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I'm in the final stages of my first B44 rebuild and am getting confused about the ignition timing procedure. I've set the points gap (the cam on the auto advance unit has a mark for peak position) but have received differing opinions for setting the timing. Some say position the piston at 1/16th inch before TDC on compression and then rotate the cam until the points just open and then lock down the auto advance. This is suppose to work until the timing can be strobed. Others say use the mark on the alternator rotor (full advance position?) and then with the points plate turned full clockwise turn the cam until the points just open and then lock down. What is your experience? Are they both the same, just going at it differently?
Thanks All
Jim

Hi JJ, This is the process I use so hope it's some use to you. I am not a mechanic's arse so if I use the wrong term please forgive and I will try to explain further if needed.
1. Remove spark plug and tappet covers.
2. Put bike in a high gear and rotate rear wheel with something down plug hole (that wont snap if caught - drinking straw perhaps). You are after the the point where the piston is at TDC with the valves closed.
3. When you have that point look at your alternator. Rotate the wheel back until the mark on the alternator is past the needle on the cover. Then move the wheel forward (in direction of travel) until point lines up... you must be going forward to eliminate backlash - dont go backwards to make the points line up.
4. When the points on the alternator line up you are, I believe, at 28 degrees BTDC.
5. Be careful not to move anything. GO to your points...
6. Either fix the advanced unit in the fully advanced position (this can be done with a washer) or ensure that the points open when the auto unit is moved to the fully advanced position.
7. You want the points to just begin to open when the auto advance reaches the full advance position. I use a 12v battery connected to a beeper to do this (if you like I can send you a pic)
8. This should get you going. I have experimented with using a strobe but not having a rev counter it is a game to work out where 3000 rpm is and although I have had the bike running better it was a pig to start so went back to static timing. My bike starts first or second kick using the above.

If you are confused by this I asked for advice on the same a while ago and had an outstanding reply from RF Whatley.. you can probably find it if you look. Let me know if you need more help and good luck.

JJ,
Either method is OK... If you are pretty sure the timing mark is ok, use that procedure. If you don't know use the other procedure except that the 1/16th inch BTDC should be about .30" BTC...or a fat 1/4 inch will be close enough for starters. Once running verify with a strobe that bike runs well (no pinging) and starts well on the timing mark when timed to the timing mark. If the timing mark is off, make a new one for future reference where it runs best.

Mr Mike

Thanks Guys
I presume that the points plate should be positioned in the middle of its adjustment.
Jim

Jim -
See my tech article on GABMA named "Timing BSA Singles". It covers all the pit falls of doing this.

:bigt: