Timing without dial gauge

[Farmingstock]

Is it possible to check timing without a dial gauge?

Got a 94 KTM SX 250 and it’s sneezing and popping back when trying to start, my foot is black from trying to kick it over.

It has a HPI ignition on it and as far as I’m aware it should be 2mm before TDC and on the second big line on the stator, only issue I can’t accurately measure TDC (well 2mm before) I have bought 3 different dial gauges and neither fit, so they have all been sent back! I would need to cut some off the stem to make fit or take the engine out completely! Either way, before I order another would there be any other reason for the sneezing and hard not starting/kick back? Carb is definitely clean!!!

[Pete.]

You don't need a dial gauge you just need something to screw into the plug hole to act as a dead stop for the piston. An old spark plug with the guts knocked out and a piece of dowel inserted in the hole would do it. Turn the engine forwards (gently by hand) until the piston hits the stop, mark the flywheel next to the timing mark. Now turn it backwards until it again hits the stop and mark the flywheel again. TDC is right in the middle between the marks. If the marks are too far apart shorten the dowel until they are close enough for you to mark the mid-point accurately. If you get them 4mm apart then one mark is your timing point.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[stinkwheel]

One of these?
https://www.feked.com/tdc-timing-tool.html?srsltid=AfmBOop3ZueUd1auaAB_QbiPJ2sETMWnc_URKxet61vI5rhu6awSVxh8

Or use it to find TDC (or with a dead stop tool as per Pete.s post) then use a degree wheel on the end of the crank and strobe it.

mmBTDC is a bad way to get the timing point anyway. It's just giving you static timing and most electronic ignitions have an advance curve, so the firing point will change according to revs. Some even have an extra retarded timing point at very low revs for easy starting.

I was having real trouble getting my enfield to run properly on an aftermarket electronic ignition. I'd got it set up bang on (it even had a vernier scale on the back plate for setting the degrees BTDC). When it strobed it, the timing was all over the place. I put the points and mechanical ignitin advance back on and the problem went away.

Or go old-school and just try retarding it a bit at a time until it starts easily.

Is the timing even adjustable? Most modern bikes I've worked on have it keyed in making measuring the ignition timing a bit of a moot point.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Farmingstock]

This is how they are, it’s not a woodruff crank with this ignition on, just tighten down, I’ve watched several yt videos but they all use a micrometer!

[Farmingstock]

Just checked the timing again and it looks spot on, the last time the bike started it was almost forcing fuel out of the carb like pressure was coming out of the inlet, I’ve checked the reeds and carb both clean and fine!

Now the bike won’t start my foot is in agony from kicking it over, the bike is kicking back to which is dangerous! I definitely think it’s timing related, however it seems very close to perfect and makes no difference if I adjust slightly.

When kicking over it’ll just cough/sneeze and a cloud of smoke will come out near the barrel, definitely looks like timing is out but I’ve don’t what was suggested and it looks spot on, the flywheel hasn’t moved, it has spark it’s not thick blue, but it’s a racing plug and was the same when it was running fine!

[stinkwheel]

Sounds like the behaviour of an engine that's 180 or 360 degrees out. I presume it's a lost spark?

Has it actually run with this setup?
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Farmingstock]

I’ve taken everything ignition related off the bike, checked everything as good as I can, refitted and the bike has fired up perfectly! I don’t know what I have done, everything has gone back on exactly the same way as it came off and I haven’t changed anything as far as figment, timing back in the same pen marks don’t know what I’ve done, I think I’ll mark the nut on the crank with tip ex just to make sure that doesn’t move[/code]

[stinkwheel]

Tightening down a rotor onto a plain taper can be tricky without something rotating out of position in the process. No easy way to hold the crank stillI'd guess this is what happened. It's why manufacturers use woodroffe keys.

My electrex one was like that (fits to the crank with a tapered collet). You needed to somehow hold the crank and rotor still and in the same position as you tightened down the central bolt. Either could try to turn as the bolt gripped either the rotor face or crank thread. I landed up seating it on the taper with a mallet then jamming up the primary gears with a piece of folded denim to stop the crank rotating, THEN holding the rotor still with a big spanner while I tightened down the central bolt.

You should still strobe it. Dynamic timing is the only way to be sure.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Fizzer Thou]

KTMs are notoriously bad for fitting dodgy spark plug caps that are cheap and not up to the job.Indeed,on the KTM UK Forum quite a few people said that they would carry a pocket full of them to fit as and when they experienced an ignition problem.Taking this into account I fitted an Iridium NGK spark plug and a new plug cap from the same people and not had any problems since.Friends with other versions from KTM have since done the same and appear to have found the right combination and now run a more reliable ignition.
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Just talk bikes.What else is there?

Always have a 'Plan B'