I'm putting on a new 300 barrel tomorrow, but would like to know if the 300 kit uses the two collars to help locate the barrel onto the cases? I hope not as predictably I've a trackday on Monday and don't have any with which to do the rebuild.

I noticed from Tyga's website the kit does appear to have the collars, but I don' t remember them being there when I took the barrel off a few weeks ago. Saying that, as most of you know my memory isn't the sharpest tool in the box. Andy, did you ever install them?

I could wrestle some old ones outta a spare 250 barrel I have, but I suspect the OEM 250 ones will need to be shortened to match the machined 300 barrels. Is this the case Matt?

My 300 has them and every two stroke I ever remember working on has had them. You don't want to screw up all that time on the grinder by misaligning everything. I think the 300 uses the 250 dowels. If I remember correctly the 300 cylinders were machined out to accept them.
_________________
1995 A kit TZ 250
1994 Rothmans NSR 300sp SOLD
1998 RM 250 freestyle/motorcross
1998 Meathanol burning CR 500 AF super retard/motorcross/sand dunes/play bike

Tom, already sent you a mail.

To all others, Jeremy's correct in that the 300 uses 2x dowels in each cylinder for location, just like the stock 250 cylinders. They are the standard part.

Oh Jeremy, you've obviously never worked on a Honda NZ110 air cooled thingy. Hmmm. M8 studs and 9mm holes in the cylinder make for interesting rebuilding. The difference between fitting it right and just fitting it was about 2hp. We fitted dowels to the race bike!