b40rt

Have you tried changing the valve core ?

Dremmel

If your plug is sooted at 200 : I , its more likly its running rich than anything to do with 2 stoke oil.

Driving 700 each way is my record, so far...

#ridgrunr, move to the uk, ride pre65 or twin shock - problem solved.

Check for air leak first, inlet tract if loose could be the problem. Not sure if climber disc valve timing the same as air cooled, if it is - lock crank at TDC, disc is just starting to cover port. I'll try and find the diagram. Sure Martin has it somewhere on his site.

Why would you consider using water cooled clearances on an air cooled engine ?

I thought your rotax lived under a bench !

Re ATF, have a read

Never used ATF in a rotax, but have used it for years in a BSA clutch with no ill effect. Don't think this is the problem IMO.

I'm surprised you make such a comment my flower.

Has the basket the same part number as the original. I think earlier clutches had more plates. I assume you have slack in the cable ?

It's in the post, addressed Breagh, Fife. I'm sure it will get to you soon. Happy Birthday.

If you have swapped everything else, and ruled out the loom ....

Has the generator been on another bike ?

Boring to watch, or boring to ride ?

New plug first.

Was the original sprocket dished ?

Breagh must be at least 65, possibly more.

And if your going to swap, at least use one the same make/colour.

Pete, do you feel the 4rt has improved your results ?

https://www.cromwell.co.uk/shop/spindle-nose-and-workholding/fixing-components/fc06-m10-milled-t-slot-nut/p/IND4252035G?utm_campaign=pla+-+&utm_source=google&utm_medium=shopping-pla&utm_keyword=IND4252035G&istCompanyId=6aa6787b-063e-4414-802d-129f235df603&istItemId=aqrxrtlpw&istBid=tztt

I'll bet 90% are carrying alot more than 6kgs around ...

Well written piece, I felt like I was there. The only bit that spoilt your narative was I2.5 stone ........