Starter Clutch and Crank Question '80 GS1100

[Kaiser Sosei]

The other day I stopped for gas and when I pushed the starter button, the starter spun but the crank didn't. I figured the starter clutch crapped out, so I push started the bike and rode back home about a mile.


I pulled it apart tonight and here is what I found:

When I pulled off the stator cover the three screws holding the stator onto the cover had backed out and one of them got bent pretty bad.

The nut holding on the flywheel was fairly lose, and took very little effort to undo. The flywheel practically fell off as I was removing the nut. So much for waiting for the special tool.

The tapered end of the crank has some fairly deep gouges in it. The flywheel has similar marks in the tapered area as well.

The starter clutch bolts are still tight and it appears to be funtioning, as it free wheels in one direction and grabs when I spin it the other direction.



Question 1: Any way to test the starter clutch? I'd like to confirm that it is good before I put it back together. I was thinking about just getting new springs and rollers but I haven't gotten it apart yet to check the rest of it.


Question 2: Is it common for the taperd end of the crank to have gouges in them? I'll try and get some pictures later tonight and upload them, but a couple measure around 0.015 inches. Wife has the camera. They look like they could be casting imperfections, but I'm not sure how the cranks are made.

Sorry for no pictures at this time, but just wanted to get the conversation started.

 

[blowerbike]

this is almost the worst thing that could happen in that area.
to fix it correctly you need to have a new left side put on the crank and purchase a new alt. rotor.
the worst thing that could have happened is the crank snout breaking off at the main bearing...bad is bad though.
get a good alt. rotor and cover the crank taper in red locktite(or use your existing rotor just to keep it cheap for now) and impact its bag off during reassembly.
be careful during your 1st start-up cause if the rotor pulls to far inwards from the crank snout being smaller(shrunken)...the whole assembly could lock up and act like direct drive and spin the guts out of your starter.
as far as the starter clutch...thats the least of your worries.
if everything looks ok just install 3 new allen bolts if there damaged(flat threads) and put it back together.
your working with a major part thats damaged beyond repair....don't sink a lot of money into it as you may end up swapping engines.
FYI
80-82 1100's and 82-83 1000/1100 kats have the same evil small tapered cranks.
83 black engine or any 1150 engine is a bolt in and 100% stronger in many areas.
just to mention this again...
DO NOT throw much money into this engine...try it the cheapest way and maybe you can get a few more miles out of what you have.
good luck.

 

[Kaiser Sosei]

So basically I'm trying to "weld" the rotor to the crank with the red locktite.

Understood.


Weird that it gave no indications of this happening, it just broke loose and wouldn't spin the crank. Anything special about the 3 crews that hold on the stator or can I just go grab some new ones from the hardware store? Will socket head work or are they to tall?

I won't bother taking off the starter clutch, seems like there's no point. Everything looks good except the crank and the busted staor screws.

Here's a pic of the crank.

edit to add, the blueing looks a lot worse in the picture. I thinks its the flouresent lighting in the garage.

 

[TeamDar]

I have good rotors with starter clutches for sale for $65 shipped. These are listed in the parts for sale thread. Dar

 

[sparki]

i've had worse crank ends than that that are still working after an additional 10000 miles.

those marks aren't great but.... what i did was get a little valve grinding paste ond pop it on the crank end..... use the alternator to work out any high spots (don't do this too much however as the further onto the crank the alternator goes the more you risk the starter clutch locking up). just enough to get rid of the high spots. clean thoroughly. like has been mentioned; be liberal with RED loctite and use an air gun to tighten up the nut. test n ride again

oh.... and def replace the starter clutch allen bolts while it's apart... blue loctite em in and use the correct torque plus a little more

 

[blowerbike]

I have good rotors with starter clutches for sale for $65 shipped. These are listed in the parts for sale thread. Dar

damn!
i sold every rotor and SC i had in 2 years time...
and........
for a lot more than dr. dar wants.
maybe i need to re-stock:-k
hell of a deal!

FYI folks.
the small and big left side engines use the same starter clutch housing except for shafties and maybe the 82/83 kats.

 

[blowerbike]

hey OP...
red locktite the crank nut also...can't hurt anything.
i forgot to mention....
if your on again/off gain on the throttle a lot or like to run the revs up and wack the throttle closed..
none of the above mentioned fixes will do you any good.
also down shifting aggressively will knock it loose again.
just the fact for the small taper big CC cranks.

