Hi All,
I know that I have asked quite a few questions about kick starting in the past, but I would just like to clarify something.
On my bike, I start with the switches off, and work the engine around with the kick start until it is just passed TDC. It then seems to sit in a 'notch' at that point where the points are open. Switching on the ignition shows no current, as the points are open. Is this the best place to start my kick? Or is it better to wind it on a bit further so that the points are closed?
I have found, that, if I accidentally leave the ignition on, it will kick back at this point, even if the engine is turning very slowly. Luckily, being a small bike, the kick is not very hard, but it still comes as a shock.
The other thing that happened is that the bike started on the first kick, but the kickstart lever stuck down and didn't return straight away. The engine turned over a couple of times, and then the lever jumped up with a bang, stalling the engine in the process. I was relieved that there wasn't any obvious damage, as I have already repaired the kickstart twice since I have owned the bike.
Thanks, Ian
Okay, It looks like the notch which I was feeling, is the TDC. I imagined the spark occuring just after TDC when fully retarded, but it seems that the points are open bang on TDC.
SO, I need to push the engine just passed this point without the compression causing the engine to roll over.
However, I decided to follow the advice of a mate and fit the kickstart lever from my other bike, which is in better condition and easier to kick. This seemed a good idea at the time, but It turned sour when the cotter pin sheared off and I spent a chunk of the afternoon punching the stump out with and old masonry drill.
A new pin is now on order.
The points will open at some time before TDC and remain open for quite a few degrees so it's no surprise that they are open at TDC. The best place for the engine to fire up easily will a bit past TDC where a good kick achieves maximum piston speed as it comes back up against compression. Nothing to do with where the points are open when you start the kick.
Thanks Derek,
I guess the question, should be will the ammeter be showing current at the point of kicking? i.e. the points have closed again after TDC.
Ian
Ignore when the points close, its not relevant, it just when charging the coil starts. The plug fires when they open and this will almost always be before TDC even when fully retarded.
Unless the bike is tuned (ie scrambler) you should be able to just kick it. It helps to come over compression and it helps to brig the kick start to the top, but its only 250 cc so it should be possible to kick it over with little preparation.
If its kicking back it may be that you are kicking it too slowly, the piston should be moving as fast as you can get it so even though the spark is before TDC the piston is over TDC before the real force starts.
Both my C15s have a tiny "kick" as I bring the engine up and a shade over tdc.
I expect it to have a tiny kick as the points open it will.
The critical thing that you're trying to achieve with the kicking is giving the engine enough rotational momentum to allow it to overcome the next compression and fire on its own.
Sometimes I leave the ignition on , sometimes off , but bring it just a whisker over tdc on the compression stroke , the restore the ks lever to the top , ready for a good swing
I think the cause of my confusion is the "notch", which nobody ever seems to mention when describing kickstarting. As I turn the engine over, it pops into the notch, at TDC, and then I have to actively push it out of the notch again. SO the tendency is to start the kick with it in the notch. But it sounds like the best plan is to ease it out of the notch, before starting the kick.
Maybe other bikes don't have this notch, and I will compare with my other bike when I get a few minutes.
It can be confusing. The "notch" can be the cam lifting a valve. On singles with a valve lifter this is what you feel, not the compression or TDC. Since the C15 has no lifter you should feel compression but if you are turning it over very slowly you will also feel the cams.
A cotter pin shearing is a concern. Was it loose in the arm or something?
Totally off the subject but a lot of years ago I had a 250 ajs single . Occasionally when i switched the ignition on , headlight switch , it just started of its own accord . No kicking . Was a wonderful trick . I suppose the engine must have stopped just at the right place so that when the ignition was switched on there was a spark which ignited what fuel was in the bore and it fired up . Years later I was at a vintage car show and I watched an old bentley fire up . All the owner did was switch it on then manually move the advance /retard lever to cause a spark and off she went .
Quote from: V500 on 10 Aug, 2026, 09:44 A cotter pin shearing is a concern. Was it loose in the arm or something?
I've had a new cotter pin shear.Seems to be the luck of the draw if you get a good one.Some seem to be made of the wrong spec metal,and some are ok.I bought two from the same supplier one sheared quite soon the other is ok.
Some pattern parts are made in India and are usually either not quite the correct size,or poor quality metal.
It's hard to imagine how rubbish the metallurgy must be for a cotter to be sheared as the shaft cotter and K/S are all "locked" together with no relative movement.
I too have been victim to a very poor quality cotter pin that sheared. It think they were passing off old cycle pedal ones as motorcycle parts. It was so soft the end peened over when I was trying to knock the bits out.
The reason the Cotter Pin sheared is because it is intended to do that. The Kick Starter Shaft and Kick Lever will be hardened steel, designed to not to be the first to fail.
None of it should be sufficiently stressed to fail in use. Cotter pins last indefinitely and aren't considered to be the "weakest link"
High tensile cotters are available. I fitted one to my A10 years ago. Try an internet search if you want one.
My C15 chewed through two or three cotter pins. They would last until it kicked back. One kick back and they were done.
I eventually got a 'shallow' one from this chap https://www.ebay.co.uk/itm/204996210483 and have had no further trouble. (It has withstood several kick backs.)
The kickbacks have also been 'cured'. My C15 either wants tickling, or full choke when cold. But not both - both will always be rewarded with a kickback!
If your kickstarter sticks down and then snaps back with a bang and stops the engine, this doesn't sound like the spring is returning the pedal. It sounds like there is something wrong inside the gearbox, perhaps the quadrant teeth are jamming up?
I think the reason no one has mentioned the notch, is because no one has ever experienced a notch before. This notch ties in with a possible gearbox problem and perhaps your broken (loose?) cotter pin? Who knows?
Kicking back is usually associated with over advanced ignition timing, but I seem to gather your engine is firing after TDC? On full advance, the points should just start to open when the piston is about 1/4" before top dead centre on the compression stroke.
Bearing in mind most engines will need a slightly different technique, I don't think it's necessary to position the piston after TDC, as on a vintage BSA with a valve lifter.
Just get the piston up to compression (so there's some resistance to your kick) and give it a good kick or three. If everything is as it should be, it will start. Ignore the ammeter, just concentrate on giving it a good hard kick.