Starter turns, but doesnt engage engine?

[kingkevo25]

Bike wont start 

Regulator rectifier was confirmed faulty, and started fine when jumped. So I changed that. But while I was at it, I figured I might as well change the chain and sprockets. Now my bike won't start at all; it sounds like the starter motor just spins but doesn't engage!! I can't push start the bike either. Any suggestions anyone? The only thing I can imagine was that I damaged something during an attempt to remove the front sprocket... but that doesn't seem likely, does it? 

[Falk]

how about your Battery?
verry oftenwhen the Reg dies it takes the Battery with him?
Even when you Batterie shows 12V in iddle, it can break down, when you try to fire up your bike.
Please note 11V are enough for turning the Starter but to less to make the CDI working.

[kingkevo25]

Thanks for the suggestion... I think the battery is fine; I replaced it a few months ago. I think the problem may be mechanical; like I said it sounds like the starter motor is just spinning freely. But on top of that, I tried push starting it but with no success. Is there some sort of compression release system on the cb1 that might be malfunctioning? All fuses are good.

[a_morti]

Assuming your description is correct, the fault is your starter Clutch. They are known to fail occasionally.

One German member had a solution to a worn SC but don't know if it will fix a failed one. Also can't remember who it was!

[Kai Ju]

Did you recently switch to a synthetic oil ?
I've seen a couple of starter clutches fail after the owner introduced synthetic oil to the engine. I even replaced one in an 86 Nighthawk S only for it to come back after the owner started using Mobil 1. Once we flushed the Mobil 1 and replaced it with petroleum based oil it started working again.
Regarding not being able to push start the engine, did you mean that you physically can't move the bike or that it moves but won't start ?

[a_morti]

If the battery has been killed by repetitive starting attempts then it also won't bump start. Well it might just about catch (unlikely) but it won't then be able to idle.

[kingkevo25]

I can roll the bike, but I can't get it to bump start... I've been running full synth for a long time now with no problems.

Now I'm thinking I'm misdiagnosing the problem... I believe the engine isn't catching because the starter seems to be spinning more freely than ever before... but I was thinking that this might be because there is no current being drawn elsewhere... is it possible the the regulator rectifier burnt out the spark unit, or some other electrical component? Fuses are fine...

[rigwit]

There's not much to check cdi unit, but first unplug the rec/reg  3 yellow wires should  5 ohm to any yellow/yellow for cdi ... ignition on-engine run switch on cdi unit power input Black/whitetracer, and ground should be battery voltage. .Pulse generator-yellow wire and white with yellow tracer 340 -420 ohm.  Ignition primary coil 1-4-black with white tracer and yellow with blue tracer- 2 -4 ohm,       primary 2-3 black with white tracer and blue with a yellow tracer 2 -4 ohm.

[kingkevo25]

Thanks... I also did the checks in the service manual... Most of everything seems to be okay; all switches, everything.

One test I couldn't complete was the secondary coil resistance test. Primary works, but I can get neither pair of the secondary coils to give me a reading. Now this doesn't make much sense to me that I can't get a reading from either pair... I highly doubt both have gone bad but what do you guys think? Is there a trick to doing this test? Is there a specific way to probe the boots?

It seems to coincidental to be the problem, so at this point I'd assume it's a defective cdi unit, according to the testing flowchart. Thoughts anyone?? Any other plausible reason why I wouldn't get spark? Timing or something?

[rigwit]

One thing you said, after first starting, you put new sprockets on...then it would not start after......have  you checked switch on side stand has not been broken or wires come off..................

[a_morti]

If starter is spinning and not engaging with the engine then  IT'S THE STARTER CLUTCH.

This is as good as Internet diagnosis gets. It cannot possibly be an issue with the charging system.

[kingkevo25]

Side stand switch works, according to the service manual test, and the light indictator works as well.

I figured it was the starter clutch as well because the starter motor seems to whine faster than it normally did, but upon closer inspection I can feel the exhaust exiting when cranking. I will try to push start again later today! Otherwise I have narrowed the issue down to secondary ignition or spark unit.

[a_morti]

If it is actually spinning faster, loss o compression?

[kingkevo25]

Well thats where my noobness kicks in... I really believe it's spinning faster simply because it sounds like it is... but whether this is because it has a loss of compression, or because it's drawing more amps is what I'm not sure about. I do feel exhaust exiting the pipe, but I'm not sure how strong it is expected to be. Possibly the starter clutch is slipping?

Also today I checked the cdi... I popped my cdi into a cbr600f3 and the bike started up absolutely fine. The f3 cdi did not make a difference on my bike, but at least I concluded that the cdi works. I'm trying to check the fuel cutoff relay next... I'll try to make a video tomorrow of the bike trying to start and maybe that'll be worthwhile.

Thanks for everyones help!

[Falk]

I'm a little bit confused right now. From some points you describe it sounds to me like one of the typical electrical Problems, on the other hand there's the story with the starter clutch.
I mean i have seen a lot of starterclutches that were making a Ducati-like-noise in low range RpM but never a Clutch that doesnt turn the engine. And when you feel exhaust when pressing start - it turns the engine. There's nothing than just air coming out because your bike doesn't fires up - so it's not much volume of exhaust at this point.

I would suggest folowwing steps now.

• try to start with an external batterie
• try to start with an external batterie and drop some fuel directly into the carbs (not much only some drops)
• check if the spark plugs are working
• check your motor oil if it looks some kind strange - if you have fuel ore water in the oil you have a prob with your engine
  

• check fuel pump - directly connect it to 12V - check the breaker unit at the pump

Please post the result so we can provide more informations