E: Engine Comet elect coil ignition make and timing?

Don Morris

Active Forum User
VOC Member
Thorspark have told me that static timing is not reliable and that strobing is the only way. Which is a nuisance when fitting to a bike that is all built up. I have used an expanding rod, with timing disc, in place of the big end feed bolt, for static timing, but would not use it with engine running.
I am currently trying to set up my bike with Thorspark and find the absence of any precise way of lining up the mag to the engine a nuisance, to say the least. It has taken me several attempts so far, all using the strobe.
 

Bill Thomas

Well Known and Active Forum User
VOC Member
Can't you put a mark on the cam and a mark on the body edge,
By static, Then check with scope,
I am sure we did a few years ago,
I remember seeing the advance working ?.
Cheers Bill.
 

Martyn Goodwin

Well Known and Active Forum User
Non-VOC Member
No photos but ...... You can run the Comet motor with the drive case cover removed with no oiling issues and It is possible to mount a timing disk on that side using the internal thread on the ESA retaining top hat nut. The only 'struggle' will be locating a bolt of the correct size for the thread, which as I recall is 3/4" x 20 tpi, to clamp the disk to the ESA.

Hint: you could use a discarded mainshaft to knock up a fitting to clamp the disk.
 
Last edited:

Don Morris

Active Forum User
VOC Member
Martyn is right, the thread is 3/4" x 20 tpi, which is a Whitworth thread, "Special". I use an E80, hollow axle nut, to clamp the timing disc. The bolt is a plain piece of rod which was part threaded by a friend, this was many years ago. The Thorspark has no contact breaker, you are forced to use any marks to guide you, from the supplier these are felt pen marks, and then check with a strobe.

Thinking forward if I satisfactory time up OK I will mark up the rotor and mag housing this and my piston stop, a plug type body with a fixed rod sticking out which hits the piston (carefully) at the desired timing point.. Useful if your timing slips while you are out on the road, and setting up the timing disc at home. I have manual advance and retard by the way,

I look back, with some nostalgia, to the fag paper.
 
Top