2011 TE-310 Sheared Keys & Non-Start

You don't want anything compromizing the sleeve retaining compound, or on the mating crank shaft/flywheel surfaces. Oil, grease, powders, dirt, etc.... Fingers and hands transmit oil from your skin.

It has to make a clean contact between both surfaces for perfect bond. I'm pretty sure I only went 10 ft lbs over manual specs for flywheel nut. Don't think it really mattered on the 10 ft lbs over but in past threads. Seemed like everyone else was doing it.

no, no... I get that (although I think clean hands are fine); I don't understand the "latex" thing.

Some of them gloves have a powder on them. Some, when you put them on, they disintegrate when you wipe them off with carb cleaner, acetone, other chem.
But try sticking your finger with rubber glove in the flywheel opening taper with rubber glove.
So, I'll just recommend the carcinogen way. Just use carb cleaner and clean heck out of your fingers, to smear the sleeve retainer compound on the crank and inside flywheel. Just nice thin coating.

OK the key was sheared...of course it was. straight edge is still in flywheel and the curved edge still in crank slot. crank is a little boogered up so I am going to lap it and do as said in this thread. Will be using brake cleaner to clean everything off - dont want to get the cleaner inside the case but will clean it with cleaner with shop towels. I am going to attach a pic as there is a part which I am not sure the name of, I would call it some sort of retainer clip. This clip sits on the bottom side of the flywheel seems to retain the sprag - and it does not spin freely, in fact, it spins and then it hangs...then spins as you rotate. The four arms seems to a little off as they ride around in the groove the of flywheel. I am not sure if this should snap on and rotate completely freely but I can't imagine this being right given the rpm's this thing spins at.

At this point, I am going to pop the pieces of the sheared key out and then begin lapping and cleaning the crank and the flywheel.

(waiting for srowzeen's post)

I don't know what happened, the last post I did, didn't stick. So I pulled the flywheel and the key is sheared. Everyone's suspicion was confirmed. This is the third key. We can't ride this bike for 10 mins that it doesn't shear the key. The nut was not loose but it was not tight either. I pulled the flywheel off and I have to admit, this flywheel appears damaged. It has heat discoloration, it is pitted on the inside surfaces of the cup side. The sprag side is in bad shape too. The retainer clip actually isn't even clipping on the flywheel and it appears the sprag is working free from the flywheel. It snaps in place and the retainer clip snaps over it. However - that retention ring doesn't snap and is super loose. The surfaces of the flywheel are a mess. The only surface that seems OK, is the inside mating surface to the shaft, but you can tell it needs some lapping. This all said, the flywheel looks like it has been over heated, dropped on a gravel path, kicked and the retention ring doesn't snap to the flywheel. It doesn't seem too far-fetched that this flywheel is a problem.
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sorry about the double post

Like I said when my key sheared I threw my flywheel away.
I had an extra in a parts box.
They are not cheap though.
Be prepared to spend a few hundred for a flywheel, sprag and key.
How is the ring gear?
How many hours on the bike?

OTOH, if the E-start was working okay just clean it up and reuse. Really, it does not look that bad from the pic.

BTW, you can always pull the spraq and ring gear out and loose the E-start and just kick it to start.
The E-start on these bikes is a bit under engineered for long term use anyway. I rarely use mine. You can even take the starter motor off and plug the hole in the case with the cover from a TC250.
Eventually the gears wear and the sprag fails, welding itself to the flywheel and ring gear necessitating replacement.
i have one so welded that I cant get it apart with presses, levers or heat. It's stuck!

What you need to do is clean up that crank, just enough to get the burrs off.
You don't want to have to replace that crank.

Buy something called "Prussian Blue". It's a blue dye that will tell you the high and low spots.
Medium valve lapping compound and Loctite 609 retaining compound.

Be very careful. If you take too much off you will need to replace that crank.

Got a pic of the crank end?

That sprag retainer is not supposed to spin.

You can just bend the "ears" to make it fit tighter.

I agree 100% with R_Little's post, including the removal of the sprag/electric start "IF" you have to.

I will add: go easy on the silicone gasket stuff. a tiny bit is okay, but don't let it goop up.

OTOH, now's a good time to goop up your rubber grommet that carry your stator/ignition wires into the case. famous for leaking here.

So, thank you both for your help - it is so much easier to get input and methodically go about this than to jump and shotgun it. Here is where I am - flywheel is on order with Dan at Motoxotica in Vacaville - he has been super helpful. Sprag is brand new and in great shape no need to replace it. Needle bearing or roller bearing which is inside the freewheel (starter gear) is brand new too as is the freewheel. So not replacing either of them. I used medium valve lapping compound on the crank. I had taken a black sharpie and did a cross hatch design around the crank to give me a good idea of what I needed to take off and smooth out. It worked out great. I am going to begin using super fine 600+ emory paper to make the crank shine and baby butt smooth. I will be very careful to not overdue the polishing so I am not removing material. The sprag retainer ring is a mess whether it is suppose to spin or be a snap on and be stationary. It doesn't snap on, and have tried bending the arms to make it snap on, but it is a bent piece of metal and likely never to return to its former glory - it needs to be replaced. I will take a pic of the crank when home.

