To answer; I'm not really sure which pipe this is. Can you tell from one of the pictures from page 3/4? Do you have pictures of the few you mentioned? There are no markings/numbers on the expansion/silencer anywhere.
So the good and bad from the past two days. (mostly good).
The good was, this machine ran fantastic all day! No major issues to speak of. Got tons of compliments on it. This thing really SCREAMS from 1/2 to full throttle. At the 1/8th mile I won some and lost some. I'd say anything sport with over 250cc was able to beat me; but I beat a KTM200, a WR250, and came close every other racer. This machine is fast. REALLY FAST. Much faster than I had imagined it would be.
I put about 4-5 hours on it and burned 10 gallons of C12
DurhamTown is a fantastic place. We camped out and had 2 full days of riding.
Now for the bad... I think the head gasket may actually be leaking but I'll run some tests to be sure. While the radiator was cold this morning I popped the cap to just take a look - and I noticed a non-stop stream of bubbling while the
Engine was cold and idling. I was very sad to see this; but I DID re-use the old head OE head gasket without anything to help it hold. I did not shave the cylinder nor the head either - but I did of course clean them up very well on assembly. The gasket was new looking and I didn't have a new replacement and so I used it. Bummer. After seeing the bubbles I checked compression and it was still 180 so its either not a significant leak or its leaking air bubbles in from somewhere else - Hope not. The Engine is not ingesting coolant from what I can tell. I will be draining the balancer oil to be sure no coolant got in there. Its 50/50 Prestone/Distilled. Retirqued tge Head but the nuts didn’t move and no help. None-the-less I ran it for the entire day even with the bubbling as there was little I was able to do to fix it at the place. I did not check it more than once either because the machine was hot all day. I plan on installing an Autometer water temp gauge before the next ride. I also plan to run some vacuum testing on the cooling system to see if it will hold vacuum or not. I was planning to remove the head after today's rides anyway to check health of the piston/walls anyways, and so I'll probably just go ahead and order a new copper head gasket.
The only other issue I had was with one of the axle CV boots. Seems the one on the clutch side's clamp wasn't tight enough, and so about 2 tablespoons of grease spun out. Some of it probably slipped the belt/clutches but I didn't notice. No biggie.
Jetting. I need to do some research on brand conversion. I ended up with 48/1370(Middle)/152 jets, but the 152 jet was not a keihin - it was an EBC. See, Durhamtown has lots of jets in their pro-shop, but there are all EBC brand. Since I knew I needed to tun this thing and didn't have what I needed, I decided to run what Durhamtown sells; and BTW they DO let you trade-up your purchased jets with another size if the first size you buy isn't right - so I gave it a go and I'm glad I did. I'm not positive of the conversion but what I can say is, the machine ran GREAT with a 152
EBC main, but then noticeably worse with a 155
Keihin main. I did not have a chance to try a 155 EBC main but I did get one before I left to try and compare with the 155 Keihin another time. EGT was never more than 1100F, and the probe is like 5" from the piston. So basically I may try the 155 EBC that is IF I still have this PE carb on here. I did source a PWK39 which I plan to install with dual stage pre/post air filters with a modified airbox lid soon - which means jetting will have to be re-done from base-line then.
RPM. This one kind of stumps me. No matter what I did, my tiny tach always showed the same PEAK rpm of 7200. I wasn't watching the tach all the time - barely ever - but it does show me peak RPM of the session on Engine shut off - 7200 EXACTLY. Not +/-10 or anything. Always exactly 7200. I'm almost thinking either the rev limited modification I did didn't work, or just perhaps the PowerBlock needs a couple of weights removed. Any help here is appreciated.