TAPP / PRO4

[Crossfire12]

Talked with Tom yesterday, and he has either set them up like mine(43/34 with black purple spring), or 46/36 with white spring...which he said is a lil more of a lake set up, but some guys like it.
Keeping mine the way it is for this next trip on Thursday...He didn’t have any 46/36 or white springs in stock, so I’ll try that perhaps next season?

I do like the super quick snap and responsive nature of my set up though as it currently is. I’ve only got about 150 miles on this set up currently..so I hope to put 400-500 more on over the long weekend when I head up Thursday night.

Which hole are you using with those springs 1st?

 

[Crossfire12]

Talked with Tom yesterday, and he has either set them up like mine(43/34 with black purple spring), or 46/36 with white spring...which he said is a lil more of a lake set up, but some guys like it.
Keeping mine the way it is for this next trip on Thursday...He didn’t have any 46/36 or white springs in stock, so I’ll try that perhaps next season?

I do like the super quick snap and responsive nature of my set up though as it currently is. I’ve only got about 150 miles on this set up currently..so I hope to put 400-500 more on over the long weekend when I head up Thursday night.

Which hole are you using with those springs 1st?

 

[WinterWolf]

Which hole are you using with those springs 1st?

2nd from the right.

 

[Crossfire12]

2nd from the right.

That’s pro4 or STM?

 

[ISLANDRACING]

The PRO4 has 15 settings. going from CLOCKWISE: +1/2 1-5 , STD 1-5, and -1/2 1-5. Specifying which hole the tang is in would eliminate any confusion. EXAMPLE: STD 3 , STD 5, -1/2 4 etcetc. Winter: does your "2nd from the right" mean -1/2 4 ?

 

[Crossfire12]

The PRO4 has 15 settings. going from CLOCKWISE: +1/2 1-5 , STD 1-5, and -1/2 1-5. Specifying which hole the tang is in would eliminate any confusion. EXAMPLE: STD 3 , STD 5, -1/2 4 etcetc. Winter: does your "2nd from the right" mean -1/2 4 ?

I have STM it has 5 holes, what hole would you start with , first hole left soft, dalton white/ 46/36 helix. Pro 4 seems complicated, something to get used too,

 

[ClutchMaster]

I run Hurricane stock muffler tune to 270 %95 of the time.
I bought this set up because I did not trust the stock primary to hold up on long saddle bag trips. I paired it with Pro-4 secondary because I was there and it was suggested to be better. I cannot remember how the primary was set as bought, I knew in the beginning it was FAR too heavy!!!! I have pulled over 20 grams of weight from each arm in an attempt to get it right. I have been struggling to find proper clutch balance since my purchase, often times thinking I was close then having something rear its head, telling me I was wrong.

