Measuring offset

[fatchance]

Ok, i guess the simple but obvious response is if it only floats before engagement what would it matter?

We are talking about float while engaged so the belt can find alignment on its own. The problem lies when guys blindly allow the secondary to float when alignment and offset is so far out to lunch it doesn't help with alignment along with the fact that allot of times the secondary won't come back in unless completely on decel. That combined with a primary that "hangs up" creates a poor situation for belt life. If you know your stuff and have good backshift with proper alignment float can absolutely work for you.

Did you search remove float? Did you understand the concept and what it would take to remove float? Clutch theory can be hard to understand at first, but usually there's one thing that you grasp and it opens the door to understanding how it all works.

 

[74Nitro]

So when the belt is up as far as it can go on the secondary and the bolt with the washer is pushing against the helix, does the secondary slide back and forth on the jackshaft or not? Mine does not and any of the winders with those washers that you are talking about for deflection adjustment wont either. I do understand the "float that you and Mike are talking about but that kind of float isnt the same as what RB200 was asking about.

He titled the thread "measuring offset". Unless you lock the clutch from floating as I described then the offset has the potential to change whenever the machine is in motion.

 

[ranger1]

Ok, i guess the simple but obvious response is if it only floats before engagement what would it matter?

We are talking about float while engaged so the belt can find alignment on its own. The problem lies when guys blindly allow the secondary to float when alignment and offset is so far out to lunch it doesn't help with alignment along with the fact that allot of times the secondary won't come back in unless completely on decel. That combined with a primary that "hangs up" creates a poor situation for belt life. If you know your stuff and have good backshift with proper alignment float can absolutely work for you.

Did you search remove float? Did you understand the concept and what it would take to remove float? Clutch theory can be hard to understand at first, but usually there's one thing that you grasp and it opens the door to understanding how it all works.

Ok, we are getting somewhere now, when you said " if it only floats before engagement what would it matter", it matters because that was the question that I was answering from RB200. I dont think anybody read his question as everybody was talking about actual clutch float and not what the question was about. Oh well, was lots of good info regardless, thanks fatchance

 

[1nc 2000]

17 winder.
57.5 mm
This is how I check my offset after I set it with the Hurricane bar.

 

[ranger1]

17 winder.
57.5 mm
This is how I check my offset after I set it with the Hurricane bar.


View attachment 177992View attachment 177993

Nice old caliper that has a gauge on the back side of it, awesome!!

 

[Yamarus]

I measured the displacement with and without a belt. 58 mm. I removed 2 mm from the rear of the secondary clutch.
Arctic cat Red White spring. XS 825 belt. In deep snow, the clutches are hot.
No tune. Stock sled.
What can be done to reduce the temperature of the clutch?

 

[ranger1]

I measured the displacement with and without a belt. 58 mm. I removed 2 mm from the rear of the secondary clutch.
Arctic cat Red White spring. XS 825 belt. In deep snow, the clutches are hot.
No tune. Stock sled.
What can be done to reduce the temperature of the clutch?
View attachment 178188
View attachment 178189
View attachment 178190

Ya I got my offset at 58.5mm and my secondary still gets hot as well. Not sure if thats just the way they are or if someone has had success in keeping them cool. Running the XS825 also

 

[fatchance]

Clutches need to be mocked up to find the proper offset. Every sled will vary.

 

[KnappAttack]

Clutches don't run "cool" when under power and in deep snow. Maybe going down the trail cruising with a lot of air going thru under the hood they do. But expecting "cool clutches", some one let me know your calibration when you get it under power in deep snow.

 

[BADSLED]

I don't remember the exact number, but I do know that my 23 needs approx 1.5 mm or so more than my 17 was running using new XS825 belts. So saying that, the Hurricane bar does not work correctly on my 23. What changed? I believe the center to center changed from my 17 to the 23. A new XS 825 belt needs to sit down further in my 23 secondary than it did on the 17 with the same deflection.

There are many factors that will make the offset perfect for every machine, center to center, belt length and width as well. Only way to know the perfect offset is to measure it with the belt under tension and use a straight edge on the belt at full shift on the clutches and measure from belt to the straight edge to find out what's perfect on your machine and belt being used.

Mike, can you provide more detail how you get the belt to stay at full shift to get the measurements? I have made an attempt to do this on my brand new '23 XTX LE by removing the primary spring, carefully clamping the primary at full shift and slipping the belt on with secondary moveable sheave only and then installing the other half of secondary sheave on splines. Helix is then installed without spring and by working the belt in the sheaves I can get the helix all the way on and tightened on the posts. At this point, I have full shift out with belt on. Now, when I put pressure on top of the belt I feel it is tad loose with maybe not enough tension sitting to low in the secondary. I would like to rotate the clutches by hand but with clamp on primary I can't make this happen. This is the best method I have come up with but I know you have done this countless times and would appreciate your input on a better method.

 

[KnappAttack]

Mike, can you provide more detail how you get the belt to stay at full shift to get the measurements? I have made an attempt to do this on my brand new '23 XTX LE by removing the primary spring, carefully clamping the primary at full shift and slipping the belt on with secondary moveable sheave only and then installing the other half of secondary sheave on splines. Helix is then installed without spring and by working the belt in the sheaves I can get the helix all the way on and tightened on the posts. At this point, I have full shift out with belt on. Now, when I put pressure on top of the belt I feel it is tad loose with maybe not enough tension sitting to low in the secondary. I would like to rotate the clutches by hand but with clamp on primary I can't make this happen. This is the best method I have come up with but I know you have done this countless times and would appreciate your input on a better method.

