I went back to a more conservative jetting setting and within 5-6 kicks. I took a short video for Julian to show him that the bike was actually running and to demonstrate the popping that I told him the bike was experiencing. When I reviewed the clip, I noticed that some of the popping was coming from the head gasket, that puffs of smoke were coming out when it popped! I suspected that maybe the head bolts needed a little tightening. Indeed they did!
I checked the bolts and some were so loose that I could unscrew them by my finger strength! I guess it's my fault that I didn't think of this earlier, since the motor was freshly built. But I would have thought that Paul should have told me that after heat cycling the motor a number of times, I should tighten up the head bolts!! Details, Paul!
I tightened the bolts to 17 ft/lbs. in a criss-cross pattern across the entire head, since it's a one-piece head. Amazingly afterwards, the bike started on 2 kicks! And that's when the engine was dead cold from a sit overnight!! I heat cycled and cooled the engine 4 or 5 times and retorqued the bolts over and over again. Funny thing- the popping went away!! as well as the puffs of smoke!
So the loose head could explain a bunch of things going wrong. First of all, the engine wasn't getting good compression, which would make it hard to start the bike. Also it made it harder to reach the top end, running out of power. Secondly, the fuel ratio in the combustion chamber was more lean, because every time the piston moved downward to do a filling cycle, it would be pulling in additional air through the head gasket leak! So suddenly my A/F mixture was all off and all the testing I did has to be done all over again!
After a little testing, I calculated that I would be able to move down to a smaller pilot again. So I popped in the 30 pilots and I put in smaller mains, moving to 250's. I took the bike out on a run and it ran nicely on the low end. (I still have to work on the mid-range.) I took her down Isabel and yanked on the throttle WOT. The bike actually pulled up to 8500 rpm, that's the redline!! It probably could have gone into the red, but I didn't want to hurt the motor just yet. Just after that, the bike died, running on one cylinder. At first I thought that maybe I seized the engine, but after testing I believe that I just fouled one of the plugs. I looked at both the plugs and they were a pretty nice tan. I think maybe one of those old spark plugs just gave out. I'll pop some newer ones in and do more testing tomorrow.
I checked the bolts and some were so loose that I could unscrew them by my finger strength! I guess it's my fault that I didn't think of this earlier, since the motor was freshly built. But I would have thought that Paul should have told me that after heat cycling the motor a number of times, I should tighten up the head bolts!! Details, Paul!
I tightened the bolts to 17 ft/lbs. in a criss-cross pattern across the entire head, since it's a one-piece head. Amazingly afterwards, the bike started on 2 kicks! And that's when the engine was dead cold from a sit overnight!! I heat cycled and cooled the engine 4 or 5 times and retorqued the bolts over and over again. Funny thing- the popping went away!! as well as the puffs of smoke!
So the loose head could explain a bunch of things going wrong. First of all, the engine wasn't getting good compression, which would make it hard to start the bike. Also it made it harder to reach the top end, running out of power. Secondly, the fuel ratio in the combustion chamber was more lean, because every time the piston moved downward to do a filling cycle, it would be pulling in additional air through the head gasket leak! So suddenly my A/F mixture was all off and all the testing I did has to be done all over again!
After a little testing, I calculated that I would be able to move down to a smaller pilot again. So I popped in the 30 pilots and I put in smaller mains, moving to 250's. I took the bike out on a run and it ran nicely on the low end. (I still have to work on the mid-range.) I took her down Isabel and yanked on the throttle WOT. The bike actually pulled up to 8500 rpm, that's the redline!! It probably could have gone into the red, but I didn't want to hurt the motor just yet. Just after that, the bike died, running on one cylinder. At first I thought that maybe I seized the engine, but after testing I believe that I just fouled one of the plugs. I looked at both the plugs and they were a pretty nice tan. I think maybe one of those old spark plugs just gave out. I'll pop some newer ones in and do more testing tomorrow.
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