Ulmer Dyno

[STAIN]

Just the peak was the difference otherwise all was virtually the same.

The reason I ask is because when I ran the TAPP on a couple of different sleds with different tunes, I felt like the sleds where stronger at low speed acceleration. They felt like they they pulled "harder"
I attributed this, rightly or wrongly, to the TAPP "upshifting more aggressively" than stock clutches.
After reading, and talking, to Knapp and Allen and reading their posts, it seems like maybe that my set ups where not optimal with the stock clutch.
I wish I had more time to run and test---and learn. What I wouldn't give to just hang out in one of these shops for a weekend and soak up some knowledge!!
Just when I think I am getting a grasp on what is happening with these clutches I find out how much I dont know!!
I really like these types of conversations and this site is one of the only places to have them with people who I would consider experts.

 

[Srxspec]

The reason I ask is because when I ran the TAPP on a couple of different sleds with different tunes, I felt like the sleds where stronger at low speed acceleration. They felt like they they pulled "harder"
I attributed this, rightly or wrongly, to the TAPP "upshifting more aggressively" than stock clutches.
After reading, and talking, to Knapp and Allen and reading their posts, it seems like maybe that my set ups where not optimal with the stock clutch.
I wish I had more time to run and test---and learn. What I wouldn't give to just hang out in one of these shops for a weekend and soak up some knowledge!!
Just when I think I am getting a grasp on what is happening with these clutches I find out how much I dont know!!
I really like these types of conversations and this site is one of the only places to have them with people who I would consider experts.

My clutch recipe has changed in the last few years. I have gone to an aggressive profile matched with my soft primary spring, steep helix, and stiff secondary spring. The results = grabbing the belt at 320 hp with only 67-68 total grams.

 

[DooZ]

Thanks again Allen. Being a Cat guy, I'm curious where your Yami set-up compares to a Cat clutch set-up? I'm sure you've played with a few (I know of at least one lol)

 

[STAIN]

steep helix, and stiff secondary spring.

Do you feel this way is more "efficient" then a shallow helix and soft spring? Or this just another way to get to the same place? Is the belt temp lower this way?
when you steep do you mean steep compared to stock (35deg) or STEEP (50 deg plus)
This seems more like the way the 2 strokes where clutched. Why the sidewinder went to 35 deg vs the 45 degree range is above my knowledge.
I do know, talking with Gilles Gagne , He claimed the correct angle for the Yamaha secondary is almost always 45 OR within a few degrees of 45

grabbing the belt at 320 hp with only 67-68 total grams.

This must increase throttle response on trail vs. heavy weights--correct? I also assume it must also be easier on wear parts in the long run.

 

[Srxspec]

Thanks again Allen. Being a Cat guy, I'm curious where your Yami set-up compares to a Cat clutch set-up? I'm sure you've played with a few (I know of at least one lol)

My Yamaha weights will bolt directly into the ADAPT clutch and I have used them, but only on a stocker. The next sled I'm doing I will be using my clutching in the ADAPT primary with Cat secondary to start out with (MC Xpress large turbo setup, 350 hp on pump gas). Then comparing TAPP with Cat secondary, TAPP with TAPPS and also will compare a STM secondary as well.

Do you feel this way is more "efficient" then a shallow helix and soft spring? Or this just another way to get to the same place? Is the belt temp lower this way?
when you steep do you mean steep compared to stock (35deg) or STEEP (50 deg plus)
This seems more like the way the 2 strokes where clutched. Why the sidewinder went to 35 deg vs the 45 degree range is above my knowledge.
I do know, talking with Gilles Gagne , He claimed the correct angle for the Yamaha secondary is almost always 45 OR within a few degrees of 45

This must increase throttle response on trail vs. heavy weights--correct? I also assume it must also be easier on wear parts in the long run.

There's a million ways to skin a cat. We could (and I have) spend a day on the dyno and take 5 or 6 setups and get the same results, each will have a little unique feature to itself in some way, but none of them would be "wrong" so to speak.

Shallow helix and soft secondary spring are fine up to about 270 hp IMO. My steep is steep compared to stock (46ish start 42ish finish when comparing to stock, I say this because the STM helixes are cut differently than OEM and the numbers don't match up).

Yes & yes.

 

[Turboflash]

I switched from Team to ADAPT setup (at 320+ HP). Primary weight went from close to 80 grams (Team) down to 70-72 (ADAPT) with softer primary spring and higher (progressive) angle secondary helix. Both clutches run very clean, no sign of slip. Cooler belt temps.
Works for me.

