Blown Belt

[newtron]

The other question I was wondering what guys think is this.. Does the higher helix angle back shift better and keep the belt deflection/tension more consistent through out the whole RPM range and stop some of the hurkey/jerky(IMO) stuff that contributes to blowing belts???? (or have I lost my marbles).. I know Coil bind is also a major issue (my secondary was machined for it).. Just seems to me since I have gone to a slightly higher helix angle(and 6/1) the clutching feels and act more fluid and responsive. (NOT LAZY, which was how it felt with stock helix).. I know this isn't a great example BUT I ran my sled a little on a stand and WATCHED the belt work through the secondary with different helix and stock spring wound to 6/1 and it just seems more responsive(opening and closing better and faster and more consistent with the primary.. Which keeps the belt tension more consistent?? Just blabbing out loud and trying to see if my observations are what other guys see or think.

No. More shallow angle backshifts better.

Great clutch info in the tech pages

 

[cannondale27]

Okay someone knows kind of what I feel and think about the clutching before my helix change.. I have not lost my marbles! Thanks Canondale for saying belt whip that's what I was trying to describe. And IMO the laziness of the stock helix and spring and or even roller issues, and spring bind combine to = belt whip = BANG goes belts

I remember watching a Cat whipping the belt back then side by side with a Viper. Wow what a difference! Not saying that is behind all belts blowing but its complicated. Depends on how you ride and mods you have also. If its anything like the Cats there is no one solution. Lots of power=Blown belts for some. Has always been that way. I will say the UTV guys have it worse. One thing that I have taken note of from them is those that use a belt which is always under tension(no deflection) and a oneway bearing in secondary have way better belt life but the limits of a fibre/rubber belt are definitely showing their ugly face.

 

[cannondale27]

No. More shallow angle backshifts better.

Great clutch info in the tech pages

There is for sure. Wonder what Turk would have to say about this? I will say this. If you are thinking about your belt I bet you are riding differently than before. Wish that wasn't the case.

 

[ROCKERDAN]

who has blown a 8dn? (not gates)

Gates will not withstand the big power, we found that out on 12 cats, even though I love the gates on my doos they dont have the strength IMO.

I just wonder if the 8dn being tad longer will not blow? Arent they a tougher belt too?

 

[newtron]

There is for sure. Wonder what Turk would have to say about this? I will say this. If you are thinking about your belt I bet you are riding differently than before. Wish that wasn't the case.

I'm done with the 8jp on my sidewinder. Gave 2 of them a 1400 mile chance but that's it. Switched to 8dn todayand I have Cool and clean clutches.

Made some clutching changes along with the 8dn and if my clutches are still good after my 200 mile ride Friday I'm sticking with the 8dn

 

[shagman]

The other question I was wondering what guys think is this.. Does the higher helix angle back shift better and keep the belt deflection/tension more consistent through out the whole RPM range and stop some of the hurkey/jerky(IMO) stuff that contributes to blowing belts???? (or have I lost my marbles).. I know Coil bind is also a major issue (my secondary was machined for it).. Just seems to me since I have gone to a slightly higher helix angle(and 6/1) the clutching feels and act more fluid and responsive. (NOT LAZY, which was how it felt with stock helix).. I know this isn't a great example BUT I ran my sled a little on a stand and WATCHED the belt work through the secondary with different helix and stock spring wound to 6/1 and it just seems more responsive(opening and closing better and faster and more consistent with the primary.. Which keeps the belt tension more consistent?? Just blabbing out loud and trying to see if my observations are what other guys see or think.

I hope this helps. Brief explanation of shift I wrote for another member as it pertains to reverse helix.

6-1 wrap will slow down the upshift and speed up the backshift. Slowing down the up shift allows the engine to build rpms quicker which makes the turbo spool up quicker. This is done to get to max torque faster and make sled quicker. Then with the reverse helix you hit your second steeper angle which holds your rpms. On the other side being back shift, the steeper angle needs a little help with this.
Steeper angle is slower backshift while flatter angle is quicker back shift. On the spring more wrap is quicker backshift and less wrap is slower backshift. And more wrap is slower upshift and less wrap is faster upshift.

Hope this isn't too confusing.



Sent from my iPhone using Tapatalk

 

[jonlafon1]

No. More shallow angle backshifts better.

Great clutch info in the tech pages

That's why I ask what you guys think? I only was trying to describe what I thought the difference was with MORE helix angle. And the belt hanging or whipping. Not saying that's what is happening on all the sleds.

 

[shagman]

who has blown a 8dn? (not gates)

Gates will not withstand the big power, we found that out on 12 cats, even though I love the gates on my doos they dont have the strength IMO.

I just wonder if the 8dn being tad longer will not blow? Arent they a tougher belt too?

Dan, I ran the gates Carbon C12 in both lengths on asphalt and snow with my turbo viper with great success. Blew one belt in 3200 miles and they warrantied that one due to a bad batch. I'm currently testing a 8dn length one on the winder and so far so good. 300 miles. But I know of a lot of blown ones which doesn't make sense. Seems like 2 sleds cant get the same results with them.

 

[PowderFalcon]

I have heard the 8DN wont make as much power as the 8JP because it is slight longer and wont shift out in the secondary as well. Anyone seeing this?

 

[newtron]

I have heard the 8DN wont make as much power as the 8JP because it is slight longer and wont shift out in the secondary as well. Anyone seeing this?

U will lose 2-3 mph on full shift out. So 119 instead of 122 geared out. No loss in power just top end

I have been through this with my last 2 viper turbos. I just geared up and was good to go.

 

[bleedyamaha]

Everyone I have checked and made the clutch offset around 61mm has been good since.

ok am I doing this right? I also have a shim behind the secondary shaft. What you think?

 

[shagman]

View attachment 126191 View attachment 126190 View attachment 126189 ok am I doing this right? I also have a shim behind the secondary shaft. What you think?

As long as your holding the tape straight it looks good. your real close to 61mm in the pic.

 

[shagman]

U will lose 2-3 mph on full shift out. So 119 instead of 122 geared out. No loss in power just top end

I have been through this with my last 2 viper turbos. I just geared up and was good to go.

My primary was machined on my viper and I picked up 4 mph with the 8dn.

 

[bleedyamaha]

As long as your holding the tape straight it looks good. your real close to 61mm in the pic.

Thanks. Thats why i did it a couple times. Kinda tricky holding everything in place and taking a picture. I havent ran it with the shim behind secondary yet. Might tighten up the osp adjuster a bit to bring the 8dn up a bit.

 

[shagman]

Thanks. Thats why i did it a couple times. Kinda tricky holding everything in place and taking a picture. I havent ran it with the shim behind secondary yet. Might tighten up the osp adjuster a bit to bring the 8dn up a bit.

Shim fixed mine.