I trail ride, no lake racing. Trails from tight and twisty to logging roads and rail beds. I want corner to corner performance, not all out speed/top end.
Last week it was set up as
Primary spring-----blue(lightest)100-190
Rollers +1, shortest bolts, 1 bolt(2.5g)in arm, no washers---22.5 grams per arm
Clickers #3
Secondary Cat green/Dalton white wrapped to 1 hole tighter than center
Helix 43-32
Belt xs825--I went to this belt early in my tuning process after snapping 2 8JP, I have yet to ruin a XS825 in 3k miles.
Engagement @3000 rpm
I found the sled to pull hard off the bottom and strong mid. the RPM would go from 9100 in the morning(cold) to sometimes 8400 on the warmer days in the afternoon. Secondary clutch would get hotter as the ambient temps climbed. Primary temp would fluctuate. I found it hard to adjust because I kept struggling to find RPM's and was out of adjustment on the primary as far as going lighter, save buying even more rollers. On warm days my secondary started to look like this.
View attachment 153631 NOT GOOD!!!!
At this point, in my mind, without going to smaller rollers, I cannot loosen my secondary without loosing RPM. I was also going to go to a stiffer primary spring in an attempt to gain RPM. After some conversation with Knapp, I learned I was actually over pinching the belt. This caused it to transfer rubber to the sheaves, especially when the ambient temps climbed. This was something I had never experienced, though suspected. This was why in the morning my RPM's were decent (cold) and when the afternoon rolled around it went south. It also meant the secondary set up was very inefficient. My motor was working to open the clutch, not move it forward.
Friday's ride. New set up.
Primary spring Black (middle) 140-210 ( more RPM)
Rollers +1, shortest bolts, 0 bolt in arm, no washers-- 20.5 grams per arm
Clickers #3
Secondary STOCK unit . Dalton B/O wrapped to 90 degrees
Helix stock 35 degree
Belt Exact same XS825
Engagement @3300
Test ride of 160 trail miles. RPM is almost SPOT ON. Any small adjustment can be made with clickers. Small overflash on bottom then it settles in at @8700 and climbs. Pulls hard . Great throttle response and pull at higher speeds. TAPP primary AND stock secondary are cool to the touch after a long run. I will keep this set up for my upcoming saddlebag trip.
I will try to tune the Pro-4 secondary when time allows to get it to run like the stocker. I now have an idea of what it needs to be more efficient. I have it, I might as well use it. To be honest, I think the only advantage of the Pro-4 over the stock secondary clutch at this point is the price of the tuning components. Yeah it is pretty, but does really work better? Meh.
I have been fooling with snowmobile clutchs for over 20 years but not on this horsepower level. I learned a few things during this process for sure.

Awsome ACTUAL test info! If your following this thread and didn’t “Like” this post you have issues.

It was the 8DN that snapped. The 8DN's have always been strong, tough belts and have always taken a LOT of abuse over the years. I feel the 8DN is a stronger belt than the XS825 speaking solely from a "break" point and feel the belt would have snapped sooner running the XS. Which ones cords are stronger and will actually snap first on a "pull" test who knows. Many do not like the 8DN due to the fact that it is so hard. Also, Dave at Powder Lites ( TAPP Clutch ) stated many times to me to run the 8DN. I did experience much more brake dust in the short time running the XS825 over the 8DN. I didn't have any signs on the secondary from either belt of slipping or over pinching. Due to being longer, the 8DN does sit higher in the secondary than the XS825 when deflection set properly for both belts.
Getting to the Helix, Seems the most popular choices range between the 43/34 ( being the most popular ), 44/36, and 46/36. I was "told" that for my primarily type of riding: generally corner to corner, occasional open fields, want that back-shift, to go with the 43/34 and if I did that looooong wide open trails like upper Maine that the 46/36 would be the choice. Reading through all the different posts and people stating what worked for them, i see recommendations to go lower on the finish as STAIN is running the STM 43/32 custom helix, and others are recommending to go the opposite way and go much higher. Not saying anyone is wrong or right, But as I stated in the first post of the thread, EXPLAIN the reason for the recommendation. What will your recommendation do, or feel it would do, or what effects it will have for someone over the current setup. etcetc. you get the point. WINTER, When talking with Mark, did she say why to go up on the helix? I believe you ride Maine, Millinocket area if i believe. That is those long wide open trails Im talking about, which I was told to use the steeper helix in those conditions.

The 8DN is a strong belt no doubt but it’s so hard it can damage sheaves, also it’s very stiff and hard to bend making it inefficient and robs horsepower.

 

[WinterWolf]

That’s pro4 or STM?

Pro 4.

 

[WinterWolf]

The PRO4 has 15 settings. going from CLOCKWISE: +1/2 1-5 , STD 1-5, and -1/2 1-5. Specifying which hole the tang is in would eliminate any confusion. EXAMPLE: STD 3 , STD 5, -1/2 4 etcetc. Winter: does your "2nd from the right" mean -1/2 4 ?

It is confusing but mine is on Standard 4.

