@alainm, I think the only thing needed to convert a 600RS race sled (based on the 600 HO carb) to trail was to change to the ignition timing by disconnecting the hot start button. It was never said, but I
suspect this was changing the ignition timing to the one used for break-in. I had asked, but I didn't get a straight answer. I would have needed to press the question and have it forwarded to the gentlemen who at the time was responsible for changing the ignition timing maps on a whole slew of sleds including the 380 fanner.
For the base gasket which determines the squish, this is something easy enough for anyone to check. If one finds the measurement to be iffy, then the answer is in measuring piston projection. There is enough about this subject on DooTalk to keep one busy measuring and thinking. The thing is, there is no free lunch. I have since learned though trial&error that there was room to bump the power for trail riding, but I remained within a tolerance that I was comfortable with.
I thought that I reached a tight squish until I found a gentlemen on DooTalk who had inadvertently rebuilt his 800RE engine with such a tight squish that the engine survived one of the pistons kissing the head. The piston projection was posted on DooTalk, which I considered the holy grail on squish. I see it a little more complex than a simple measurement, but the level of information was ahead of anything I could dream of getting from the racing community. It also gave me an idea for the capability of the trail 800RE.
I am all for bumping the engine power, but within reason and with some knowledge to go with it. Are you planning on going to the
Napierville Vintage show ? I have been toying with the idea of making an appearance with a 1000 SDI, but I would feel more comfortable with someone with your experience.