I can give you a few pics here and you'll get the basics of it for sure.

I use a real soft secondary spring in the secondary with no twist on it to keep belt pressure on when putting the secondary together. I took a old long clutch bolt and welded a nut on it for the pulling of the primary using threaded redi-rod. Used the old Ski Doo clutch compressor to push the primary over as a spring or clutch compressor. You can see my straight edge I use with a couple nuts that are exactly the same height under it with just a bungee to hold the straight edge on to the secondary clutch and spacer nuts. I take all shims out behind the secondary so the secondary can be moved in and out to get the perfect offset. Measure the belt to straight edge front and back till its exactly perfect. See pics for reference. You can cobble together what ever things you have laying around the shop, but the basics are laid out here for you to get idea on how to align on any machine with any clutch or belt being used. Use common sense from these photos. I'm using the dividers in the photo only for reference on belt measurements and for the photo on where to measure. Typically, I use the both the divider and the digital calipers to get the measurement exact for proper offset. Once you jig something up you can play with it to see how moving the secondary in and out changes the alignment for the offset with the belt under tension as its being run. Hope this makes sense, but the photos should lead you to the cobble needed to get the job done, doesn't need to be pretty, just needs to be accurate. Once you get it right. Measure the shaft to outside of secondary to get the spacing you need. On my 23 right now, I sit the secondary right against the snap ring and bolt it tight for perfect clutch alignment with the TAPP. I can't machine anything off the secondary or remove the snap ring or the secondary will hit the aluminum frame hard on full shift. It just ever so slightly rubs it as it is now with the snap ring in place. The center to center is longer on my 23 vs my old 17 so the movable in the secondary moves further as it goes into a higher OD than the 17 did. This is why I have ended up with 1.5 mm more offset on my 23 than the 17 was with the same setup on it.

 

[fatchance]

Mike I've been asked this a bunch and I'm sure you get asked this waaay more than me. This is the optimal offset for full shift where we all know, this is when the heat builds. I tell guys, I know these are 200 plus HP sleds, but I think there's an advantage for guys that don't live or even get to full shift or the cruisers that might do a blip close to full shift. Before you mock up if given the opportunity mark the clutch with a marker and see where it wears at the highest speed you spend the most time. Mock up the clutch at this point so you have the perfect alignment at that speed. Just didn't expect to align the clutch for say 80 and do a three mile run across the lake wide open!

 

[KnappAttack]

Mike I've been asked this a bunch and I'm sure you get asked this waaay more than me. This is the optimal offset for full shift where we all know, this is when the heat builds. I tell guys, I know these are 200 plus HP sleds, but I think there's an advantage for guys that don't live or even get to full shift or the cruisers that might do a blip close to full shift. Before you mock up if given the opportunity mark the clutch with a marker and see where it wears at the highest speed you spend the most time. Mock up the clutch at this point so you have the perfect alignment at that speed. Just didn't expect to align the clutch for say 80 and do a three mile run across the lake wide open!

Kinda why people let the secondary float. The problem with floating however is that when under power if the secondary is floated outward say in a roll on race and you grab a handful, it will stay stuck outward and not self align at the top end until letting off the throttle. Life is not perfect for the belt no matter what you do with it, but belts typically start to fail by breaking cords and blow when under full power at high belt speeds, so thats where I set them for myself. Self aligning and floating has never worked for me, but locking them down after setting the alignment has worked, so I let them be out of alignment at low speed, as more often then not, its spends little if any time there and not under full power anyway so the mis-alignment is is a non issue, even cruising at low-mid throttle RPM the belt is up in the higher shift ranges, so really a moot point honestly. People can do as they wish, I'm just stating what has worked for me on high powered machines like the Winder, turbo RX-1s, Apex's and turbo 1200's.

 

[fatchance]

Agree with the secondary grabbing. I never had much luck with float, but I also would go for heavy backshift. I would attribute the misalignment to that Stock primary sticking at times as well! It's probly just me trying to help micromanage belt wear, but like you I will continue to mock it up at full shift (thankyou). It's just too easy to squeeze that throttle and not let go until you run out of real estate and it doesn't take long!

 

[sideshowBob]

I am in the minority of riders as I have always been fully floating the secondaries on all my sleds that have had a jackshaft, super charged, turbo, mods sleds and trail sleds, Yamahas and other brands since the mid 1970s.
I have never had an issue where a secondary has stuck out of alignment causing belt failure but admittedly at times, especially in aggressive on and off the throttle trail riding, the secondary probably would have been misaligned for a short time as it would surely stick in position on the jack shaft.
I float the secondaries more for ease of engine, chassis, and clutch alignment to lesson setup time and energy. LOL...Lazy Man approachWith my wife and son's sleds, my race sleds, and my trail sleds at one time I was maintaining up to 8 sleds per season...thank goodness I am down to only 4 sleds now!
There is no doubt shimming and fixing the secondary in a specific alignment with the primary is a more precise way of doing it but for me I haven't seen the requirement in my applications.
Interesting enough, in the group I ride with, I am the only one that fully floats my secondaries and I am the only one that hasn't experience belt issues regardless of the brand of sled. TOUCH WOOD!

Works for me.