 

[ClutchMaster]

EXCELLENT info you contributed!
I do believe that the "belt snapping" is a combination clutching related and the extreme aggressive corner to corner "next level" riding. When I go through a set of brake pads in 500-600 miles, people say there's a problem there also

There is definately some combos to try. I do like the backshift of the 34 but would be willing to give some up if it is going to be more forgiving of the grab on the belt, lighter spring and/or 36 on the helix. The TAPP is always going to be a grab monster and dont think there is too much you can do to change that. I feel that grab on the front+grab on the back +traction + the power of these tuned Winders = snap. I feel the 8DN will last a lot longer and still even get 1000+ miles out of it even of it slipped a little vs the extreme grab causing it to snap.

Both the 8dn and XS belts are good for over 400 horsepower so at trail power levels either one will work fine and last if clutched properly.
Using the 8DN will wear your sheaves on that beautiful new clutch and rob horsepower. Do yourself a favor and switch too the XS belt instead of trying to use a belt that was designed to last for 3~5k miles on a lower horsepower machines.
I run an STM secondary, similar to the pro4 and stain has freely given you a good baseline setup for the XS belt and your clutch combo. You could absolutely use the lower angle helix with your setup and XS belt, it would just require a much softer secondary spring imo.
I think it’s red and white but my Alzheimer’s is getting the best of me.

 

[ISLANDRACING]

Both the 8dn and XS belts are good for over 400 horsepower so at trail power levels either one will work fine and last if clutched properly.
Using the 8DN will wear your sheaves on that beautiful new clutch and rob horsepower. Do yourself a favor and switch too the XS belt instead of trying to use a belt that was designed to last for 3~5k miles on a lower horsepower machines.
I run an STM secondary, similar to the pro4 and stain has freely given you a good baseline setup for the XS belt and your clutch combo. You could absolutely use the lower angle helix with your setup and XS belt, it would just require a much softer secondary spring imo.
I think it’s red and white but my Alzheimer’s is getting the best of me.

Clutch your input is greatly appreciated and thank you!
I haven't ruled out the XS.
Hear out my .02 for a second. My choice is from a "strength" standpoint. Longevity ( from wearing out ) is not a concern nor is price of the belts, as I change then regularly regardless but snapping a belt is.
If the choice is between grooving the clutch, and giving up some HP versus coming into corner hot, whacking the throttle, needing that rear-steer, snapping the belt, and ending up in the woods , dead.. kind of have to lean toward preventing the second.
Honestly I do not know which belt is more resistant to snapping for all I know it may be the XS. then the choice would be a no-brainer.

Check out minute 7: 30 in this video. Wish i could see a side by side of the two.
May have to pick up some lighter springs and play EPI purple, and i saw that red/white you mentioned. too late for this weekend though. may try the XS with the AC green

 

[ClutchMaster]

Red/White cat Spring

 

[ISLANDRACING]

Red/White cat Spring

Yes AC part# 0648-114

 

[STAIN]

They are using a monster secondary spring in that video, looks like the Bikeman orange---120-180!!! Just the spring i was trying to avoid.

if you are going to use that red/whites Cat spring you will need to pull a TON of weight out of that TAPP primary

 

[ClutchMaster]

They are using a monster secondary spring in that video, looks like the Bikeman orange---120-180!!! Just the spring i was trying to avoid.

if you are going to use that red/whites Cat spring you will need to pull a TON of weight out of that TAPP primary

Absolutely! Remember he’s running the 43/34 helix. I tested the AC red/white yesterday with my 46/36 and I just couldn’t get enough weight out of my arms on the tips. RPM drops off up top. Clutches ran super cool even with twist at 4th hole position on my STM. If I had a 43/34 I would have tried it. You will probably need a primary spring with more finish rate also.

XS belt I should say also

I pulled 5 grams out of the heal otherwise it was a boggy. I’m not sure you’ll be able to pull enough weight with the +1 rollers?