1,000ft

[1nc 2000]

Never heard of a spiders cracking, thats a new one to me and not sure how that could even happen, but certainly down low on the sheaves for cracks from heat. Also buttons being tight on the towers, but certainly groves being worn on the faces. Bushings are going to need clearance for movement, but if the clutch looks good on the faces it should be a decent enough low mileage clutch.

I broke 2 spiders over the years in my FX nytro.
First one all stock clutching.
Second one with Ulmer full clutch kit.
Both with 8dn belt.

 

[KnappAttack]

So does anyone have photos of a broken Yamaha spider? I've never seen such a thing and can't imagine why one would break. Hearing this makes me never want to run a Yamaha primary ever again if they are weak enough to just break on a wimpy Nytro.

 

[1nc 2000]

Here is a couple pics of the last spider that broke on the nytro.

 

[Fleecer]

Here is a couple pics of the last spider that broke on the nytro.View attachment 179837View attachment 179838

Looks like the damage was as caused by a weight malfunction?

 

[74Nitro]

The ones I have seen and witnessed cracked from the inside out. Where the aluminum molds to the steel.
I don't have any pics, this was many years ago.
I recall asking my dealer if he had ever seen this happen, he said a few, but it's a rare occurance.
The first sign is the machine will rev much higher as the crack causes the spider to bind.

 

[1nc 2000]

Looks like the damage was as caused by a weight malfunction?

The weight and roller were fine. They went into the next clutch and am still running them today.

 

[74Nitro]

The weight and roller were fine. They went into the next clutch and am still running them today.

Ok, so not seen in the pic is that there's a crack that started down lower on the spider and made its way up to the roller?
This is what mine did also.

 

[1nc 2000]

Ok, so not seen in the pic is that there's a crack that started down lower on the spider and made its way up to the roller?
This is what mine did also.

Yes

That Nytro had the 5 year YES warranty on it. I exceeded the price of the sled in warranty claims and the YES warranty became void when that happened.

When the clutches would get dirty the 8dn belt would slip on top end and create heat in the clutch. I had to clean the faces on clutch every 300 miles otherwise rpm's would climb up and hit rev limiter.
Belt life was around 2000 miles.

 

[Doc Harley]

Are there any inherent differences between an RX1 primary & Apex primary? I have a chance to get one or the other.

 

[sideshowBob]

As far as I am aware...the RX1 and early Apex primary clutches with the set screws are the same.

 

[Doc Harley]

As far as I am aware...the RX1 and early Apex primary clutches with the set screws are the same.

Ok, thank you

 

[KnappAttack]

I've never seen a spider break like this before, thats crazy. I doubt highly its heat related as its not connected to the sheaves in any way and gets plenty of cooling from windage.

I've run my 1000 mile RX-1 primary for many miles on 300+ HP Winder for a few seasons prior to going to the TAPP I ran without any issues. Also have run the Yamaha primaries on turbo RX-1 and Apex for many miles. Guys have even run the Yamaha primaries on turbo 1200 Doos which were extremely hard on clutches and I've never seen such a thing. Don't know how a low HP Nytro, could break this spider, just doesn't make sense to me. Typically heat would crack the sheaves down at the post area from engagement and slipping down low like the Cat TEAM primary would see.

 

[fatchance]

Seems to me the movable must have been binding and caused the spider to lock up and snap the tip of the arm off when the weight swung. Just a thought.

 

[journeyman]

My high mileage 2007 Attak GT that I bought from Kip up at Pat’s had a groove in the faces from the guy riding it easy at 50-60 mph with his wife. I brought the clutch to work and my machinist buddy refaced them on the lathe. It actually grabs the belt much better than a stock clutch to this day. If I ever get rid of that sled I think I will get another YXR primary and put it on there and keep this clutch.

 

[Doc Harley]

My high mileage 2007 Attak GT that I bought from Kip up at Pat’s had a groove in the faces from the guy riding it easy at 50-60 mph with his wife. I brought the clutch to work and my machinist buddy refaced them on the lathe. It actually grabs the belt much better than a stock clutch to this day. If I ever get rid of that sled I think I will get another YXR primary and put it on there and keep this clutch.

I did some reading up on refacing the surface. It's not really recommended. I assume even a light resurfacing will change the spring rates throughout the range. Perhaps a washer in the spring cup could help to correct this. Idk....I sure wish it was that easy.