Hi All,
Following on from my struggles to kickstart my C15, I even got as far as researching the option to fit a kickstart.
Whilst this is not impossible, and has been done, it isn't really a bolt on job. However the lovely AI suggested that many fit 12V electronic ignition as a way to make kick starting easier, by providing a fatter spark at low RPM (e.g. Boyers Branson).
Is this true, or is it a myth that this would help?
As I understand it the high spark voltage is generated by the magnetic flux lines collapsing and cutting through the inductor in the ignition coil at high speed. This doesn't seem to have much to do with supply voltage, but maybe I am wrong.
I can understand that electronic ignition will be an advantage over magneto or energy transfer ignition but I cant see it making much difference to the spark compared to a points system; provided the points are in good condition and the gap is set correctly. But points will wear affecting the gap and can suffer from dirt and oxidation. An electronic system will suffer from neither of these so should provide a good accurately timed spark all the time.
Given the mileage that "our" bikes do, it would take years of use to wear out/erode points.
A set of points adjusted correctly , will give a perfectly adequate spark to start an engine.
I think your other post proved this when your pal started your bike easily.
Electronic is not a panacea
Okay, I'll park that thought for now.
I've been kicking away on the bike again this morning, but no go. I even strapped on my exercise weight belt.
I'm not sure it will help, but my 1960 c15 has electronic ignition and the bike starts first kick every time.
That may sound a little far fetched but it is the truth, firsdt kick from stone cold and she fires up.
Does it do anything when you kick it over, maybe the odd fire but it doesn't pick up?
If you get nothing, have you trried a shot of petrol straigt into ther plug hole, and see if you get at least one fire off.
It may not be an ignition problem. The electronic ignition makes for more stable and accurate timing and a smoother advance curve but it makes little difference to starting.
Well, the plug is wet. I tried squirting Easy Start into the bore but it didn't help. The carburettor is new, and it was running yesterday, so the timing must be close to correct. What else is there? It must be technique, but it is getting beyond a joke.
My spare battery is on charge, so I can try that next.
I am getting more confident about kicking through without worrying about it kicking back, but it hasn't helped yet.
I am not sure if it has fired at all, or if it has just been the 'chuff chuff' of the compressions.
I even had thoughts of buying a roller starter, but they aren't cheap!
Where in the country are you? I have a roller starter you're welcome to borrow for a few weeks. I used it to sort out a 350 Matchless that just refused to run. The roller allowed me to make adjustments and get it to the point where its an easy kick starter. I'm near Heathrow.
I'm in shaftesbury if that's nearer
I checked the voltage on the battery and it was down to 4V. So I dropped in the fresh battery which showed 7V. Straight away there was a difference, the bike coughed and tried to start, but it didn't last. After a few kicks it was back to nothing doing.
So, it looks like the battery isn't charging. After sitting ticking over yesterday, it should have been nicely charged up.
Thanks for the kind offer of roller starters, I am near Portsmouth, so not super close either way.I'll investigate the charging first.
Could be a duff condenser that's near end of life.
Make sure the bike's not too advanced. To begin with it's better to have it a gnats retarded. Have you tried kicking it without the plug in to dry the bore, plus Dry the plug and don't tickle the carb to start. Too wet will kill the spark.
Plug cap might be faulty. You could try bare wire straight to the plug.
Well, the rectifier has definitely had it. I started buzzing out the circuit and the terminal fell straight off. It was oxidised and had already been badly patched once.
As long as you have dc to the points it should work. The rectifier shouldn't matter in terms of ignition.
Since you seem to have a 6V system make sure there is a good 6V getting to the coil. The voltage at the coil should be more or less the same as across the battery. A 6V system is more susceptible to voltage drops due resistance at switch terminals, connectors etc. Which is quite probable on a 50-60 year old bike.
There could be several things going on here. Get a known OK battery, put a 6v charger on it and connect that to the ignition with everything else disconnected. I have a suspicion that the rectifier is shorting so not only is it not charging but it may also be running the battery down very fast.
Like I say, the terminal on the rectifier was seriously corroded, so it must have added some resistance. We will see.
SO, which is the prefered electronic ignition of the moment, Pazon or Boyer?
You should get a bike running well on the points before you move to an electronic set up. Otherwise its very hard to know where to start if there's a problem. On a bike like a C15 there will be little difference so you can ride for a while fine tuning the mixture and timing before making a change to electronic.
