The BSA A7-A10 Forum

Technical => Lucas, Electrical, Ignition => Topic started by: Johnny J on 09.06. 2015 16:55

Title: Timing changed by itself?
Post by: Johnny J on 09.06. 2015 16:55
My bike has been quite easy to start and has run good, but after a longer trip (300km) last weekend it doesn't any more.
Now it kicks back quite severly, takes more kicks to start and pings alot.

Guess I have automatic timing, (GF 1960) what could have happened?
Can it change to more advanced timing by itself?
What else could have influenced this?
Title: Re: Timing changed by itself?
Post by: bsa-bill on 09.06. 2015 17:00
Possibly stuck open (in advance), broken spring or springs, or fibre drive gear has stripped a cog or two and it's moved the timing
Title: Re: Timing changed by itself?
Post by: orabanda on 09.06. 2015 17:05
I had a similar experience; the lock nut on the points loosened, and the points gap had increased - check points gap is 0.012" - 0.013"

Richard
Title: Re: Timing changed by itself?
Post by: Greybeard on 09.06. 2015 17:50
I had a similar experience; the lock nut on the points loosened, and the points gap had increased - check points gap is 0.012" - 0.013"

That's my guess also.
Title: Re: Timing changed by itself?
Post by: Johnny J on 09.06. 2015 20:20
OK, thank's guys, will check this as soon as my back pain has eased of a bit.  *lol*
Title: Re: Timing changed by itself?
Post by: morris on 09.06. 2015 21:26
OK, thank's guys, will check this as soon as my back pain has eased of a bit.  *lol*

Don't tell me the kick has hit you in the back...??  *conf2* *countdown*
Title: Re: Timing changed by itself?
Post by: Johnny J on 09.06. 2015 22:42
Yeah, I was sitting on the footpeg and leaning back rapidly to start it. ;-)

No I have had this back problem for some time now, sucks...
Title: Re: Timing changed by itself?
Post by: Johnny J on 28.06. 2015 18:22
Anyone familiar with how to adjust these points?
Title: Re: Timing changed by itself?
Post by: Greybeard on 28.06. 2015 18:32
Loosen the screw and the baseplate can be moved allowing the points gap to be set.
Title: Re: Timing changed by itself?
Post by: Johnny J on 28.06. 2015 19:13
Thanks!

Is it normal that you can turn the plate (or is it the whole inner of the magneto) by hand a few degrees left and right or should it be totally rigid?
Title: Re: Timing changed by itself?
Post by: Greybeard on 28.06. 2015 19:20
If you have an automatic advance and retard unit the magneto shaft will move a few degrees as the weights are forced out. The points base-plate must not move in relation to the magneto shaft.
Title: Re: Timing changed by itself?
Post by: Johnny J on 28.06. 2015 20:00
Seems like adjusting the points did the trick, it started on the first kick!
The point were too close, took them to 0.012".
Title: Re: Timing changed by itself?
Post by: Greybeard on 28.06. 2015 20:24
Remember that the points gap affects ignition timing: Too close and the timing will be late, (retarded). Too wide and the spark will be early, (advanced)
Title: Re: Timing changed by itself?
Post by: Johnny J on 28.06. 2015 21:23
Yes, I will see how it runs in a couple of days, especially when warm.
Have to stuff myself with pain killers first...  *conf*
Title: Re: Timing changed by itself?
Post by: Triton Thrasher on 28.06. 2015 22:27
There's a little oil wick in the cam ring.

Some light machine oil on it might slow the wear down.
Title: Re: Timing changed by itself?
Post by: cyclobutch on 29.06. 2015 13:48
I expected this to be too advanced - "kicks back". But the suggestion here is too retarded? (and yes unfortunate comments duly invited).