Intermitten Start Problem

[Suzuki-san]

This has started a while back, but the problem is getting worse on my 2001 GZ250.
When going to start it, hot or cold, sometimes it will just crank and crank. Then I would turn off the ignition switch, wait a few seconds, turn it back on, and it would fire right up. However, lately it takes 3-5 attempts turning the ignition switch to get it to fire, and am afraid it will leave me walking some day.
It has good gas, I add carb cleaner ever 3-4 tank fulls, the headlight is bright, it cranks pretty strong so the battery seems OK.
Once it fires up, the bike runs like nothing is wrong.
My first instinct is that it is the ignition switch, but if it was that, would it also not crank? Anyone else heard of this issue?
Does anyone know of any switches on the bike that would kill the ignition but allow the starter to turn?
Also, could the valves create such a problem as well? ...when it does not fire it sounds a bit different, but that could be my imagination.
Any feedback appreciated. Thanks!

[Water Warrior 2]

Buy yourself a can of contact cleaner. Spray some cleaner into the ignition switch. Turn the key back and forth through it's entire sweep. Repeat.

You might as well do all the switches while you are at it. Signal switch, Hi Lo beam, Starter button, basically anything that is electric.

Hmmm, should have said to first check for tightness of the battery cables. Then do the spraying.

[alantf]

Yes, this sometimes happens to me. Sometimes it would crank and not fire. Quite by chance, I found that turning the key on and off would get it to fire up straight away. Switch cleaner made no difference. Still don't know why this is happening.

[Suzuki-san]

Thanks for the suggestions. I'll do the contact cleaner next, and check everything for looseness and corrosion.

[Suzuki-san]

Originally Posted by Water Warrior 2

Buy yourself a can of contact cleaner. Spray some cleaner into the ignition switch. Turn the key back and forth through it's entire sweep. Repeat.

...

Hmmm, should have said to first check for tightness of the battery cables. Then do the spraying.

Water Warrior 2 ... I think you hit the nail on the head...

UPDATE: So my first try was to get some quality contact cleaner and do the ignition switch. The stuff I got was flammable, so I decided to disconnect the battery to prevent any possible sparks. When I removed the side cover to expose the battery, I did notice a small amount of corrosion on the negative terminal. When I took the screw out, it was FULL of corrosion.

I sprayed contact cleaner into the ignition thoroughly, then inserted the key, working the switch all round to all positions several times. I then repeated this. After a good soaking, I used a can of compressed air with the little straw and blew air into the key hole of the ignition. This was to help with the drying process.

I then cleaned the battery cable ends, posts and screws with the cleaner. I then let the bike sit overnight to dry out.

Next day I put it back together. I paid particular attention to the battery cables and made sure they were flat and very secure. I hit the ignition and starter - it fired right up.

IN FACT, IT HASN'T REPEATED THE PROBLEM SINCE I DID THE ABOVE (one week and counting).

But I'm not 100% sure which was the problem - the ignition switch or the battery. I'm not even sure if the cleaner reached the actual part of the ignition switch where the contacts are.

SOOOoooo... I can only GUESS at what was causing the intermittent start problem. My hunch says it was the battery corrosion. I have read elsewhere that when the starter is cranking the engine the voltage on the battery drops. If it has corrosion causing resistance, then the voltage may have dropped low enough for poor spark or for the ignition circuit to not function correctly. Once the engine fires and the starter is released, the voltage rises back up and the engine runs fine.

So that is the scoop thus far, and I hope it helps someone else whom may have this peculiar "gremlin" on their GZ 250. Funny how corrosion can cause such a funny problem.

Thanks again for everyone who chimed in.

It is Feb. 19. I'm in Texas, it is 60 degrees breezy and sunny... I think I'll go for a little ride right now. Seeya!

[Water Warrior 2]

Sounds wonderful. A little TLC makes life a lot easier. Ride Safe.

[jonathan180iq]

It doesn't really matter which of those two variables solves the problem - both of them are simple enough fixes that repeating the maintenance process can be done every month or two to avoid having to worry about it again in the future.