AJS & Matchless Owners Club

I am still having fun and games trying to sort the ignition on my rebuilt G80. The timing has been set to 1/8" btdc using a light bulb - several times! but the result is the same - a kick back. there is no valve lifter fitted at the moment but I don't believe that to be the problem as, having kicked back, if the kick start is just touched to start to turn the engine, there seems to be an attempt by the engine to fire which can be felt. Also,. yesteday I turned on the ignition, and as I switched it on there was a soft "pouff!" as the engine tried to fire! A new wiring harness complete with new switches has been fitted - made to order as per Jampot ad - and I have fitted new points and coil ... but not condenser, could it be that? I have also changed the auto A/R retard unit. Has anyone a 'magic wand' I can wave to cure this? I have even considered fitting a mag! Please, your advice/ideas.

I'd fit a valve lifter (before a broken ankle sets in!) Also have you tried setting on full advance with the AR wedged open?
Dave.

"I have fitted new points" - may be worth checking that the isolating washers are in the correct position.
Sean

waiting for a valve lifter spring to arrive - new one I bought doesn;t work - I haven't tried setting on full advance yet, was going to try setting at tdc

re isolation washers - if they were wrongly fitted wouldn't it just short out

AyJayBee wrote:re isolation washers - if they were wrongly fitted wouldn't it just short out

Correct - and it wouldn't fire

AyJayBee wrote:waiting for a valve lifter spring to arrive - new one I bought doesn;t work

Really? all it does is hold the lifter away from the rocker - a strong elastic band would do as a temporary measure to give you the confidence to kick it properly

It sounds like you are wary of the bike - you need to adopt the approach explained by others in a previous thread and give it some gusto in conjunction with use of the valve lifter to establish a starting position.

Regards Mick

At 70+ with one replacement knee and a dicey other one I can afford to be wary of the bike! Having said that, I have been a biker since the mid 60's riding singles and twins and have never used a valve lifter, even on an 18MCS. I do have some experience, but am a little more careful these days. The worrying factor ishaving timed it so carefully, why will it not start - the G3 I rebuilt lasy winter can be started by hand, just turning the engine over! Or, tickle, turn it over twice, ign on, just touch the kickstart and away it goes! The G80 surely is not that different - it is not high compression, same stroke, engine not rebored so not tight ....just frustrating!

Hi

The benefit of the valve lifter is it allows you to rotate the engine over TDC without the risk of it kicking back as you position the engine to a point where a steady swing will impart maximum inertia/speed into the flywheel before it next passes TDC.

I certainly couldn't start my G3 by hand and would miss the valve lifter if it broke.

Regards Mick

AJB, Ive had my 61 G80 for over 25 years now and have only had a problem with it kicking back once. That was after a winter layup when the AR was sticking and not returning to the retarded positon. A bit of grease on the shaft and new AR return springs have cured it completely and yes, they can be started by hand.
I have fitted mine with a gammatronix widget as an electronic widget that doed away with the condenser altogether. It leaves a very small trigger current passng through the points so theres no risk of them ever wearing out. Starting is first time every time and a slow reliable tickover is a pleasure to listen to. Another bonus when it comes to timing is the little led on the box. Ive always set mine up at 1/8 btdc retarde as per the book and have never had a problem. With 64,000 on the original wire wound piston I must be doing something right

https://www.ebay.co.uk/itm/Universal-El ... SwzIVZcQTZ

They do these in 6 or 12v, positive or negative earth. An excellent bit of kit and cheap too.
Steve

Hi

I've had a look at the gizmo Greybeard linked above - can anyone advise me as to how this is electronic ignition? It seems to retain the points, coil and by supposition the mechanical ATD

Regards Mick