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Discussion Starter #1
Wonder if anyone has had the following issue and if so how did you resolve it?

Fired up my 2001 F4 750 after a long layup, bike fires but it sounds as if the starter gear is not disengaging, if I gently rev the engine the whine gets louder.

Any ideas what is the issue and an idea of what to do thanks.
 

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Pull the starter and see what's up.
 

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Discussion Starter #3
Pull the starter and see what's up.
Cheers Chuck, but is the starter gear assembly accessible from there? The starter motor shaft seems to slot into the engine case, or am I missing something?
 

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You aren't missing anything. Sometimes, after a layup and an issue, simply disassembly and reassembly solves the issue by freeing up components.

I wouldn't run the bike if you think the starter is being turned by the engine. It will damage the starter and possibly the engine.
 

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Of course, you could just do what we used to do "old school" with car starters...give it a whack!
 

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I just had a look through the Engine Manual. The device is called a Free Wheel in the manual...we commonly call it the Sprag Clutch here.

It is possible that this device has simply "frozen" due to thickened oil residue or other detritus.

I have not removed a starter, nor delved into a sprag replacement, so I don't have any practical advice on how difficult it may be.
 

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Discussion Starter #8
I just had a look through the Engine Manual. The device is called a Free Wheel in the manual...we commonly call it the Sprag Clutch here.

It is possible that this device has simply "frozen" due to thickened oil residue or other detritus.

I have not removed a starter, nor delved into a sprag replacement, so I don't have any practical advice on how difficult it may be.
Yep it is a free wheel assembly with a sprag built into the one way clutch, I suspect your right that oil drain down over time has allowed this to freeze up and that's what is happening. I will pull the starter motor an see what can be got at but I believe I will have to pull the whole assembly out to really get at the problem.

Hopefully not done any damage to the starter and assembly, whenI did fire the bike revs never went above 1500rpm and very short time run, less than 30 seconds.

Wonder how to access the assembly, anyone delved into this area before?
 

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Have a look at the engine manual. It is where I got my information. Removing the starter, you can at least see if the driven gear is frozen or if it "free wheels" as it should.

Any damage would be in the form of insulation breakdown due to overheating from turning your motor into a generator. Remember that the engine is driven through a reduction gear by the starter motor. That "reduction" is a multiplier when the engine is driving the starter.....
 

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Discussion Starter #11
Certainly will check that out Mitchy could be the reason, will get back hands on later this week when I get some free time. Thanks guys will report back.
 

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I know sometimes when my 1078 sits for awhile I press the starter button and it still cranks when my thumb is not even on the button.:jsm:Sticky contacts I imagine.
 

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Or the start solenoid, might be getting stuck too.
I am not keen to admit to such a deplorable act on motorcycle art, reeking of amateur hour but recently after stopping to refuel the bike wouldn't start and after checking everything else over I decided I've had enough embarrassment and decided to give bridging the solenoid a go and can confirm that if the bridge is not removed quick enough there is a slight catching sound. :naughty:
 

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Discussion Starter #15
The 750 and 1000S do differ on the starting front re pushing the button, on latter models like the 1000R they continue to crank until the engine fires or the ecu resets. The 750 and 1000S don't crank unless the button stays pressed.

I will swap out the solenoid as well as that's a fairly easy item to do, fingers crossed it could be that simple.
 

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? back to basics

Jim;
key off, short across the solenoid terminals.....it should crank no issues

key on, short across the solenoid terminals....it should start......remove the

short.....does the starter stop? if so the starter and sprag are OK, if no its the sprag

key on, push starter button, it should start ......starter keep going? it's the button

unplug it from the harness and check it with an Ohm meter

there is no Bendix gear, the solenoid is just a switch

:popcorn:
 
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