Electronic ignition introduces a number of problems so its only worth it is the engine runs better. Tuned and high revving engines can run a lot better on electronic, but bog standard ones can run better on points. Electronic ignition requires a first rate charging system and battery and that can be a struggle on an old bike.
Okay. Taken on board. We will see what happens on Friday when I try it out with the new rectifier. I bought one of those £5 solid state ones from Ebay, rather than shell out on an original replica. I take it that is Okay at least?
Clean the earths and battery connections and keep the old rectifier as it may be recoverable. The problem with jumping to an electronic ign is that they can (and do sometimes) fail and its very hard to know whether you have an ign fault or a mixture problem. With points know what you have, they are not perfect but its easy to check that they are working.
Points set up is perfectly adequate.
The £5 solid rectifier work well.
I can't remember if you have a regulator somewhere on your bike or if you're running an original set up
What size battery do you have? What ampage?
Without going daft, any size of 6V vehicle battery would be sufficient to start this bike.
In the past I've used a PP3 9 volt battery to test ignition, with great success.
I'm running a Motobatt MBT6N4. I reckon this should be fine. If the ammeter is anything to go by, it looks to be putting out about 2A into the coil.
Is it true that I shouldn't run a Gel pack battery with a standard rectifier without regulator?
See Hugh's video : https://www.youtube.com/watch?v=VFg4LA0qYWI
Always need some form of regulator, whatever the battery.
C15 didn't originally have one, but maybe it is a good idea
at 02;43 Hugh says exactly what is correct
the older English bikes did rely upon the physical bulk/mass of the battery to absorb ?"regulate" the charge coming from the alternator.
the stator coils were rudimentarily switched in and out by the lighting switch as more load(eg headlights) was put upon the battery system.
nowadays, we have the luxury of modern electronic regulator /recifier to manage our charging system far finer than ever before
he had originally the little square rectifier (that you are waiting for delivery) and has replaced it with a 6 volt REG/Rec to control his charging
I now avoid gel batteries. I've found they do not take abuse so well and I've had several fail earlier than I would expect for the money. I cheap basic small Japanese battery does fine. These simple systems can over charge and so you want a vent tube and check the level every few months.
Whereas I always use those cheap £14 maintenance-free batteries from Ebay etc. Last a couple of years, but for that price I'm happy.
No acid spills or topping up required either.
Perhaps its because they are cheap : ) I paid a premium for "long lasting" and they were anything but.
It makes sense to do away with the Lucas system of varying the alternator output by switching in/out coils depending on the load and to fit a modern rect/regulator. The battery on my Ducati Scrambler, a Yuasa AGM battery, lasted 11 years. The one on the Supersport that I sold last month was 9 year sold and still working well and these are bikes with electric starters. The key to long battery life is good voltage regulation.
I fitted the new £5 rectifier. First kick the bike fired but didn't catch. Second kick the same, and then after that it didn't want to know. So I put some charge in the battery, but the result was similar.
I ordered a regulator yesterday, so let's hope that fixes the issue.
With respect a new regulator isn't going to fix a bike which doesn't fire. A charged battery is all it needs. You need a running engine and charging alt before the reg becomes into play.
You can always try starting your bike with the battery actually on charge , won't hurt , gives a know voltage into the bike.
If it does fire and stay running, unclip the clips then.
Maybe it depends what reg you go for, but my understanding is that the reg will boost a sagging voltage if the battery is getting a bit flat, and it sounds like I should be using a sealed battery in conjunction with a reg anyway.
Alternatively I have a dry acid battery on the shelf which I could drop in, which I bought for a previous project and was never used. I might have to nip out for some battery acid. Do they still sell that in Halfords?
All of that said, I have managed to get the bike to start twice this afternoon. It looks like choke, but no tickle might be the way to go.
Weirdly, it sometimes fires and tries to start, when I am just slowly turning it over feeling for TDC. Then, when I really kick it, it doesn't want to know. I wonder if it might be a timing issue?! That said, once it is running it sounds absolutely fine.
I might have to check the timing.
Quote from: Barnsey on 11 Sep, 2026, 14:50 ...Alternatively I have a dry acid battery on the shelf which I could drop in, which I bought for a previous project and was never used. I might have to nip out for some battery acid. Do they still sell that in Halfords?
