Ok, so earlier this year I finally finished my build. Its a stock internals 80' that I added the following to- HHB PMA, PAMCO and new VM34's from Hoos racing. Bike was running great and I had a few fun rides on it. Since I didn't touch any of the internals it had a generous oil leak, that kept getting worse(go figure). So i bought a gasket kit, took the motor out and replaced the offending gaskets, mainly the jug to case gasket, although the head gasket was leaking as well. After this, I reassembled and went for a ride, bike was soft down low, then would pull like a bat outta hell. After some research on here, I determined the cam was slightly retarded. Took it apart again, reassembled(possibly hastily), then would try and brake your ankle while kicking. Too far advanced. Again w/ the diss-reassemble. Now, it will start first kick, barely run and won't take any throttle. I have messed w/ the timing to no avail. I did make sure that I was at TDC and the cam lined up perfectly. The notch was straight up, and the dimple was perfectly level w/ head. I used a dial indicator and a timing wheel. Before I rip this thing apart again, just looking to see if there was something i missed. Thanks in advance for any help
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LITTLE HELP OVER HERE PLZ
- Thread starter tbird
- Start date
how did you manage to get the cam out of alignment ?
if the pistons are at TDC and the cam has the notch facing vertically at 12 oclock....... the chain and static timing have to be correct ...have you checked the timing with a strobe ?
that is what I am assuming as well, I was hoping a different set of "eyes/brains" would find something I missed. Even when the bike was running good, I never could get a timing light to work, so unfortunately I have not checked timing w/ a light. And I have tried 2 different lights.
I'm not sure how successful a strobe would be as I have not used one on mine yet . I was lucky with my engine build it just started right up and ran perfectly with a Boyer Bransden ignition system although I had a stuggle to get the carbs dialled in.
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I was lucky too, it ran great, (prob could have used a little more carb tuning) until I took it all apart. I just can't see what could have changed(timing, carb, etc) during the reassembly. I might have to tear it down once again, just trying to avoid that since I've had it in and out so many damn times
re-reading your initial post I wonder if the reason you had an unresponsive throttle pick up was actually nothing to do with the timing but more likely the carbs .
I suspect that the cam chain might now be set incorrectly putting your static timing out. That could account for the kickback.
I'd double check that the camshaft has the notch in the vertical position with the pistons at TDC. Check the pistons through the spark plug holes rather than rely on the TDC rotor marks .
I suspect that the cam chain might now be set incorrectly putting your static timing out. That could account for the kickback.
I'd double check that the camshaft has the notch in the vertical position with the pistons at TDC. Check the pistons through the spark plug holes rather than rely on the TDC rotor marks .
Because the camshaft rotates at 1/2 crankshaft speed, an alignment error of 1 tooth on the 36-tooth sprocket will cause an error of 20* at the crank. This is not a subtle difference.
Re. ignition timing. Since 1965 I have owned and ridden motorcycles by Suzuki, Honda, Yamaha, Kawasaki, BMW, Bultaco, Triumph, and Harley-Davidson, in displacements ranging from 50 cc. to 55 ci. Some had breaker point ignition, some had OE electronic ignition, some had aftermarket electronic ignition, including Boyer. Every one of them produced a readable flash on a strobe timing light. Tbird, if you haven't checked ignition timing accurately with a strobe, you're thrashing around in the dark.
Re. ignition timing. Since 1965 I have owned and ridden motorcycles by Suzuki, Honda, Yamaha, Kawasaki, BMW, Bultaco, Triumph, and Harley-Davidson, in displacements ranging from 50 cc. to 55 ci. Some had breaker point ignition, some had OE electronic ignition, some had aftermarket electronic ignition, including Boyer. Every one of them produced a readable flash on a strobe timing light. Tbird, if you haven't checked ignition timing accurately with a strobe, you're thrashing around in the dark.
Timing light with clip on plug wire probe; retry with probe upside down (plug wire in opposite direction). a common timing light doesn't work issue.
What ignition?
If you still have the stock mechanical advance, rod, bob weights etc. I'd be looking into smooth correct action or lack thereof.
What ignition?
If you still have the stock mechanical advance, rod, bob weights etc. I'd be looking into smooth correct action or lack thereof.
Has the Pamco been static timed.......Removing and playing with the cam means the pamco has been taken out and reinstalled as well...........
thank you all for all the help, I unfortunately did not have a chance to look into it this past weekend. When I get a chance, I am going to start by double checking the static timing of the Pamco, then go from there. I am pretty sure my cam timing is spot on. Once again thank you all, the different set of "eyes" really helped me out.
