how much for me to just mail my engine to you?
Hey, thanks for describing the procedure. When I put my engine together after lapping the heads, I noticed the timing marks on the crank and cams were slightly off. It looked like chain stretch has retarded valve timing (as in: the crank runs +/- 1 degree ahead of the cam shafts). I can't tell the real-life influence on engine power....however it does feel a bit gutless under 4000tpm, even with correct valve clearance, adjusted and synced carbs, airbox mod, new plugs etc etc. I kinda got the hang of this whole engine tweaking business since lapping the heads, so I'm definitely considering degreeing the cams and redoing the valve seats in time. I actually regret being in such a hurry to get it going again.FOG said:Because of the difficulty in determining the exact point of the valve opening we use “Lobe Centers” To convert the chart above to lobe centers Do: 65-45+180/2=100 . 100 degrees lobe center for the intake cam
70-40=180/2= 105 Lobe center for the exhaust cam.
Ok if you did all that above and you got something different, here’s how you fix it.
Remove the cams and remove the sprockets from the cams. Elongate the Bolt holes about 1/8 “ in each direction. Replace the sprockets with the bolts located in the center of the elongation.
FOG, thanks, now I understand the whole process. But how to accurately elongate holes in the sprocket? Did you used some sort of vise or did you just do it by feeling? I am afraid that by doing it just by hand (by feeling) accuracy wont be high enough.FOG said:The sprockets are bolted to the cams at two places the hole in the sprockets must be elongated to allow the cams to be shifted withing the sprockets. about 1/16 each way is enough. you can do this with a dremel.