HI, i am a competitor in the british national hovercraft championships and my perticular class requires that i run an (up to) 500 cc 2 stroke air cooled thrust engine. It appears that the way to go will possibly be the KH500 H1 Triple with ported heads and some expansion chambers to get the powerband where i want it (at about 6500-7500 rpm).
Firstly, do you agree that this engine is the right move?
Secondly, Anyone know where there might be one for sale?
All advise appreciated.

I think it would be easier finding hen's teeth! Also it would be an expensive engine to maintain, three of everything etc
Is there nothing more recent you can use? the only real benifit i can see is a smooth power delivery with the KH motor

I would of thought the RD400 yamaha engine a better choice and probably easier to find/fix

You see, thats the issue. Because i have to go air cooled, they are all old motors. Your not the first to suggest the RD400, which might be more tweakable as (from what little ive gathered) more people know what to do, and how to do it to get more power from the standard form.
Thanks for your input.

in the late 70's and early 80's there was loads of tuned 400's racing in my local area ie Croft .. can't recall ever seeing a KH in any shape or form racing.. i would of noticed, i owned a KH250 at the time ;)
But by all accounts the RD parts are still fairly easy to get.. i think you can do some mixing up with more modern parts too

If i can track one of my friends down I'll see if he was any RD engines.. he did a few years ago