Timing Advance

loudhvx wrote: I was able to locate my factory 440 manual (on pdf). If you want a copy of it for online use, let me know.

You usually don't have to remove the cam shaft to change cam timing, but sometimes you have to remove the sprocket from the cam in order to get enough slack (in addition to removing the tensioner).

If you're lucky, simply releasing the tension on the tensioner may get you enough slack to walk the chain (if, in fact, you need to do that).

I read a warning on the tensioner, though, that you should not remove the tensioner partially, then try to re-install it. It must be removed completely before re-installing or you will have too much tension on the chain.

I haven't looked up the process in the manual for the 440 yet. I'll look at it a little later.

Thanks. I do have the manual (which I retrieved from the KZ400 site - God bless 'em). So, we seem to be looking at the same page. It's too damn cold to work in my unheated Nebraska garage right now, so this is on hold. As soon as we get a warm day I'll go hook up a timing light to be sure that I have fire (which I'm pretty sure that I do), uncover the timing advance just to be sure that it didn't break or something, pop the cam cover and check the cam timing. While the cam chain tensioner is off I'll have a chance to give it a good cleaning and measure the cam chain to see if it might have stretched beyond usable limits. At 11k miles, I'm hoping that isn't the case.

I really appreciate your taking the time to think about this. After all, when it's finished it's still just a 440 and not the most interesting thing that crosses this list.

Oh, and I'll check on the accuracy of TDC while I'm at it.

Very interesting, and tricky little tensioner design. The ball bearings get wedged against the tensioner shaft when the shaft is pushed to retract, but they loosen when the shaft extends.

The lock bolt on the end is really just there to allow for installation. It temporarily holds the shaft retracted so you can mount the tensioner. Then you loosen the bolt to release the shaft and is shoots out to press on the chain guide.

Well, hopefully it'll warm up enough to work on it. I always put the toolbox nearest the heater. Nothing nicer than a warm wrench when it's cold as hell out.

I've pulled apart several "automatic" tentioners, only to find that they have self scuffed/marked themselves into position and no longer move after sitting - even just over a season.

Good thing its a pretty easy little maintenece thing to pull/clean/check and reinstall. Just be sure to follow installation procedures correctly.

loudhvx wrote: Well, hopefully it'll warm up enough to work on it. I always put the toolbox nearest the heater. Nothing nicer than a warm wrench when it's cold as hell out.

Sure thing!

I bought myself a little propane tank top heater (looks like two mouse ear burners). Throws off 40,000BTU on high. Best addition to my garage as of yet!

TeK9iNe wrote:

loudhvx wrote: Well, hopefully it'll warm up enough to work on it. I always put the toolbox nearest the heater. Nothing nicer than a warm wrench when it's cold as hell out.

Sure thing!

I bought myself a little propane tank top heater (looks like two mouse ear burners). Throws off 40,000BTU on high. Best addition to my garage as of yet!

That would be sweet, IF only the wife would let me have a butane heater anywhere inside the building. Yes, I know it's no big deal but I can't sell the idea. Anyway, thanks again and I'll likely renew this thread in a month or so when it gets a bit warmer and I've screwed up something else along the line. I know my work. The big difference between me and somebody who knows what they're doing is that they only do it once while I seem to go back into things several times to correct my own errors.

mwriders wrote:

faffi wrote: Hook up a strobe timing light and see if you actually have a spark taking place inside your engine when cranking. The simplest test you can do. If the light flashes, you have spark and can check the timing. No flashes = no spak = dead engine, and you need to find the source.

OK. Hook the strobe to what, exactly? Like I normally would to check dynamic timing?

Yes.

It finally got warm enough to work on the scooter ('80 440B1). So, I pulled off the cam cover to check the cam timing, which is just fine (damn it). I really thought that was going to be the answer, since it made the most sense. Now I've verified that I have compression, spark and fuel. TDC is in fact TDC, points gap is correct, ignition timing is correct (static check only), valve lash is correct and float levels are correct (clear line method). Got it to start (with difficulty) and run (poorly)and it's firing on both sides. The problem of not returning to idle is back when the engine is revved above 3000 rpm. On the plus side, it does sound stronger when running. But then, at this point, running at all sounds good to me.

I guess the next step is to go back to the timing advance mechanism as the culprit.

Oh, yeh, and now the horn sounds whenever the ignition is turned on. Must have pinched something while I had the tank off to check the cam timing.

Primitive little engine that it is, this thing is driving me nuts.

Yeah, if the problem came on suddenly, then you should start by troubleshooting the electrical problem. That may be killing the ignition.

loudhvx wrote: Yeah, if the problem came on suddenly, then you should start by troubleshooting the electrical problem. That may be killing the ignition.

Well, it's kind of hard to say when the problem began, since it wasn't a running bike when I acquired it. I'll get it to work pretty well on the stand only to have it fail on the road. Go through the trouble shooting series again and come up with an entirely new set of symptoms. Then I'll get fixated on what seems like the logical solution. This month it was cam timing. If nothing else, the experience has improved my tool collection.

At this point the only things that I haven't actually had off the bike are the timing advance mechanism and the cylinder head.