 

[Guest]

You will want to use grade 12.9 allen heads to secure the starter clutch to the rotor

 

[Kaiser Sosei]

I have good rotors with starter clutches for sale for $65 shipped. These are listed in the parts for sale thread. Dar

Thanks for the offer, but I think the starter clutch is good. Bolts are still on tight and appears to be working. I'll take another look at the rotor, but I think it will work as well.

i've had worse crank ends than that that are still working after an additional 10000 miles.

those marks aren't great but.... what i did was get a little valve grinding paste ond pop it on the crank end..... use the alternator to work out any high spots (don't do this too much however as the further onto the crank the alternator goes the more you risk the starter clutch locking up). just enough to get rid of the high spots. clean thoroughly. like has been mentioned; be liberal with RED loctite and use an air gun to tighten up the nut. test n ride again

oh.... and def replace the starter clutch allen bolts while it's apart... blue loctite em in and use the correct torque plus a little more

I'll try and grab some lapping compound today. Wife works and I have the little ones with me, might have to wait.

hey OP...
red locktite the crank nut also...can't hurt anything.
i forgot to mention....
if your on again/off gain on the throttle a lot or like to run the revs up and wack the throttle closed..
none of the above mentioned fixes will do you any good.
also down shifting aggressively will knock it loose again.
just the fact for the small taper big CC cranks.

Planned on doing the nut as well. Like you siad, can't hurt. Good advice on throttle. The bike is mostly a commuter vehicle for me, at this point I'm just hoping it lasts until we pay off the minivan and I can start looking at new bikes. I've already been given the green light. It's just hard to justify a new bike for what amounts to 30 days a week. That's what I liked about my GS, paid for and cheap to run.

 

[Kaiser Sosei]

You will want to use grade 12.9 allen heads to secure the starter clutch to the rotor

Starter clutch bolt are still on tight, I can get them off as I don't have anything to clamp the rotor down with, and I can't hold on tight enough.

I need to replace the Stator bolts and was wondering if there is anything special about them or can I just go down to the hardware store and replace them?


Edit to add: I was thinking about filling in the gouges with some JB weld just to give a little more surface area for the locktite to grab onto. Worth it or waste of time?

 

[blowerbike]

i would pass on the JB...you want the rotor to bond to the crank not the JB.
lap if you like but the red locktite is the key.
let it set up over night also.
stator screws are just screws...use what you want as long as there is running clearance with the rotor.

 

[Kaiser Sosei]

Thanks for the info. We'll see how it goes. Hopefuly I have time today when the kids are napping.

 

[Kaiser Sosei]

I was able to perform the procedure yesterday and went to investigate today after the locktiite had time to cure. Is is possible to tighten the nut on the crank too much? The gear for the starter clutch doesn't spin freely. If I take a screwdriver and work the gear in either direction, the crank turns. If I wedge the screwdriver to stop the gear, I can turn the crank and the gear doesn't move, so I don't think it's too much locktite. I'm thinking the rotor is pushed in too far, but I'm not sure how freely the gear should be able to move. Will it loosen up once it gets some oil in there, I installed it dry to ensure no contamination of the locktite. Prior to installation the starter clutch gear would lock up properly in one direction and was fairly easy to spin freely the other.

Am I proper ****ed?

 

[blowerbike]

"be careful during your 1st start-up cause if the rotor pulls to far inwards from the crank snout being smaller(shrunken)...the whole assembly could lock up and act like direct drive and spin the guts out of your starter."


that is part of my 1st comment on page one on this topic.
are you sure that you didn't get locktite on anything other than the (taper)?
did you re-install the brass thrust washer that sits against the main bearing?

 

[Kaiser Sosei]

"be careful during your 1st start-up cause if the rotor pulls to far inwards from the crank snout being smaller(shrunken)...the whole assembly could lock up and act like direct drive and spin the guts out of your starter."?

This is what I'm afraid of. So I'm wondering if the starter gear should move more freely. I suspect the rotor got pushed in to far by over tightening.

are you sure that you didn't get locktite on anything other than the (taper)?

Yes, I only put the locktite on the taper and left about 1/4" dry near the fatter end of the taper to make sure no locktite got squeezed into the bearings.

did you re-install the brass thrust washer that sits against the main bearing?

Yep, it was the first thing I made sure was put on so I wouldn't have everything installed and find it on the workbench.

I think I will be taking it apart and trying again, being more cautious of how tight the nut gets.


Will a heat gun or a propane torch get it hot enough to break the locktite, or do I need to go out and get some MAPP gas?

 

[blowerbike]

that nut has to be super tight or it(rotor) will spin right off.
the problem is your crank snout is now smaller and your rotor is now larger in the bore.
if this is the case you might grab a rotor s/c from dar for cheap and re-do what you have already done.

 

[blowerbike]

propane is fine but just use your new puller.

 

[Kaiser Sosei]

Took it apart this morning and everything look OK, doesn't look like I bent/torqued anything out of shape. I put everything back together and hand tightened up the nut on the crank as much as I could with a breaker bar. Gear spins freely and the rotor doesn't spin loosely, so I think I will give it another shot tommorrow this time making sure not to over tighten it. Tightening it up as much as I can with the impact, but still letting the gear spin.

 

[Kaiser Sosei]

Got it back together yesterday and took her to work today. So far so good. We shall see how long this repair will last. There was definately a fine line between tight enough and too tight. Thanks for the help guys.

 

[blowerbike]

if it wasn't damaged...
there is no way to over tighten it.
keep us posted.