Ultimax is inconsistent on team clutches

[yamamarc]

Anyone one else try the ultimax on the team clutches and have poor results?
Last year I purchased the ultimax xs827 and had a 800 rpm drop and horrible performance. I contacted Timken and they sent me a new xs829 saying I had the wrong belt. (Awsome customer service)
I got out Thursday and had chance to get some good wot runs on a lake with the new belt and no luck . My rpm's were so inconsistent one run they dropped to 8300-8400 and the next run I was hitting the rev limiter and over reving. My first thought was something was binding in clutches. After talking with a buddy I decided to go back to the stock cat belt. We went back out riding Friday and Rpm's were perfect and consistent holding the same # each pass.
I decided I am just going to stick with the stock belt and not bother trying any other brands!

 

[stevewithOCD]

I tested an XS last year against other belts.
According to some, I did NOT pull any weight out of primary so it was probably not a fair test.
I will test this weekend with stock belt, temp gun, RPM & speedo watch.
Then i'll pull all my weight out & repeat next day with the XS.

I am told this belt needs a 100 miles or so to "break in" to re-gain my last 100 or so rpm's.
I really don't like telling my Tuned 900T bud that i can't race him until the END of the day cuz i put a new belt on.

I WANT to like this belt, but i'm not convinced it's the best application for MY personnel sled.
To some guys, the XS fixes ALL their problems including low credit score, lack of libido or even cures cancer.

After this weekend, if this belt works good, the following week i'll put some high miles on to see if it will last.
I REALLY REALLY want this belt to work.

P.S: The "Cures Cancer" comment is not a claim, but rather a sarcastic comment from the Wise AZZ Clutchmaster SteveO

 

[RAMSOMAIR]

I'm not convinced yet either but always like to give things time instead of reaching conclusions immediately. Freshly tuned SW with Hurricane 225/240/270 tune that Yamamarc installed. Marc clutched for 8JP belt but I installed a XS825 right out of the gate. Marc advised to lighten up Dalton weights which I did and can't seem to pull anything over 8400-8500 rpm. Now I have only been on the trail with no long pulls and only have about 150kms so far on the belt. Weights are down to 3/8" set screw so only the 1/4" or nothing left to lighten them up. Now these RPMs were realized even on all 3 tunes. Again, no real long pulls and I believe I need to run it a bit more before jumping to any conclusions. Perhaps there is something else going on here but not sure. going to try the old 8JP today perhaps, once I clear all the snow.......FINALLY!!!

 

[sledding rocks]

the xs825 belt is a great belt for its strength and super clean , I have seen this belt on a sled with stm clutches , there again great , but a slow belt on top end by about 5mph vs the 8jp , so for me , great for the trail not so great for racing , a much slower belt on top end

 

[yamamarc]

I'm not convinced yet either but always like to give things time instead of reaching conclusions immediately. Freshly tuned SW with Hurricane 225/240/270 tune that Yamamarc installed. Marc clutched for 8JP belt but I installed a XS825 right out of the gate. Marc advised to lighten up Dalton weights which I did and can't seem to pull anything over 8400-8500 rpm. Now I have only been on the trail with no long pulls and only have about 150kms so far on the belt. Weights are down to 3/8" set screw so only the 1/4" or nothing left to lighten them up. Now these RPMs were realized even on all 3 tunes. Again, no real long pulls and I believe I need to run it a bit more before jumping to any conclusions. Perhaps there is something else going on here but not sure. going to try the old 8JP today perhaps, once I clear all the
[QUOTE="RAMSOMAIR,

I bet you felt like a kid at Christmas waking up to all this white gold eh!!!

 

[ClutchMaster]

Anyone one else try the ultimax on the team clutches and have poor results?
Last year I purchased the ultimax xs827 and had a 800 rpm drop and horrible performance. I contacted Timken and they sent me a new xs829 saying I had the wrong belt. (Awsome customer service)
I got out Thursday and had chance to get some good wot runs on a lake with the new belt and no luck . My rpm's were so inconsistent one run they dropped to 8300-8400 and the next run I was hitting the rev limiter and over reving. My first thought was something was binding in clutches. After talking with a buddy I decided to go back to the stock cat belt. We went back out riding Friday and Rpm's were perfect and consistent holding the same # each pass.
I decided I am just going to stick with the stock belt and not bother trying any other brands!

https://ty4stroke.com/threads/xs-825-shakedown.159164/page-2#post-1512080

Post 25

 

[ClutchMaster]

the xs825 belt is a great belt for its strength and super clean , I have seen this belt on a sled with stm clutches , there again great , but a slow belt on top end by about 5mph vs the 8jp , so for me , great for the trail not so great for racing , a much slower belt on top end

