Cota 247 Motoplat Ignition Set-Up... Clueless!

[riffraffretro]

OK, so in the absence of a spark on my 247, I guess it's time to overhaul the ignition set-up... Motoplat system.

I've purchased a flywheel puller, timing tool (plug type), points and condenser, but being new to the old-school points system fitted, I'm clueless as to how to proceed.

Can someone clarify:

1: Rotate flywheel clockwise to fully open points, as viewed through flywheel 'slot'?

2: Remove flywheel using puller tool, then set points gap accordingly - what is the specified gap?

3: Insert timing tool in plug hole, then rotate flywheel clockwise (loosely refitted), until TDC is reached - then further rotate flywheel clockwise until the required BTDC piston position is reached? What is the BTDC value and how does it relate to the scale on the timing tool - graduated 5cm scale in increments of 1mm?

4: Re-check points and adjust accordingly to achieve correct gap at specified BTDC position?

5: Fit new condenser, then reassemble?

Is that it, or am I missing something?

Thanks again.

 

Edited November 15, 2017 by riffraffretro
Detail

[lineaway]

 I would change out the condenser first. In fact you can relocate it to the frame by the coil. Save you a lot of frustration if that is the only problem since you have no points experience.

[2stroke4stroke]

Alas, the points cam is part of the flywheel so you can't set the gap with the flywheel off - you have to fiddle about through the slot in the outer face of the flywheel.

[cleanorbust]

Please see my pm - hopefully of help.

[b40rt]

Must be a market for dummy flywheel centres to make setting points / timing easy !!!!

[keychange]

Agree with lineaway - with no spark at all first check the condensor and make sure it is earthed to bare metal. 

I had a hell of a time trying to get timing  right with spark advance TDC measure.  Timing disk 21 degres BTDC was the solution for me (see attached).  Points gap 0.4mm .0157 inch  - spark advance on TDC 2.5mm

timing.disc.pdf

[keychange]

Forgot to mention many owners including myself have removed the condenser from the timing area to underneath the tank mounted with the coil.  Much easier to get at ...in my case I just left the old one in situ with wire removed and installed a new one but remember to ensure a sound earth which can require scraping paint or powder coating

 

Edited November 15, 2017 by keychange

[riffraffretro]

Thanks for the info guys... all very helpful, as always.

I'll definitely relocate the condenser, but will need to look at the timing as the current points set are rusted shut!

[keychange]

53 minutes ago, riffraffretro said:

" the current points set are rusted shut!

Well that'll do it

[turbofurball]

I'm experiencing an issue, and just need a sanity check - should the wire that runs to the live side of the coil read as shorted to earth at any point?

I've got no spark, and as a quick check of my recent kill switch wiring I found this to be the case ... is it a short, or something to do with how the Motoplat system works?

[keychange]

On 11/16/2017 at 5:23 PM, riffraffretro said:

Short

Make sure your points aren't earthed when open - if they are you haven't installed the insulator on the pivot correctly 

[turbofurball]

I'll check on that, though the points have been on there for a good while I guess it might have broken up or something weird like that

[keychange]

On 11/16/2017 at 5:23 PM, riffraffretro said:

Short

If the points are ok then check condenser ( just disconnect from frame )  as a faulty one could short to earth as could a buggered coil.

[keychange]

You asked " should the wire that runs to the live side of the coil read as shorted to earth at any point? " well yes when the points are closed ...that's why they are called breaker points.

[oldaz]

Try dis-connecting the kill switch and check again - divide and conquer.