I’m a bit confused by this. I was reading up about how woodruff keys work, including https://www.huyett.com/blog/woodruff-keysI’m not sure if you checked it already, but as L.A.B. mentioned earlier, I would definitely check that when installed, the woodruff key is not taller than the keyway, as that would obviously stop the sprocket seating properly on the taper
Yes, I think he is referring to the keyway in the pulley. If the key is too tall, it won't pull down tight on the taper.I’m a bit confused by this. I was reading up about how woodruff keys work, including https://www.huyett.com/blog/woodruff-keys
So isn’t the flat part of the key supposed to stick out of the keyway a little?
Thanks for this. I’ll try to find the correct o ring here in the UK.A nonstock mod I would recommend since it is apart is, the small oring over the crank against the seal.
This helps seal the crankcase better.
Here's the write up, from Mr. Schmidt, Jseng1.
The only real (very rare) problem wet sumping can cause is blowing out the crank main seal. You can avoid that problem by installing a 1-1/8" ID 3/32 wall viton oring between the primary sprocket and the main seal. Its a #122 oring and you can get them for cheap at suppliers like Mcmaster Carr. Wet sumping also makes it a little harder to kick over the motor but its not much of a problem on kirk start 750s or 850 Mk3s with electric start.
Along with the o ring, I would replace the crank seal... Just because.... after the little sanding/polish recommended by Mr. Marsh.
Yes, that’s correct, however if the incorrect key has been fitted and it protrudes too much from the shaft it will not allow the pulley to fully seat on the taper (which is imperative). It may be fine, but as you already have it apart it’s worth checking. You can probably just use a vernier to measure how far above the taper it protrudes when set parallel and then compare that to the depth of the groove in the sprocket. I hope that makes sense.I’m a bit confused by this. I was reading up about how woodruff keys work, including https://www.huyett.com/blog/woodruff-keys
So isn’t the flat part of the key supposed to stick out of the keyway a little?
Sorry if I’m being dumb here
New keys are on the order. Hopefully the keyways are OK.You have to assume all the woodruff keys on the primary side are botched, so buy all new keys from a Norton supplier and that should remove doubt. You are left with the key ways being the wrong size by previous use of loctite or burrs.
I think I've found a supplier for the mod o ring. Do you think the durometer rating matters? 70, 75 or 90 ShA are the optionsA nonstock mod I would recommend since it is apart is, the small oring over the crank against the seal.
This helps seal the crankcase better.
Here's the write up, from Mr. Schmidt, Jseng1.
The only real (very rare) problem wet sumping can cause is blowing out the crank main seal. You can avoid that problem by installing a 1-1/8" ID 3/32 wall viton oring between the primary sprocket and the main seal. Its a #122 oring and you can get them for cheap at suppliers like Mcmaster Carr. Wet sumping also makes it a little harder to kick over the motor but its not much of a problem on kirk start 750s or 850 Mk3s with electric start.
Along with the o ring, I would replace the crank seal... Just because.... after the little sanding/polish recommended by Mr. Marsh.
No, just needs to be resistant to hot oil. So just get the rating easiest to obtain.Do you think the durometer rating matters?
What Kommando said above. Oil and heat resistant.I think I've found a supplier for the mod o ring. Do you think the durometer rating matters? 70, 75 or 90 ShA are the options
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Really good idea, just don't let the earlier stuff confuse you since we had not determined the problem yet.Yep - parts have now arrived. I'll be making a start this afternoon.
I'm going to re-read the entire thread, make notes and take my time