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XLFREAK
10th July 2005, 01:19
1962 xlch mikuni WITH accelerator pump
i opened up the lid to the magneto and i adjusted the points gap to spec (.015) now it wont start at all. ill get a few good kicks, and then it just kicks through without hardly any resistance about 9 or 10 times and than im back on a few good kicks. i kick through and it blows the carb off of the rubber manifold. i have kept the air cleaner off ( just to make sure there is gas)so there is nothing holding the carb on except the hose clamp. i put it back on and it goes through the same cycle. i just dont understand enough about this to have a clue to whats going on. anyone know?

dabronco
10th July 2005, 01:44
Check your timing. You're getting spark when an intake valve is still open.
Points gap affects timing. Opening them advances the timing, closing them retards it. When you set the points, which way did you go?

XLFREAK
10th July 2005, 03:49
i opened them

flathead45
10th July 2005, 04:12
yep , your timing is advanced too far

those mik's are a difficult bird to keep on as is and if your spittin back through the intake your gonna lose it now and then

AeroSport
10th July 2005, 07:55
On my old 69 XLCH I was alwasy able to gap the points in the Mag with a matchbook cover. It was the perfect size. But if my memory serves me right I thought it was .020. Could be wrong though that bike hasn't been around since 1980

vivisix
10th July 2005, 20:13
interesting that I just had this happen to me last night, but it seemed to be running fine. Damn carb just blew off the bike with a backfire. Must check timing.

blueglide88
10th July 2005, 21:45
Sorry to hear about your carb, but it reminds me of one of the funniest damn things I ever saw. It was back in the early '80's, and my buddy and I were riding to Sturgis. We decided to get off the Interstate and take a secondary highway for awhile. As we were riding, we came upon a country road intersection with a VERY good looking girl standing next to a few bikes looking very bored. We quickly pulled over, and noticed all the guys were in a corn field. I asked what was going on. She said she was hitchhiking to Sturgis, and these guys had picked her up only a few miles earlier, when one of the bikes had backfired, shooting the carburetor off the bike and into the corn field! How it came off the throttle cable I don't know, but I laughed my ass off seeing these guys walking thru the corn looking for a carb. I asked if she wanted to ride with us instead, and told her our bikes would not leave her stranded. She kinda wanted to, and with some persuasion probably would have, but one of the guys had came over to see what was going on between her and I. My buddy and I did not stick around to argue over her and left. I must have laughed for the next 30 minutes at that sight. :D

XLFREAK
11th July 2005, 00:59
do any of you know anything about the mags that were stock on the early sportsters? the one on my bike is "fixed position" i odnt see any kind of advancement inside the mag.. how does it advance timing when the rpm's go up? the cover of the mag says "TCME>>>>" any information would be awesome

nite53
30th April 2006, 06:33
do any of you know anything about the mags that were stock on the early sportsters? the one on my bike is "fixed position" i odnt see any kind of advancement inside the mag.. how does it advance timing when the rpm's go up? the cover of the mag says "TCME>>>>" any information would be awesome

My '64 XLCH I just bought has the same initials, TCME on the Mag cover. Which make is this mag??? I just bought a condenser for it today, a Morris brand I think?? Is that the right condenser?
Thanks

72 Ironhead XLH
30th April 2006, 15:46
That way it works :the mag was originally connected to the left hand grip the you moved away to retard and toward you to advance once running.just like the throttle.if that system was removed(change bars)the base of the mag was tightened a bit and a spring was added to pull the mag to full advance and keep it from retarding. to start you moved the mag to retard and kicked.once running you moved the mag to advance.as far as the gap is concerned it will vary between .012 and .020 .whatever works best for your particular engine is what works.once you find the gap your motor likes ,to set the timing : set flywheel timing mark,use cigarette paper between the points, advance the mag untill the paper can just be pulled out.andjust the mag stop at this point. retard to start (push the mag to retard position)

geraldxlch
2nd May 2006, 04:12
pre 63 sportster magnetos were the fixed type, yours may be set up like this. Tighten it down at the happy medium. This is retarded enough to start it but advanced enough to not burn your valves when running. You'll know when it is too far advanced to start, it'll kick back like a mule. Use the notch in the mounting base plate for reference when adjusting. Move just a sixteenth at a time. Back of the mag (spark plug end) toward motor is advancing the spark.