Debated a lot about 300 vs 331, OEM vs Bill Blue and in the end I went OEM 300cc for a ton of reasons. Job was actually very easy, I worked on it from 8:30 AM to 11:30 AM on Saturday and then from 8:30 AM to 11:00 AM on Sunday. Done.

Still need to clean up and put the seat/plastics on, but the bike fired right up and ran perfect. No test rides yet thanks to snow, but I will get it out this weekend.

My only mistake was with the t-stat, I didn't put it back in correctly so it leaked. Had to drain the #%$#^ coolant, take off the housing, spin the t-stat around and put it back together. Added, 15 minutes to the job.

Anyway, thanks to all who were the first to do this, it was comforting knowing it was a straight forward bolt on. Looking forward to my new found power.

 

sweet!!!! congrads

 

Cool, you'll love it! I didn't remove my t-stat when I upgraded tho... Why'd you do that?
I just removed the rads entirely and left the t-stat alone.

 

The t-stat is in the head, no? So at the least you need to remove the hose and housing. I took it out so it wouldn't get damaged; never thought about it having a specific way to put back (other than a front and back) so I just stuck it back in. Wasn't until I removed it to check for damage that I noticed in the service manual it has a specific orientation. Lesson learned, and no real harm done.

BTW, I didn't remove my rads, why did you do that?

 

lol, to each his own I guess... I thought the t-stat is threaded into the bottom of the rad? With a single wire coming out of it?

 

No, that is the temp sensor. The t-stat is in the head, if you follow the bottom rad hose to the head on the right side of the bike you will see the housing held by three bolts, it is in there.

 

What is the right way? I did not pay any particular attention when I did it other than making sure the same sidethat faced out before faced out after. I do not think I worried about whow it is rotated? How do you know it was wrong?Mine seemsnormal&I have 700+ miles on it since.

 

There is a little hole in the metal ring just next to the rubber outside ring, they called it the bleeder hole and made a point to say "it must point toward the back of the engine"

I have no idea which way mine was pointed, just that I was weeping coolant very slowly from the housing and tightening the bolts didn't solve it. Took off the housing, put the t-stat back in per the manual and torqued the bolts back down to the spec (87 inch pounds IIRC), no more leaks.

So if it isn't leaking don't worry about it. My guess is that the way I put the stat in held the housing from sitting 100% flush, I had the stat br running front to back, when I corrected it, the bar at the top of the stat run up and down, that must have been the issue.

 

Marc how did you get the part numbers, did you just go to a OEM lookup and buy what you needed?

I'll probably do this mod this summer, thanks for any help and reports.

 

so what were the reasons for not getting the bigger bore? did you get a new carb?