Only slower if you under rev, take out a lil weight and see what happens

 

[KnappAttack]

I've been testing the XS belt for 250 hard miles now, and I actually got to ride 100 miles yesterday with some fresh snow we received. I tested until I was blue in the face and wore the threads out of my clutches I tired so many different setups the last few weeks. I tried stock muffler setups, performance muffler setups and everything in between. I have the clutches running so cool and happy with the XS belt its silly, didn't ever think I'd find it with the SideWinder clutches, and had it not have been for the XS belt, I don't think I ever would have found the consistency on the big tunes. I've run it in warm and now cold temps and am confident it's going to work very well for me.

I'll say that Ultimax XS belt has saved me from driving my sled over with a dozer and crushing it. I've put the Winder clutches back on my sled and am actually planning to stick with them for the foreseeable future. I find the XS belt much more consistent, far quicker and faster speeds to a set distance. I haven't held it or found a spot to run the gears out yet, but don't see that it would be any different in top end unless its not turning the RPM. It actually shifts out farther on the primary than the 8JP. I have found I can now go back to light secondary springs using the XS belt and no longer need to use extra heavy secondary springs to keep a hold on the belt. I made 7 back to back passes yesterday on the BIG tune and belt temp is 145F, the inside sheave on the primary was 107* and the secondary was 90*. You just can't get any cooler and happier than that.

I've tried all types of tunes the last two weeks and too many clutch setups to count, my drill press scale got a workout testing primary springs and secondary pressures. I learned lots about the XS belt and the 8JP belt. I found using stock clutching on low HP tunes that there is not as much difference between the two belts, but more aggressive weights see more of a RPM swing between the two belts, the 8JP and the XS.

I was able to really lighten up all the pressures on the secondary and the primary for the XS belt.

If you are seeing inconsistent RPM swings on the XS belt I'd guess you are trying to over pinch it with too much pressure. Try backing off on the secondary pressure and primary weight. It will get the temps inline and allow it to shift up and down the sheaves like it should. And your primary rollers will thank you too!

Don't be afraid to try a lighter setup front and back, trust me, it will reward you when you get the balance right.

 

[sideshowBob]

KnappAttack
How long did you break in your XS825 before you started working it hard?

 

[Turboflash]

You guys probably all know this but I learned for the first time this year (# of brain cells is declining at my age) that breaking in belts is not just about 25-30 easy miles. 3 heat cycles are important. Timken engineer told me 3 heat cycles are more important than 25 easy miles. So, that's what I do now. Get belt up to at least 120 degF and then stop and let it cool all the way down X 3, all the while not doing any hard launches or WOT runs. I used to think just 25-30 easy miles was all it took.

 

[KnappAttack]

KnappAttack
How long did you break in your XS825 before you started working it hard?

I put 20-25 miles on it, let it cool off a couple-three times in there too, It RPMS really low early on even after break in, but then will come up and stabilize. I've clutched all over the board with it, had it as hot as 195* on a setup a couple different times, pretty much abused it, but have a nice happy setup in it now and it's nice and cool now with a balanced clutch setup.

I've been back and forth between the 8JP and the XS is hands down faster by a few MPH when clutched for and RPM brought back up where it needs to be, but be warned, you will be running lighter setups to get it right, and that may include getting a lesser base weight in the primary clutch and lighter springs in the secondary or in my case, both.

 

[Big_Phil]

the xs825 belt is a great belt for its strength and super clean , I have seen this belt on a sled with stm clutches , there again great , but a slow belt on top end by about 5mph vs the 8jp , so for me , great for the trail not so great for racing , a much slower belt on top end

All the radar run guys here run the 825 and say its the fastest belt.

 

[sideshowBob]

I put 20-25 miles on it, let it cool off a couple-three times in there too, It RPMS really low early on even after break in, but then will come up and stabilize. I've clutched all over the board with it, had it as hot as 195* on a setup a couple different times, pretty much abused it, but have a nice happy setup in it now and it's nice and cool now with a balanced clutch setup.

I've been back and forth between the 8JP and the XS is hands down faster by a few MPH when clutched for and RPM brought back up where it needs to be, but be warned, you will be running lighter setups to get it right, and that may include getting a lesser base weight in the primary clutch and lighter springs in the secondary or in my case, both.

Thanks again for all the info you pass on.

 

[ClutchMaster]

Looks like I’ll have too lighten up my setup, see if I can get those astounding belt and clutch temps you speak of.

 

[RAMSOMAIR]

I will leave everything as is then and get some more miles on the belt before I start ducking with the weights and springs!