Batfink needs an electrician

[moizeau]

Now that the house is finished I thought I'd have a few hours on Batfink. After stripping more accessories off I thought I'd see if it wanted to start. Not a bloody hope in hell. Checked the yellow trace to the coils, 11.9v. Checked the green and the black to each coil with the points open, one shows 11.9 the other 10.2v. Checked the connector next to the coils on the green and the black, same result. Haven't checked the earthing on the coils. It wants to go but tries harder with no choke. The carbs need a good clean but I have fired it up before. I did hacksaw the carb to airbox rubbers and quickly looked at the float bowls and emulsion tubes, cleaned them quickly and tried again, same result. The fact that it tries with no choke would suggest to me it's flooding so the carbs will Ultra'd but the main question is the difference in the voltages? Duff coil? As said I haven't checked it's earth, will do tomorrow. It sparks, but seems weak.

Any pointers gratefully received.
Cheers

[gray]

stale fuel as 1 potential issue.
is it sparking on every cylinder?
is it flooding due to floats stuck in the down position after being dry ?
More investigation and info required please

[moizeau]

Thanks Gray, fresh fuel, it fired up 4/6 weeks ago and held idle, just more confused over the volts? The carbs will be next but it shouldn't stop it starting, wet plugs and all.

[moizeau]

All floats move freely and they don't overflow, yep I've got a small spark on all cylinders, will have another look today to see if the sparks on the low voltage set of points are weaker than the other 2.
I'm sure I've asked this previously but do the choke plungers (when on full choke) add extra fuel or restrict air?
Cheers

[warren3200gt]

Enrichers add fuel directly into the carb throat by venturi effect.

[moizeau]

Thanks

[KeithZ1R]

This could just be summat simple like the battery is tired, if your trying with the starter the battery voltage may well be dropping below the level to produce a viable spark, try a better battery or kick start before you drive yourself insane looking for issues that dont exist jiust sayin

[moizeau]

Thanks Keith, the battery is fine, it's a spare from a 2.0 HDI, 74AH 680A on jump leads. I can't use the kick because the splines on the kickstart (not the shaft) are buggered.

On the green coil wire for 2 and 3 I've got 10.6v and a LT resistance of 4.7 ohms, this is the one that sparks well.
The black coil wire gives 12v but has a LT resistance of 5.8 ohms.
I've only got a Haynes BOL's for this but that suggests it should be around 4 ohms.
The voltages are the same whether measured at the coil wire or the points.

Then I re-read the previous post 'Batfink hasn't got a spark' and followed the advice you posted then.

Opened the points up and bridged then with a screwdriver watching for a spark. The green coil sparked, the black for 1 and 4 didn't but I heard it click, decided to really test it because I was in quite bright sunlight and grabbed the plug, got a very very faint shock, just to be a muppet and compare the two I did the same with the good one.....got a smack, that works fine.

I then swapped the green and black wires to see if the issue stayed with the condenser or coil. It stayed with coil. Cleaned all the earth mountings up on the coil and checked continuity, fine, still the same.
So unless I'm missing something, and that is very feasible, the spark test along with the 5.8 ohm LT reading would suggest a knackered coil?

Just to confirm this absolutely, can I borrow a coil off the ST, are they compatible?
Is there something I should be looking into that can cause a coil to die or do they just die. The coils have been changed for gen Kwak ones in the past because I've got the empty boxes with part number in a box of bits the chap gave me.

Thanks for all the help so far

[moizeau]

Just a thought, the ST is electronic vs 650 points, does it make a difference, and another thought was instead of nicking the coil off the ST, I have the GPZ11 already in bits, would that work?

[gray]

sounds like a coil . if you've got a another coil on the bench try it, I guess it wouldn't make much difference if it was off a points or electronic bike, for a 5 minute attempt to clarify the problem. Then at least you'd know. If it runs great then you can invest in the "right " one if you want.

[moizeau]

I've just checked the different repair manuals before swapping a coil
Haynes Z650 says primary winding should be around 4 ohms
Kwak ST says between 1.2 and 1.9 ohms
Kwak GPZ11 says between 1.8 and 2.8 ohms

Secondary windings are
Z650 - 23 K ohms
ST - 12 to 18 K ohms
GPZ11 - 10.4 to 15.6 K ohms

Am I likely to bugger something up swapping in a coil from the ST or GPZ11 to verify the Z650?

Cheers

[moizeau]

Just been looking this up and 'I think' the GPZ ignition system is TCI not CDI so the coil is constantly powered so should be OK but still not convinced and don't want to burn it out until someone tells me it's OK or not to. I've read going the other way isn't an issue but very little to confirm what I want to do.
Any advice gratefully received.
Cheers

[moizeau]

Stuck the GPZ11 coil on.....in a fashion

Dropped the tank on, started on the button, no throttle cables connected but ticked over sweetly at 1500rpm.
Off to source a coil, well pleased.

[KeithZ1R]

[moizeau]

Little update, good news but a little embarrassing.
The old coil is fine. I never took the plug caps off to check the resistance on the secondary winding. I did last night to recheck everything. Both plug caps were intermittently open circuit, the screw for the lead was moving back and forth. The leads also were in a poor condition where they screw onto the caps. The chap had left a boxed brand new one in the box of bits, bought another, trimmed the leads (they are right on the limit length wise now) and Batfink fired up nicely, Will probably have to get another coil or a repair sleeve and extend the leads at some point but for the moment it's fine.
Just need to source a kickstart, they seem to be like hens teeth and a different spline diametre to the ST, oh, and a battery, it's not really feasible strapping a car battery on the back, The Zeph11 battery is about 5mm too long to fit in the box and the ST is way too big.