really well. However, he was a very skilled racer. So, it's hard to tell if the results were due to the machine or the rider. Nevertheless, that thing was really reliable. I never seen him DNF.

I forgot to put some pix of the Kahawk. I need to do it soon.

 

Vibration was bearable. There aren't any rubber bushings accept on the exhaust, but it did crack along one of the welds (FMF). The 500s are fast. On top end I had about a 10mph advantage over the KTM525. This was running 17/38 gearing. Large tracks (Road A) would be hard on the motor.