I think you will struggle to find acid anywhere now. It's sale was made illegal several years ago following a spate of acid attacks.
QuoteWeirdly, it sometimes fires and tries to start, when I am just slowly turning it over feeling for TDC. Then, when I really kick it, it doesn't want to know. I wonder if it might be a timing issue?! That said, once it is running it sounds absolutely fine.
If it's too advanced it will kick back but you'll know about that soon enough. Too much retard though can make for difficult starting where the bike will fire but won't pick up. And of course the correct setting for the pilot mixture is important but you can't get that right until you've got the bike to run.
I usually kick over my ZB32 on a closed throttle and it starts easily, 1st or 2nd kick. But on one occasion, when the engine was still cold I screwed up the throttle stop a little to keep it running while I put my gloves. I rode off, got to my destination and parked up. An hour later when I tried to start the bike it wouldn't even fire. I got a push and away it went. When I got home I realised the idle speed was a bit high so I wound it back down for a better idle. Next day starting was restored to normal.
There are so many variables that affect good starting that you have to be methodical and only make one adjustment at a time and note any difference.
Even if you're lucky to find actual wet acid anywhere, you still need to check the Specific Gravity of it having soaked into the empty dry battery.
Filling batteries with acid etc is not a 5 minute job.
Just use a spare 6v battery connected to your bike , maybe on charge still and try to fire your bike up.
I did PM you a few days ago
Quote from: Barnsey on 11 Sep, 2026, 14:50 I might have to check the timing.
Maybe, but it would be better to go back to basics and check everything again from scratch. Then again, a timing issue isn't going to cause a "it fires a couple of times, then it's dead" scenario.
Jumping from one possibility to another is just a waste of your time.
An update for today.
I added a grounding wire to the rectifier because the shell on those square ones isn't grounded, unlike the old style ones. I am sure this pushed the current up a bit, although the smiths meter doesn't have a scale. Actually I am tempted to see if I can buy a digital gauge that would fit in that hole. Not very in keeping but it would give more meaningful info, possibly including voltage.
More importantly, I tried a change of tack re kick starting. I started the kick with the engine just before TDC, rather than after, and that worked, it fired straight up. Is this Okay as a technique? Or might I come unstuck?
As long as the + or - terminal of the little rectifier (depending on whether you are pos or neg earth) goes to the same earth.
The little 12v square rectifier work well to get your charging going.
Eventually , you'll swop it for a reg/rec to get regulation sorted.
Get him started and do your voltage checks
As far as starting technique , if it works reliably for you , then why not !!
Kick starting? Anything that works is good. Starting just before TDC gives you a longer kick to build up flywheel momentum. Because you are light this may be the solution.
Is it now running well enough to set the idle mixture and speed?
I set out to set up the idle and mixture, but my workshop was filling up with fumes, even with both doors wide open. So next I need to get it outside again. Maybe tomorrow. Unfortunately the steps make getting it in and out less than trivial. Maybe I should build a ramp.
I have been practising the kick with the switches off. I think the tricky thing is the the motion of the kickstart changes from vertical to horizontal , at the bottom of the stroke. It is harder to keep the kick going at the bottom, but vital in order to kick through TDC. I am sure that those used to doing this wouldn't even notice. Maybe that is why my unorthodox technique worked.
Quote from: Barnsey on 12 Sep, 2026, 19:20 I set out to set up the idle and mixture, but my workshop was filling up with fumes, even with both doors wide open. So next I need to get it outside again. Maybe tomorrow. Unfortunately the steps make getting it in and out less than trivial. Maybe I should build a ramp.
I have been practising the kick with the switches off. I think the tricky thing is the the motion of the kickstart changes from vertical to horizontal , at the bottom of the stroke. It is harder to keep the kick going at the bottom, but vital in order to kick through TDC. I am sure that those used to doing this wouldn't even notice. Maybe that is why my unorthodox technique worked.
It sounds as though you have found a starting technique that works for you and hopefully problem solved . I may have missed it in the thread but if you do still get recurring problems with starting there is a chance that on an old coil you may have either a break in the secondary winding or a bad internal connection. This can lead to weak spark or virtually no spark. The easiest check,if you haven't already done so is take the plug out, rest it on the head and kick the engine over to see if there is a good fat spark. Ive had it a couple of times on car coils, hard to start but once running ok.