starter chain problem

[Pete in PA]

I'm sorry but cranking speed for an engine is not 7k. it's below 1k.

Before I would pull an engine from a frame and then split the cases I would exhaust ALL other possibilities.

With the starter removed, try squirting a non syn, plain old dinosaur 10w-40 motorcycle oil on the starter clutch.

I'd remove the spark plugs to lessen the load and try to crank the engine. I'd remove the timing cover to make sure the crank is spinning.

[Hend238]

seeing 7k and not starting have to be related. Something weird is going on.

Have you tried to bump start it in 2nd gear yet?

I have not. I'm hesitant to have the motor actually running if there's a failed component inside that could cause further damage.

[Hend238]

The tach doesn't have anything to do with the starter chain.  However, if things are spinning freely inside the crankcase, maybe the pulse generators are actually giving correct indications that you're turning over at up to 7k even though the engine actually running.
Another thing to do could be to have the bike in neutral and watch the alternator vanes as before, but have someone hit the start button.  The starter and the alternator run off the same chain so this would confirm that the chain is intact.
If the is the case, I can only assume that something major is amiss in the guts somewhere.

You're along the same thought process now that I am regarding the signal from the pulse generators. I'll spin the starter in neutral and see if the vanes rotate.

[Hend238]

I'm sorry but cranking speed for an engine is not 7k. it's below 1k.

Before I would pull an engine from a frame and then split the cases I would exhaust ALL other possibilities.

With the starter removed, try squirting a non syn, plain old dinosaur 10w-40 motorcycle oil on the starter clutch.

I'd remove the spark plugs to lessen the load and try to crank the engine. I'd remove the timing cover to make sure the crank is spinning.

Fair enough regarding cranking speed under normal conditions but the question should be what is the rpm of the starter when there is no load? Is it possible the little pinion is spinning that fast? Could be. I've watched it with my own eyes. No way to tell accurately by looking of course and I don't have the tooling at home to actually measure it.

Agreed, I'm in no rush to pull the engine. That's why I've asked for the help of the forum before I do something stupid. It helps my thought process and troubleshooting to bounce ideas off you guys.

Thanks for your other troubleshooting ideas. Good advice. Particularly about pulling the plugs.

[Hend238]

Thanks for the all the help so far guys. This sure is an interesting snag. Part of me is enjoying the learning experience. The other part of me is disappointed because I won't be able to dive into this fully for several months. I doubt my Nighthawk will see the road until next spring. Winter comes early here.

I'll update this thread when I have more info.

Until then....

[mollusc]

I'm sorry but cranking speed for an engine is not 7k. it's below 1k.

Agreed.  But if the starter is unloaded -- that is, if things are spinning freely -- could it get to 7k?  I don't know.  Issues with the ignition/tach aren't going to make the starter spin freely though.

I have also seen strange behaviour from the tach when battery voltage gets low, so that's a possibility there.

[Hend238]

Good morning.

Battery is definitely fully charged with good capacity. I serviced the battery just last week after a long winter of storage. I keep my battery on a tender. Keep in mind that I only see RPM indication when the starter is installed. It's a mechanical related issue, not an electrical but I think we've established that.

[Bob H]

I only see RPM indication when the starter is installed.

Are you 100% certain the engine is not turning over when you attempt to start it?

The Tach display is interesting - but unimportant.
It that was my bike I would pull the spark plugs (compressed air first, blow out the dirt and crud).

With no compression I would crank the bike and figure out if air is blowing out the holes.

[mollusc]

Agreed.  Pull the spark plugs and place a chopstick in one of them, then crank the starter for a moment to see if the chopstick moves up or down.

[Hend238]

I only see RPM indication when the starter is installed.

Are you 100% certain the engine is not turning over when you attempt to start it?

The Tach display is interesting - but unimportant.
It that was my bike I would pull the spark plugs (compressed air first, blow out the dirt and crud).

With no compression I would crank the bike and figure out if air is blowing out the holes.

At the most the bottom end is turning over. The tack reading supports that in my opinion and is why I feel it's an important part of this discussion. I can hear gears and shafts turning but there is no load or compression. Basically a freewheel. If that's 100% accurate then we're back at the starter clutch slipping under load from the starter.

[Hend238]

Agreed.  Pull the spark plugs and place a chopstick in one of them, then crank the starter for a moment to see if the chopstick moves up or down.

I'll add a chopstick to my special tools box. A simple yet effective test. I have yet to follow up on your suggestion of cranking the starter while observing the alternator cooling fins. If I have time before I leave for work, I'll set up and carry out the most recent troubleshooting suggestions from you guys.

[Pete in PA]

When was the last ride and how was it before this first happened?

Do you use ethanol fuel?

[Hend238]

When was the last ride and how was it before this first happened?

Do you use ethanol fuel?

20 mins before. A quick trip into town to run a few errands. 4 days previously I had it out for good burn. The bike ran like a top.

I never run ethanol fuel. I stabilize the fuel when I leave town for work. I'm on a 4&4 week rotation.

[Hend238]

Ok gents I have an important update. I feel a little foolish because I was certain of a few things that turned out to be false.

The bottom end is NOT turning over. As Bob H was eluding to in an earlier post.

I pulled the alternator cover, pulse generator cover and one spark plug. I knew there wasn't any compression so I didn't bother pulling the rest. I hit the starter and kept an eye on the chopstick, pulse gen rotor and cooling fins. The chopstick and rotor didn't budge, the cooling fins did but not for long. Maybe 10 deg max. RPM hit 5500 but I didn't hold the starter but for a few seconds.

My observation earlier about seeing the cooling fins rotate with the rear wheel were obviously incorrect. I just didn't get enough of a turn to confirm what I was seeing.

So, the RPM thing is interesting but as Bob H said, it's unimportant. It's going to keep me awake at night though until I figure that one out! But I guess when the starting issue is fixed I shouldn't see the RPM spike anyway. Still, I'd like to understand why. Enough of that.

It was suggested that I squirt some old fashioned dinosaur oil onto the starter clutch to see what happens. I have not done that yet.

It's looking like a bad clutch. Agreed?

[mollusc]

Quite possibly.  The vanes on the alternator moving a small amount would seem to indicate that the chain is still intact.  If it is, then you probably DID see the vanes move when you bumped the rear wheel.
In any case, repair isn't likely to be a simple affair.