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I am having some problems determining if my cams are properly set up and could use some help from those who have done this before. I have gotten zero info back from the cam manufacturer.
I just rebuilt the motor on my 1976 T140V and put in a new set of Megacycle 51005 cams that call for degreeing-in. Specs as follows:
Intake to open at 41 BTC and close at 61 ABC and lobe center at 100 degrees.
Exhaust between 63 BBC and 39 ATC and center at 102 degrees. Both have 282 degrees duration and call for .010 valve lash.
Both cams were set to the factory timing marks and were not degreed-in. However several people said that I should degree-in so as to gain full benefit of these cams which offer more oomph at lower revs than the standard cams. They also commented about possible damage etc. I did run the bike and it seemed to run fine. Because I am babying it to break it in, I am unable to comment whether or not I have made any real performance gains.
Anyway I tore things apart again and used a timing wheel and a dial indicator on the rockers. I know, I should set the dial indicator on the cams themselves but I am getting a bit tired of all the on and off again and figured that while accuracy may suffer, the results should be the same. According to my setup, I am dead on in the valve timing using the the opening and closing specs. However the lobe centers which I understand should be the maximum point of lift are both out. The intake maximum lift is about 10 degrees too late at about 90 BTDC and the exhaust is about 10 degrees too early at about 90 ATDC.
I should mention that I also installed a set of mushroom tappet adjusters but I don't believe should affect timing wise. I am retaining the standard radius cam followers.
I am not sure how to proceed at this point
I just rebuilt the motor on my 1976 T140V and put in a new set of Megacycle 51005 cams that call for degreeing-in. Specs as follows:
Intake to open at 41 BTC and close at 61 ABC and lobe center at 100 degrees.
Exhaust between 63 BBC and 39 ATC and center at 102 degrees. Both have 282 degrees duration and call for .010 valve lash.
Both cams were set to the factory timing marks and were not degreed-in. However several people said that I should degree-in so as to gain full benefit of these cams which offer more oomph at lower revs than the standard cams. They also commented about possible damage etc. I did run the bike and it seemed to run fine. Because I am babying it to break it in, I am unable to comment whether or not I have made any real performance gains.
Anyway I tore things apart again and used a timing wheel and a dial indicator on the rockers. I know, I should set the dial indicator on the cams themselves but I am getting a bit tired of all the on and off again and figured that while accuracy may suffer, the results should be the same. According to my setup, I am dead on in the valve timing using the the opening and closing specs. However the lobe centers which I understand should be the maximum point of lift are both out. The intake maximum lift is about 10 degrees too late at about 90 BTDC and the exhaust is about 10 degrees too early at about 90 ATDC.
I should mention that I also installed a set of mushroom tappet adjusters but I don't believe should affect timing wise. I am retaining the standard radius cam followers.
I am not sure how to proceed at this point