 

[Srxspec]

Also, I just screen recorded a few of my Facebook posts, will try to post to youtube as I get some free time.

 

[Fleecer]

Do you feel this way is more "efficient" then a shallow helix and soft spring? Or this just another way to get to the same place? Is the belt temp lower this way?
when you steep do you mean steep compared to stock (35deg) or STEEP (50 deg plus)
This seems more like the way the 2 strokes where clutched. Why the sidewinder went to 35 deg vs the 45 degree range is above my knowledge.
I do know, talking with Gilles Gagne , He claimed the correct angle for the Yamaha secondary is almost always 45 OR within a few degrees of 45

This must increase throttle response on trail vs. heavy weights--correct? I also assume it must also be easier on wear parts in the long run.

The old 2 strokes and vipers used a button secondary, which needed more helix to open. Mounting a stock viper secondary on a sidewinder with a straight 45 will turn exact rpm as stock factory secondary with a stock 35 helix. The roller secondary requires 10 degrees less of helix for the same shift.

 

[Fleecer]

Last year, I converted my Thundercat to Yamaha clutches. Many have asked, "Why would you do such a foolish thing?".

My answer, "Because I want to go fast.....and I need my left foot to earn a living!!"

Thanks for the videos. Very educational and transparent.

 

[DooZ]

My Yamaha weights will bolt directly into the ADAPT clutch and I have used them, but only on a stocker. The next sled I'm doing I will be using my clutching in the ADAPT primary with Cat secondary to start out with (MC Xpress large turbo setup, 350 hp on pump gas). Then comparing TAPP with Cat secondary, TAPP with TAPPS and also will compare a STM secondary as well.



There's a million ways to skin a cat. We could (and I have) spend a day on the dyno and take 5 or 6 setups and get the same results, each will have a little unique feature to itself in some way, but none of them would be "wrong" so to speak.

Shallow helix and soft secondary spring are fine up to about 270 hp IMO. My steep is steep compared to stock (46ish start 42ish finish when comparing to stock, I say this because the STM helixes are cut differently than OEM and the numbers don't match up).

Yes & yes.

So I'm still using the deadly Team Primary, with a STM Secondary. When you say STM helixes are cut differently than OEM, how does my straight 45 STM compare to your Yami stuff?

 

[STAIN]

I know the TEAM primary has a bad rep but I believe if your clutching is right AND you properly set the moveable sheeve to belt clearance they can last, I have seen it on tuned Cat's...

 

[Srxspec]

So I'm still using the deadly Team Primary, with a STM Secondary. When you say STM helixes are cut differently than OEM, how does my straight 45 STM compare to your Yami stuff?

Sorry, I should have stated STM Yamaha helix angles vs OEM Yamaha helix angle. If you use a STM 39/35 helix on a Sidewinder secondary, it will shift more like a 45/41. The angles don't match an OEM Yamaha Sidewinder helix. Not sure how that even happened, since I sent them the first Sidewinder prototype helix I was able to get my hands on, but regardless they don't match.

 

[STAIN]

Sorry, I should have stated STM Yamaha helix angles vs OEM Yamaha helix angle. If you use a STM 39/35 helix on a Sidewinder secondary, it will shift more like a 45/41. The angles don't match an OEM Yamaha Sidewinder helix. Not sure how that even happened, since I sent them the first Sidewinder prototype helix I was able to get my hands on, but regardless they don't match.

Is there a reason you use STM helix's that don't match stock angles vs a Dalton that does seem to match? Price? Availability? Quality?
Dalton seems to be @ $30 higher

 

[fatchance]

My clutch recipe has changed in the last few years. I have gone to an aggressive profile matched with my soft primary spring, steep helix, and stiff secondary spring. The results = grabbing the belt at 320 hp with only 67-68 total grams.

It's funny you should mention this Allen because I have been a big proponent to the steep helix and stiff secondary spring with stock and the TAPP set up, however I have stuck with a more heavy weighted primary with a more stout spring because it tended to ET quicker and obviously load the motor more. I will definitely revisit this angle of testing if given the opportunity this season.

 

[stone88]

Sorry, I should have stated STM Yamaha helix angles vs OEM Yamaha helix angle. If you use a STM 39/35 helix on a Sidewinder secondary, it will shift more like a 45/41. The angles don't match an OEM Yamaha Sidewinder helix. Not sure how that even happened, since I sent them the first Sidewinder prototype helix I was able to get my hands on, but regardless they don't match.

How does the Dalton helix compare to STM or stock I always run Dalton just because I have so many of them I try to stick to one brand because of the differences.