TRENCH - you mention silicone gasket stuff - you are talking about the goo for the stator wiring correct? That whole design is jenky, but will check it to make sure it is sealed off.

R_Little - abandoning the whole electric start might be my last and next step. Do we know for sure the keyway is aligned to TDC... no matter how often we shear a key? Also, the bike has 2650 miles on it...

I am still lost as to WHY I continue to shear the key - what is the main cause? nut comes loose, electric start does what to the union to the flywheel and the freewheel causing it to shear?

I am thinking Assembly error, resulting in conical joint that doesn't carry load it supposed to. If interested Search Google for conical/bolted joint combination to understand how both supposed to work together. I think I have seen couple of white papers floating in cyberspace

My problem with sheared key started on bouth of my 310 about 100 hours of riding. the first bike i used about 3 keys until I sorted out the problem,
and to me the problem was that the torque figs from the workshop is 75nm and that is way to soft. I tried 2 or 3 different until I came to 100nm and now
it dosen't brake any more. I haven't had any problems with the 250 bike and it has 375 houres now.
I think that the problems starts after some riding due to the bike "pops" it is an enormous force on the key.

I would guess the problem is the taper; the key is just for alignment in most applications.
[later edit: I have update my thinking (I'm blaming the worm starter drive mostly now) in a new thread: http://www.cafehusky.com/threads/sh...-electric-starting-a-few-long-thoughts.87927/

]

Also, i would not dress the crank without using the flywheel. You want them mated, not just smooth.

Is your original flywheel that messed up that you couldn't reuse it? ...and how much is a new one?

The goop problem is that your case surfaces look like they had excessive silicone gasket maker on. IMO, this stuff can cause way more serious problems than it solves (fragments from "gooping" end up in the engine, clogging small oil ports). On a clean gasket, I will sometimes spread a thin-thin layer over the entire gasket- making the gasket look a bit shiny. Most of the time though, I don't do this. I would use black silicone on the wire grommet, especially the edges.

good luck.

So my flywheel is not going to be here until Wednesday. Will install then...

TRENCH you ask could I not reuse the flywheel. I am going to attach photos for you all to look at, but honestly, here are my observations. Inside is pitted heavily. Inside is super discolored from high heat. There are nicks and dings all over it. I feel like it is likely loose and not in spec any more since it is so incredibly discolored from heat. Maybe I am being overly cautious, but at least the guts of this thing is going to brand new. Also would love some input on the stator and any other observations.

clean out those metal fragments behind the worm gear, of course. Are those steel or aluminum chips? seems like a lot if it's steel... and from where? Spray wd-40 to flush 'em out, if brake cleaner is not your thing.

your wire grommet has been "gooped" already; the job looks good and oil free.

Your flywheel/discoloration looks okay to me (I've never had my flywheel off though). The keyway seems undamaged. I cannot see the dings/pits but I'll take your word for it. BTW, I can see the pics close-up better on my 5" phone screen than this 23" computer screen I'm using... unless I take the images into an editor. irritating. wait... I just enlarged the image- are you talking about the mating surface (looks ok I guess) or the stuff outside that (not any major issue or balance problems as far as I can see)?

The crank concerns me slightly (just slightly)- I'm not sure about that inboard ridge, and the surface of the taper looks overly worked or something. Anybody with experience got an opinion? Also- the crank portion of the half-moon key is stuck on the flywheel.... so I'm guessing that my steel chips are the other key half maybe? I can't imagine the crank/flywheel spinning enough, but do you think that's where the "over worked" look the crank has is from?

Correct, Remove any big burrs you can see but DON'T polish the crank end, Just put some valve lapping compound on the crank end and spin the flywheel W/O the key until it gets scuffed up. You want it like 200 finish so that it grips when installed. Polished means slippery and slippery is a no/no. Don't press too hard either.

You key shears because the crank / flywheel fit is messed up. I am hoping that the problem is just a couple of burrs on the flywheel causing the poor fit. If you got the big stuff off them just hit it the lapping compound a little. The taper holds the crank. The key is just for alignment.

You really should use the "Prussian Blue" to check fit.

How much was your flywheel?

You don't want to wear it so much that it causes a ridge on the inside of the crank end. the flywheel will butt against that ridge and that will cause a fitment problem as well.

Of course you will not spin flywheel while lapping, make back and forth short irregular oscillating motions around key grove. Also move back an forth on occasions to alow for cutting media to spread randomly. Fit of the woodruff key is also important and tolerance is specified.
After final assembly mount dial indicator and check both flywheel face and outside surface for excessive movement.

I think you have more problems with your engine. Your starter gear is probably worn and thats why you have metalfragment there.
If you look at the picture you can see my mark and thats probably a crak in the starter, that soon can resolve in pulled starter that will take a piece of the engine block to.