Forum

[Andy Freddy]

Thanks for the tip ,I shall try that , that and not wear flip flops when doing so

[stinkwheel]

It keeps amazing me that manuals and tech-tips when using a TDC-gauge, do not take into account that the spark plug hole is under an angle, so 8,5 on the dial is not downward movement of the pioston..

But that's ok because they make up for it by the crown of the piston not being flat...

[Bullet Whisperer]

It doesn't matter about the spark plug hole angle, when the plunger of the TDC tool is 8.5 mm on its own scale, before TDC, that will do. No need to over think things!

[Duke of Wybourne.]

There's always away around everything. Problem solved on an ES2 special.

[stinkwheel]

Here's how I dealt with the points on my 612 bullet.

[jawa-enfield]

It doesn't matter about the spark plug hole angle, when the plunger of the TDC tool is 8.5 mm on its own scale, before TDC, that will do. No need to over think things!

?? But.. Phytagoras and stuff? Won't it be around 6mm in reality?

[jawa-enfield]

Here's how I dealt with the points on my 612 bullet.

Ah but you left out the spoark plug cable! You are cheating!

Ehm more serious, the drive chain to the ignition housing gives a lot of play? Where does your spark factory have it's location?

[Adrian]

It was gear drive to the "distributor" last time I looked, not chain!

The cumulative build up of clearance between the 6 pinions involved can add up to about 10° of slop or backlash by the time you get to the final one for the ignition. You can compensate for this up to a point when timing on the full advance figure by winding on the "distributor" pinion anti-clockwise to take up the slack before setting finally tightening it in position.

I believe stinkwheel has opted for an Electrex World crankshaft-mounted CDI ignition or similar. My enthusiasm for these is somewhat reduced by the rather poor lighting output these kits provide.

https://www.electrexworld.co.uk/acatalog/STK-100D.html

A.

[stinkwheel]

Ah but you left out the spoark plug cable! You are cheating!

Ehm more serious, the drive chain to the ignition housing gives a lot of play? Where does your spark factory have it's location?

As Adrian says, I fitted an Electrex one. The pros are that it's indexed on the crank and it self-excites so will spark even if there is no battery at all. Cons are that as stated, it has a low power output for lighting. I've got round this by using LED bulbs throughout. Total drain of just over 2A when all the lights are on. So effective my next job is to do away with the battery altogether in favour of a capacitor so I'll be able to move all thw wiring and various black boxes into one of the toolboxes (reg rec on the back of it for heat sinking).

The standard ignition is gear driven rather than chain driven, there's just a lot of backlash on the gears (5 pinnions between the crank and the distributor shaft).

[jawa-enfield]

But both sides of the crank are swimming in oil? But still works? Have to google it..
Indeed the backlash is a thing..