TAPP / PRO4

[ISLANDRACING]

As the title states, I wanted to start a specific post for STRICTLY for this combination. The more info provided on this post: setup, belt, riding style ( corner to corner, wide open long trails etcetc. ), what adjustments did what, what worked and what didn't work, blown belts, What HP level, etcetc. you get the point. Also, when "recommendations" are made, don't just make a recomendation, please state WHY you feel that will work, or what that setup will do over whats already done. There has been some good info shared on other posts. What I do find hard to believe is that this combo cannot at minimum be setup EQUAL performance to a stock setup, but have the "duribility" of being billet vs cast.
2019 SRX Hurricane 270SM. Initially my TAPP was set up with Black Spring, +1 rollers, clickers on 3, Ramps on A, shortest roller bolt empty, arms empty, Offset 59.1mm. PRO4 43/34 Helix, Black/Purple spring, wrap in center STD setting.
Ran the XS825 belt for the first 60 miles. RPM at this combo was right at 8900. Dave at PL repeatedly stated to run the 8DN belt, and knowing that that this belt is a BRUTE, I made the switch. The rpm went to about 9150, so I added the middle 1-1/2 ( middle size ) roller bolts, to bring the R's down.
With this combo the TAPP ran cool and the PRO4 was very warm ( but could hold hand on it ) after a few mile blast of EXTERMELY AGGRESSIVE full on full brake corner-to-corner through the tight and twisties. I did snap the belt at aprox 325 miles.
This weekend I am going to try the AC green and see how it works.

 

[WinterWolf]

So you snapped the 8 dn? I wonder if you would have snapped the XS as quick...? But full on brake and then full on acceleration immediately following each other is tough on belts with these monster Tunes.

I’m running what you are running, but twisted the spring one more hole to the right, and clickers to #4, performance was even better/excellent. And found the same temps as you did but with XS belt. With one more trip coming up Thursday...gonna probably leave it be...and just enjoy the riding for now, but maybe a tad more helix angle at the back side(43/36-43/38) might do it.

I’ve been in contact with Mark from Pro 4, (fabulous guy, and very quick to respond) and he said he’s a tad baffled by the secondary being warmer too? Told me to increase the wrap one notch(which I did as I said above), but also said that maybe a bit more helix angle on the back side might do the trick as I mentioned in the previous paragraph.

Personally, I don’t feel the warmth of the Pro 4 secondary as I’m experiencing it, is that severe where it will sacrifice belt durability, but something as simple as a spring change or a helix change, or a combo of both would probably do the trick.

And I completely and utterly agree with you on the quality and the durability of these pieces. These are far superior in every way to the stock clutches in every aspect that can be measured... hands down. I’m not going back to any of the stock stuff after having these. So it’s just a matter of finding the combo that works for each riders specific set up.

 

[STAIN]

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.

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.

 

[mainedrummer]

Great idea for a thread!
I’d also like to know the gearing and type/quantity of traction enhancements someone is running.
These will both be relevant.

 

[snowbeast]

As the title states, I wanted to start a specific post for STRICTLY for this combination. The more info provided on this post: setup, belt, riding style ( corner to corner, wide open long trails etcetc. ), what adjustments did what, what worked and what didn't work, blown belts, What HP level, etcetc. you get the point. Also, when "recommendations" are made, don't just make a recomendation, please state WHY you feel that will work, or what that setup will do over whats already done. There has been some good info shared on other posts. What I do find hard to believe is that this combo cannot at minimum be setup EQUAL performance to a stock setup, but have the "duribility" of being billet vs cast.
2019 SRX Hurricane 270SM. Initially my TAPP was set up with Black Spring, +1 rollers, clickers on 3, Ramps on A, shortest roller bolt empty, arms empty, Offset 59.1mm. PRO4 43/34 Helix, Black/Purple spring, wrap in center STD setting.
Ran the XS825 belt for the first 60 miles. RPM at this combo was right at 8900. Dave at PL repeatedly stated to run the 8DN belt, and knowing that that this belt is a BRUTE, I made the switch. The rpm went to about 9150, so I added the middle 1-1/2 ( middle size ) roller bolts, to bring the R's down.
With this combo the TAPP ran cool and the PRO4 was very warm ( but could hold hand on it ) after a few mile blast of EXTERMELY AGGRESSIVE full on full brake corner-to-corner through the tight and twisties. I did snap the belt at aprox 325 miles.
This weekend I am going to try the AC green and see how it works.
View attachment 153599

Why did you abandone the xs825 and than install 8dn? Did the xs825 not feel good or was it something else?

 

[ISLANDRACING]

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.

 

[WinterWolf]

Hey Island, yes I ride northern Maine..big trails lots of high speed running. Mark from Pro 4 just suggested Trying the 46/36 so as to eliminate some heat in the secondary perhaps?

If I ordered it today from Dalton, I don’t know if I could get by Thursday when I’m leaving on my trip??? And would it even make that much of a difference in cooling the secondary. My secondary is not scalding hot..so I’m a LIL tentative on pulling the trigger on another helix just yet?

Ahh decisions decisions lol...??

 

[ISLANDRACING]

Very familiar. Actually heading up that way on Thursday also. Try Tom, he may have the helix in stock. If I always rode Maine, I probably would of had that helix from the get-go myself.

 

[WinterWolf]

Very familiar. Actually heading up that way on Thursday also. Try Tom, he may have the helix in stock. If I always rode Maine, I probably would of had that helix from the get-go myself.

Ahh good idea..maybe I’ll call Tom this morning?

 

[J & J Racing]

steeper angle you can get away with the faster the up shift
Shallower slows it
Shallower equals more clamping force
Steeper opposite
shallower backshift more
If you snap a belt in half you have a problem. I am guessing your heat in secondary is caused by slip which is caused by TOO much clamping force or start softening spring
I personally ran a 46 36
46 38. 46 40. 44 40. 44 38

from my experience
Unless you are riding in the loose snow all the time I wouldn’t run less than a 36

traction is biggest key

if you always are spinning you probably need shallow finish
A steep angle with a spinning track equals sucking belt in secondary
It shifts too fast

 

[WinterWolf]

Very familiar. Actually heading up that way on Thursday also. Try Tom, he may have the helix in stock. If I always rode Maine, I probably would of had that helix from the get-go myself.

Tom recommends going down one spring/less spring...not less helix in his opinion. Maybe something to think about next year lol??

 

[STAIN]

STAIN is running the STM 43/32 custom helix

I have removed that helix presently. I feel it was overclamping my secondary.......

 

[ISLANDRACING]

If you snap a belt in half you have a problem.

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.

 

[J & J Racing]

Don’t take this the wrong way but if you ride a sidewinder like that nothing will last.
buy a 600 or 800 2 stroke
The 8dn is going to eventually cut grooves in the sheaves with what you describe
The chain case will fail very fast

5-600 miles on brakes! Wow

I don’t think any component on the sled is designed nor built to ride as you described above

jmo and I hope I’m wrong

 

[WinterWolf]

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.

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.