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Discussion Starter #1
So my 660 grizzly wet clutch gave it up. Bought the bike with a clutch kit already installed, wet clutch has the higher stall springs in it but not sure.if they're 500rpm or 1000rpm.

Anyway, local dealer wanted a lot of money, so I went online and bought the Niche brand from Parts Discounters. Couldn't find much info about their clutch parts but the HD axles had great reviews, so I figured I'd try it.

Got it back together and wow, does it feel healthy compared to before. I also ordered a clutch slug kit from Hunterworks and it unfortunately didn't get here in time for me to install. Friend from out of town is here to go riding this weekend and I only see the guy once a year if I'm lucky. The guys at Hunterworks were great, Canada post however drug their feet and well, here I am. My plan now is to put a few hundred kilometers on this new Niche wet clutch assembly and see how it is. I have a 686 BBK sitting on the shelf for November when I can afford the downtime. When I do the big bore I'll also pull the wet clutch and install the slugs, and report back to let everybody know how the niche clutch is holding up.

Install was straightforward, oem bearings and seals were used with the niche clutch and drum. Any questions feel free to ask.





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Make sure to throw away those stall springs with the old wet clutch assembly. They are the reason why the clutch failed in the first place.

Looking forward to hearing about the long term updates of this Niche wet clutch.
 
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dezz is right on!

Notice the worn tips on the old blocks? Because the stall springs hold the blocks back until the engine is 500/1000 rpms up its torque curve, the block tip touches the drum at much too high an rpm/torque, and wears the friction material right off the tip...

The factory clutch carrier, (blocks and springs) were designed to work together, to gently engage and begin to turn the clutch drum, waaay down low on the torque curve, a bit over idle speed.

walt
 

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Discussion Starter #4
I am not reusing the stall springs. I think that short term, for some riders they might be the answer for their but dyno, but long term cause more harm than good.

That said, I already like it more and I've only ridden around the block twice.

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Discussion Starter #5
So, clutch worked too well. I shredded the left rear axle and had to ride about 20 kms back to the truck. The rear diff ended up getting torqued to one side and ripped up three of the diff mounts.

So today was a lot of welding, bending cutting and cursing.

Also installed the rear two HD niche axles that have been on my workbench for three weeks. Lol. Also flipped the rear hubs because the 28s hit the rear plastics. Alot. And I've cut them back further than I wanted to already.



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So, clutch worked too well. I shredded the left rear axle and had to ride about 20 kms back to the truck. The rear diff ended up getting torqued to one side and ripped up three of the diff mounts.

So today was a lot of welding, bending cutting and cursing.

Also installed the rear two HD niche axles that have been on my workbench for three weeks. Lol. Also flipped the rear hubs because the 28s hit the rear plastics. Alot. And I've cut them back further than I wanted to already.



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That's some dang nice carnage there bud. I'm used to seeing my buddies Popo spit out diffs but I think this one takes the win. Hope you get back on the trail soon :/
 

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Breaking rear diff mounts is a known issue on the Grizzly 660. Most catch it being loose in the frame before it rips the mounting tabs from the frame. Making a diff brace fixes the issue. Looks like you did just that.
 

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Discussion Starter #8
Yeah, I caught the loose diff bolts after my last ride and tightened them up. The trashed axle and 28x12 tires for a 20 kilometer ride is what finished my mounts. Oh well, it's all beefed up now lol.

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Discussion Starter #9
About 300 kms on the niche wet clutch. No noticeable wear. Keep in mind I have big heavy 28x12s on all 4 corners.of this, and I'm 6'1" 265lbs. I tore it down to finally install the clutch slugs I got from Hunterworks. Fit like a charm.


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Good to hear.
It’s nice to have options other than factory over priced stuff.
You’ll like the slugs.
It totally changed my grizzly. So easy to creep around with now.


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Discussion Starter #11
Good to hear, the slugs have been on my toolbox since august. They arrived after the rest of the parts and I had friends from out of town that planned a ride, so I decided to do a before and after.

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Just finished mine, I will have to check my bolts before I ride it. Mine looked worse than that, had to get new housing also.
 

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Discussion Starter #13
Wow, I didn't know they could get worse lol. Mine wouldn't move under its own power anymore. I guess it could have been partly due to the stall springs. I'd like to see a picture of yours too.

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