Bigbluemachine
Pro
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- 2017 Sidewinder RTX LE
2011 Apex ER
Flat spots on all three rollers. Replaced. Nothing like doing the field testing for YamahaWell..if you tightened the secondary..it would have held the shift back..so..depending on many things..the end result would be lower belt speed..as one thing...
I just put a big number helix nickel plated on mine 146 track non turbo.......( I wanted to start at the extreme end) and wound the spring up..gained about 14 KPH ,,but not letting it rev ..next step..less helix.
Holds the rpm at least....OEM it dropped over a 1000 from peak..
I am wondering if my farmers dyno will work on a 4/ like it does a 2/
Hope the winter lasts ..I work slow these days..
Byam
TY 4 Stroke Guru
The Ultimax xs-825 is the best one for my SW....
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Doc Harley
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- '17 Sidewinder LTX SE
The Ultimax xs-825 is the best one for my SW....![]()
Why do you say that?
Byam
TY 4 Stroke Guru
Simply testing.... (8jp and 8dn yamaha, c12 in both lenght, did not try the xtx....)
1-no more belt dust
2-clean sheave
3- constant rpm even after 100miles WFO in soft and hot condition!!!!!!
4-very durable, belt look new...
I have a couple new yamaha belt waiting their turn in the garage...lol. I am gone bring them back to dealer and change them for the XS 825.
Enough testing i have my results, xs-825 is the winner
1-no more belt dust
2-clean sheave
3- constant rpm even after 100miles WFO in soft and hot condition!!!!!!
4-very durable, belt look new...
I have a couple new yamaha belt waiting their turn in the garage...lol. I am gone bring them back to dealer and change them for the XS 825.
Enough testing i have my results, xs-825 is the winner

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krm
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- sidewinder 850 mxz,850xrs 850xrs 900t22Mach Z
i'm running the gates now and it must be working as my rpm are now lower and speed is up .
snowbeast
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- yes
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- yes
Can I ask why,i don't have any miles on mine yet,but just have a bad feeling about all these reports of destroyed and broke in half belts,of all sizes and types,when I get mine back togeather,it will have a lot more power than it did stock,but I have had big hp sleds in past and had good luck with belts,so there is something going on here besides just the belt,but at any rate,what does this belt do for your sled that the 8JP or 8DN did not do?The Ultimax xs-825 is the best one for my SW....![]()
snowbeast
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Hi how did your sledding work out for you in maine when you came in? Were you able to rack up some good milage? Also is your winder finally getting faster,i understand early on your doo was much faster,are they running closer now?i'm running the gates now and it must be working as my rpm are now lower and speed is up .
snowbeast
TY 4 Stroke God
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- 2015 apex xtx traded for a 2017 sidewinder L-tx-le
- yes
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- yes
So where are you buying these and at what price? thanksThe Ultimax xs-825 is the best one for my SW....![]()
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Doc Harley
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Which belt ken?i'm running the gates now and it must be working as my rpm are now lower and speed is up .
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krm
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- sidewinder 850 mxz,850xrs 850xrs 900t22Mach Z
i''ll look and let you know tomorrow joe .Which belt ken?
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krm
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- sidewinder 850 mxz,850xrs 850xrs 900t22Mach Z
5 days 1536 miles .the sw is getting better ,over 1400 on it 3k on the 850 .the 850 is like riding a little kids sled after 500 miles on the sw .Still no top end on the sw ,but it's still a nice sled .I''ll boost it up this summer .It seems the guys with no studs are seeing the best mph ?Not a big deal .It does make a good spare sled for people to ride though as it does ride nice for as big and heavy as it is .Hi how did your sledding work out for you in maine when you came in? Were you able to rack up some good milage? Also is your winder finally getting faster,i understand early on your doo was much faster,are they running closer now?
Hammer Down
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Apex XTX 2012
I agree with KRM. 1400 mi all stock but 192 studs 105 mph groomed trail max. Not sure what conditions everyone are riding and seeing 120? Do I have a lemon? 0-90 great though.
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Doc Harley
TY 4 Stroke God
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144studs and 120mph on the speedo in horrible conditions.
There are definitely as many running 120mph as there are running 110mph, or less.
While I understand studs will slow a sled down. Don't spend too much time on it. That's not the problem.
There are definitely as many running 120mph as there are running 110mph, or less.
While I understand studs will slow a sled down. Don't spend too much time on it. That's not the problem.
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krm
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joe,gates 40c4313
Hammer Down
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Apex XTX 2012
So any thoughts on what could be the cause of poor top end? . Low and mid seems fine to me but maybe there is an issue there as well. Other than that 1400 flawless miles!144studs and 120mph on the speedo in horrible conditions.
There are definitely as many running 120mph as there are running 110mph, or less.
While I understand studs will slow a sled down. Don't spend too much time on it. That's not the problem.
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