Replacing clutch shaft...

J

Jeckler

New Member
So I managed to strip the threads on the sprocket side of the clutch shaft yesterday, so I started tearing it down for replacement. It's a good thing I stripped the gear puller trying to remove the clutch hub though, as it gave me time to do some research and find out the case doesn't have to be split to replace the shaft.
I removed it by tapping from the sprocket side, clutch hub and all. Stripped it all down and I need a new shaft and at least one bearing. The shield popped out and I'd rather replace it, as it's only a couple bucks.
Anyway, the shaft itself. Mine has halfmoon keys, and the slots do not extend into the threaded portions of the shaft. Now, I don't know if it's just the pictures, but both Pistonbikes and Gasbike show a shaft that looks like it takes a flat key with rounded ends and the slots extend into the threaded portion. I'm going to guess that these keys are not full length and I can still tighten a nut as needed.

Questions:
Do I spend the $6 on the flat keys.
Since I'm running a 415h chain, do I splurge on the 415 sprocket that Gasbikes has?
Since this area is separate from the engine itself, I assume shielded bearings like stock are OK. IOW, Rubber sealed is unnecessary.
I should be able to use the stock washers and nuts to secure the hub and sprocket, right?
 

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I replaced my clutch shaft with a pre-assembled shaft from gasbike and didn't notice the spot on it for the flat keys. I would suggest you spend a couple more dollars and buy the pre-assembled shaft that way you don't have to worry about putting it back together with the proper torque on the spring.

I re-did mine with stock hardware and everything even though under my circumstances I should have replaced the sprocket and nut on that side. But months and a bunch of miles later it hasn't budged.
 
So it used the half moon keys?
The picture they show for the whole assembly shows the same style key as the pic I posted above. Apparently I need to call them, because I'm also worried that if it is this other style that uses the flat key, are they the same width so my clutch hub and sprocket fit.
 
To attach the sprocket and the clutch wheel it uses "semi-circular bonds" aka, half moon keys. Those keep the sprocket and clutch wheel from moving. You should have a pair if you already took your clutch shaft out.

I don't feel like trying to find my old one, I will if necessary, but I don't remember anything being inside the spring on the shaft.
 
Look closer at the pics I posted and you'll see what I'm talking about. I'm not talking about the spring at all. I'm referencing the two slots near the ends. My shaft and apparently the one you have use half moons for the hub and sprocket. The pic I posted of the replacement shaft shows a different style of slot, which uses flat keys instead.
 
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Nope. It uses half-moon keys. I'm sure of it. I can see it in the first picture and the one from gasbike is the shaft I bought over a year ago.
 
OK, first of they called "woodruff" keys and A LOT of the engines out there have up to three different size woodruff keys . YOUR CHEAPEST AND FASTEST BET is order from BGF off e-bay. You should search norm's repairs and you find how to set up a complete clutch shaft . Youcan even modify the tension on the spring to get it set up more for race . Man it will reallllllyyyyyy grab A$$ and $hit and get. If you do the search you'll learn from the best . Not some guy hopped up on cactus juice . LOL
 
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Has anyone ever posted the size of the Woodruff Keys? I need to replace one and 3.99 plus shipping for one seems a little ridiculous when I can get a set of keys from Harbor Freight for around $10... I just need to know what size. And no amount of searching I've done gives me a clue...
 
Do you have vernier calipers. You can measure it, the slot. The woodruff key fits inside the two slots, bring your shaft to a ACE Hardware. My Ace has a section with all the fittings and screws. Somwheres is a case called Woodruff keys. Its flat on top and rounded on bottom. it sets so the front pushes down and the back raises when you push on the sprocket and clutch assembly on shaft. The back end catches the slot in the two aforementioned parts and locks them

If you have a bench grinder you can grind a larger one down to fit.

ACE is the place for the helpful hardware MAN!!! But the chicks who work there are hot!!
 
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