'77 GS750 starter clutch problems

[dahlstrom]

Hi all, I've read through some past posts and haven't been able to find something quite like my issue, so I'll be happy to go read any if anyone remembers the last time they answered this.

My GS750's electric starter isn't getting the engine going. The starter motor actually is working fine, it whirs and turns like it should, and spins the bigger gear that's right behind the clutch and magnet/flywheel (correct my terminology if I'm off). However the clutch and magnet aren't spinning at all like I'm thinking they should.

So first - do I have that right? Big gear is spinning, so the rotor-clutch component should spin too. If so, is the clutch the problem here? And if it is, how do I get the damn rotor/clutch off? I've seen a bunch about clutch removal bolts online but the size and threading to this crankshaft bolt had the guy at Home Depot thinking I pulled it out of an alternate universe.

Thanks in advance for the wisdom.

 

[steve murdoch]

Do you hear a clunking noise just before the starter clutch is engaged?
http://www.thegsresources.com/_forum/showthread.php?67561-How-does-a-starter-clutch-work

If it is just a matter of not spinning fast enough it could be something simpler like your battery.

Welcome to the site.

 

[dahlstrom]

Hey Steve, thanks for that link. No clunking noise at all here. Reading the post, I'm realizing that the large gear behind the clutch isn't touching the clutch at all! It's a good 1/2-3/4in separated from the clutch so it makes sense nothing else is spinning. So I wonder if something's not on there right.

I also just compared the setup on the bike to an extra rotor, clutch and gear setup I've got and the three clutch screws are definitely missing on the bike. So now I'm down to the question of how I get this rotor off because it will not budge.

 

[hillsy]

So the starter motor is turning...the gear behind the rotor is turning...but the crank isn't?

Then you have a problem with the starter clutch....either the rollers are not engaging or it has been assembled incorrectly.

 

[Guest]

Here is what you need to get the rotor off the crank. Remove the factory bolt then turn this one in. http://www.ebay.com/itm/Motion-Pro-...404486?hash=item360d5c9206:g:nLEAAOSw44BYNSZT
Get it started by hand then switch to an impact gun. I'm having the same problem with Red, my 1100E. The srews backed out the sheared off and after replacing them I got about 15 starts then it starts slipping. I looked at the rollers and they were round, so I'm thinking my springs got weak. I've had bikes at work where the rollers flat spotted and wouldn't grab the crank any more, but these looked perfect.

 

[hillsy]

Rick - the ramps the rollers engage on will develop flat spots as well as the rollers themselves. We used to use a die grinder to smooth out the ramps when I worked in the shop some years back.

 

[tom203]

"The starter motor actually is working fine, it whirs and turns like it should, and spins the bigger gear that's right behind"

is it whirring in right direction? Looking at layout on left side of bike, the starter motor should spin counterclockwise as you face it .

 

[dahlstrom]

If I'm remembering right, it is turning the right direction. I'll check it again this evening.

Thanks for the link, Rick - is the tool something that you just screw in partly and smack with a hammer? Or is the rotor supposed to come off once it's screwed in a ways?

 

[dahlstrom]

Well, the bolt from ebay didn't work....it's too big. Has anyone removed the rotor for this year and model specifically? Having a hard time believing that this one motorcycle needs something so specific, but maybe I'm waking up to the reality of owning one of these babies.