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Offset wrong under load? Video

I think there should be a poll.....how many belts blown with STOCK clutching VS how many without stock.

The guys running closer to stock clutching seem to do better....

Im getting closer to stock now, and seeing less and less heat.....

You guys need to remember stock primary spring is a LIGHT finish rate.

But I think SOUPY has something else going on.

I would like to add,,, belt adjuster or no belt adjuster to this poll. Seeing a pattern here myself.
 

I was on lake wide open in about a foot of powder 20 seconds later boom
 
I would like to add,,, belt adjuster or no belt adjuster to this poll. Seeing a pattern here myself.
Some belt adjusters will allow for MORE belt float, but only outward. While the OSP I designed only allows for stock amt of belt float. I dont see this as an issue with my BOP(with alot more float) as the secondary never seems to even try to float out.

I had this theory of it floating out of whack too much on decel then when we whack it, we blow belt...but I have never been able to replicate that, so I dont think it happens.

Dan
 
I just wish we had a belt that was designed for 200+hp and not 135.

Not saying that is issue, but with these heavier driven springs, and all this HP we are just pulling these belts apart. They just cant take the big power very long. YAM stock setup is SOFT drive and SOFT driven, most of us are changing those characteristics and belts start to blow.

Dan
 
Mine blew when slipping in powder and catching tracks on lake....seems like this is when you need to really be easy on things, I was only going along half throttle and mine went into pieces then.
I wasn't even at half when mine went. I was running a 280 Race Hurricane tune.

Don't get me wrong the high heat and shredding belts would be very frustrating but to think we are going to take a 200 hp sled and run them at 270+ and not have a few belt issues isn't being very honest with ourselves.
 
I wasn't even at half when mine went. I was running a 280 Race Hurricane tune.

Don't get me wrong the high heat and shredding belts would be very frustrating but to think we are going to take a 200 hp sled and run them at 270+ and not have a few belt issues isn't being very honest with ourselves.
I hear that.....at least the cat in 12 had a belt made for turbo power and heat.

Now all we get from YAM is a belt designed for 135hp viper NA. grrrr

I often think this is why CAT 998 has less belts blowing, just cause the have a better belt period. Checked specs, not close enough to make a cat belt fit to test either.

My ultimax snapped, but remained one long piece...the 8JP went into tiny pieces pretty much.
 
I just wish we had a belt that was designed for 200+hp and not 135.

Not saying that is issue, but with these heavier driven springs, and all this HP we are just pulling these belts apart. They just cant take the big power very long. YAM stock setup is SOFT drive and SOFT driven, most of us are changing those characteristics and belts start to blow.

Dan

I think you are on to something AND it sure seems staying as close as possible to the stock clutching setup adjusted for power is easiest on the belt...draw you own conclusions here...but I have tested with aggressive stuff and closer to stock stuff and to me that is winning the durability race..

the 8jp provides the best performance but not necessarily the best durability as the power goes up....yam engineers basic clutching should not be ignored...

I also feel that the softer stuff limits heat which we all know is the enemy and an indicator of friction from slip or too much squeeze (which often aggressive springs and weights bring if not spot on)

remember , the belt is the sacrificial anode of the system...you increase power...and increase traction...you increase load...

driving slower doesnt get cooler air in/out in volume or velocity and doesnt turn the belt over as much putting more heat into the belt...

I say as the power goes up....the most important thing to focus on is venting equal amounts of in and out (hvac like) or for off trail a electric fan!
 
I hear that.....at least the cat in 12 had a belt made for turbo power and heat.

Now all we get from YAM is a belt designed for 135hp viper NA. grrrr

I often think this is why CAT 998 has less belts blowing, just cause the have a better belt period. Checked specs, not close enough to make a cat belt fit to test either.

My ultimax snapped, but remained one long piece...the 8JP went into tiny pieces pretty much.

Is going into tiny pieces cause less damage? I have a aftermarket lower shield in place and mine went at a very low RPM so no chance for damage from the belt "swing."

What I don't want to see is really hard into it and the belt snap jumping the RPM to extremely high levels. Not good for cranks.
 
Does my post 4 video really matter though because it's on the stand with no load? Especially if there's an offset problem when shifting under load? Or are you saying that it only "looks" doglegged but it's really not? I know my stub shaft is in too far and it's going to the dealer for that soon but offset was still 60.7, which I thought was reasonable.

Oh yeah, a belt every wknd, 15 exploded now in the past 2700 miles.

Your 4th post video you brought the rpms higher and the clutches were at full shift then....and the clutches and belt looked good, it's part throttle where the clutches seem to fight one another is what I'm saying.

My clutch is rubbing on the bolt heads, I started a different post about that. Stub shaft is in too far.

Yes, I saw that post....

When you say heavier weights or flatter profile are talking about stock weights?

Stock weights weigh a lot....and they are flatter profile. Some other aftermarket weight configurations are very heavy with the springs being used. When the weights are flinging out, from what I see, it takes a lot to pull them back in. Talking about stock and aftermarket weights....especially the ones with flatter profile.
 
the 8jp provides the best performance but not necessarily the best durability as the power goes up....yam engineers basic clutching should not be ignored...

I will be the one to say that the Yamaha engineers for clutching should have been fired after the Viper mess. After riding the prototypes, I said 75% of consumers were going to be upset with the clutching....they were. The 8JP belt was designed because Yamaha couldn't put the engine more forward in the Cat chassis. Why did it take a guy like me to find the casting flash, the secondary spring coil bind on the winders and Vipers, the smaller inner diameter of the primary clutch and now more issues with the SW clutches.... Clutching engineers.... Sorry, they do know how to make a good paperweight tho :confused:
 
I would like to add,,, belt adjuster or no belt adjuster to this poll. Seeing a pattern here myself.

Add which weights and if you can, post total gram weight please....

From everything I have read, over and over....the flatter profile, heavier gram weights have been blowing more belts from what I see
 
Under constant power or in and out? Also is the traction consistent or slipping than catching?

My only break (knock on wood) was traction variation from loose to catch on top of a knob. Belt just snapped.

No question with variations in traction we need to use some caution with this much power. All that dynamic load gets chased somewhere. If I were to choose something to fail it would be the belt.
I can't use constant power, the belt will explode. My problem is that after riding for awhile the belt gets too hot and then I come up on a straight for some WOT and BOOOM!!
 
Soupy,
I can’t tell much from the video, but if your clutch Center to Center is pulling closer together under load, it will do exactly what your describing. If I had all problems your having I would cut the backside of my secondary 1/8” and see if reducing my offset helps. If it does then your motor is probably moving around.
Possibly make some sort of a tell tale to see if your motor is moving around under power.
 
Soupy,
I can’t tell much from the video, but if your clutch Center to Center is pulling closer together under load, it will do exactly what your describing. If I had all problems your having I would cut the backside of my secondary 1/8” and see if reducing my offset helps. If it does then your motor is probably moving around.
Possibly make some sort of a tell tale to see if your motor is moving around under power.
Agreed, he has my stock secondary cut down already.
Soupy, put my secondary on with no shims let it float (on stand) for a couple of cycles make sure you get after it meaning ..get it to full shift, send me a video with alot of light up in the front primary.
 
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All I know is Yamaha Tim had a Viper turbo and was blowing belts. Between him and the dealer they came up with the 8dn idea and it was the answer to not blowing belts. The 8dn seem to be a harder belt and less dust for the higher hp turbos. I am currently running one after blowing two belts under 500 miles. I switch stock helix and spring and I have 300 more miles of abuse and so far so good.
 


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