Forum

[Martin (Sale Mcr)]

After trying to guess what 0.8mm / 1/32", is for years, I decided to buy a deg. wheel kit from our Host. Got the piston to TDC & the deg. wheel set to 0 deg. Then the question was how many deg. should it fire BFTDC ? The workshop manual only shows everything as 0.8mm / 1/32".
Please may I ask if someone could tell me how many deg. BFTDC should the points open? for static timing.
And also how many degs, should the auto advance bring in, when checking with a strobe light/ Thank you in advance Martin

[papasmurf]

What model of Enfield would help.
Otherwise technical help here:-

http://www.hitchcocksmotorcycles.com/technical-notes

[ric]

Assuming your stroke is 90mm then you want 32 degrees BTDC at full advance when using the strobe to achieve the recommended static figure in the book.
But with modern petrol 34 degrees will give better results.
The hardest part will be accurately finding TDC for this you'll need a dial gauge or a positive stop to (gently) run up against and back against. This is because piston movement at TDC is almost imperceptible. If your near Bristol I can lend you a dial gauge.

[Martin (Sale Mcr)]

Sorry guys A senor moment again, It is a '89 350 bullet. I have set up up using a DTI. but did not think about the technical notes on here. It shows 10 deg. My thanks to all.

[Nettshubby]

If using a dti to measure 0.8mm btdc, it must be vertical, ie, in line with the cylinder. If it is just screwed into the plug hole at an angle it doesn't measure true vertical movement of the piston.

[ric]

Oddly enough with such a long stroke it doesn't make enough of a difference to worry about



http://tinytim.forumcircle.com/viewtopi ... ght=timing

[PeteF]

Degree disks and dial gauges to time a 350 Bullet?
Way over the top IMO, just get it near enough then tweak it till it's right.

[Chris [Stockport]]

Hi Martin, I must remember to talk to you about timing (a slightly different issue of my own). I'll try to remember when I see you, hopefully at Astley green on the open day/rally.

atb, -C

[simon]

Im with Pete
6.5:1 compression is not going to make the motor that fussy. However I think the big issue is setting the timing statically at the retarded position. My 350 gets set at 1/2" btdc with the bob weights in the advanced position (although with a mag the bob weights are easy to access). If you are going to use a timing wheel then i would also get a light and get the position correct at running speed. Ive just being messing with a BSA B44 which is a prick of a thing to time statically but a relative breeze with a light.

[Tim NZ]

The AA unit has 11 degs of advance range, which is 22 deg crankshaft.


Timing is nominally noted as 32 degrees.


Thus, static timing is a nominal 10 deg BTDC