XP123
TY 4 Stroke Master
- Joined
- Dec 25, 2016
- Messages
- 1,494
- Reaction score
- 1,437
- Points
- 958
- Location
- Chautauqua NY
- Country
- USA
- Snowmobile
- Sidewinder XTX LE 137
More stuff today boys. I have "regular" trail riding temps.
I will use stock set up tomorrow for final analysis.
I have come to some conclusions also. Yes the 8JP outperforms the 8DN, but i will have an 8DN as a third belt on me at all times. The 8DN with this last set up was soft on bottom, took a half second more to get up to 9000 rpm's & was 4 mph slower on top. It actually runs good & is hard to tell, but i had the 850 pull up to me & then i cut him loose. I would then chase him down judging gain rate & how long it took to over take him. I did this throughout the day. With 8JP it was instant. With 8DN it was not. BUT this belt ran cool at EXTREME riding & for most riding is very good. I'm assuming this belt will last a lot of miles.
Here are some numbers & will explain later.
My set up for today:
-stock with stock track & 96 studs
-165 pound rider with 30 pounds extra
-clutch center to center =262mm
-offset=60.5mm
PRIMARY:
-TP Orange spring
-HH weights with just aluminum mid 3/8ths bolt
-TP rollers & 911 adjustable cover
SECONDARY:
-TP Orange spring
-33/35 helix wrapped at 30
-TP rollers
-OSP adjuster
8JP with 650 miles on it this morning: "regular" riding freshly groomed & loose
Primary =105/ 95/ 99
Secondary=100/ 110/ 110
Belt =170/ 165 /170
RPM's =9200 then down to 9100. rode at 6000 to 7000 for most of these runs
8JP after 750 miles i went postal on this belt for 50 miles over 8000 rpm's
P=115
S=120
B=180
RPM's=9100 then down to 9000
Top Speed seen on speedo=99 mph
8DN "regular " riding
P=105
S=115
B=160
RPM=6000 to 7000
8DN going postal. This run was absurd.
P=125
S=150
B=160
RPM's=9000 down to 8900
Top Speed seen=94 mph
A couple of notes here. I knew i'd be over-revving & saw 9400 rpm's a few times, but i wanted to over achieve today & bring rpm's down later.
I tried some "regular" trail riding temps. I've been called a Hummingbird on Crack before so i don't do anything "slow"!
The 8JP pulls were hard pulls then i settled at 6000 to 6500 rpm's for 15 minutes thinking the belt would cool, but it didn't. The clutches cooled, but not the belt telling me maybe some vents are in order here.
The 8JP clutches were almost cold. 99 degrees? SERIOUS? If my mom used a Rectal Thermometer on me; i'd be going to school that day!
She still has that Thermometer by the way.
The 8JP was pulling hard. I mean scary.
At 750 miles & a BIG 50 mile run from Kakadjo to Pittson Farms up next, i tried to blow the belt. I beat it like a Red Headed Step Child! I ran five 4 mile pulls over 8000 rpm's. I locked up the brakes getting sideways then nailed it 3 times. I ran it off trail in deep snow for a minute pulling 9400 rpm's. I ran it full WOT for as long as i could safely. 2 moose & a gaggle of deer slowed this run twice, but i COULD NOT BLOW THIS BELT!
The last time here i GRENADED my first belt last year going half the speed. I gapped my friend so bad, after a Reeses, water, jerky & drained the vain he pulled up.
On the way home i abused the 8DN maybe even worse. I'm not proud of it...............well......actually i am.
ANALYSIS:
-i think some venting may help
-8DN still looks good & most will not notice the performance drop
- i can put on 8DN without the clutch tools
- i run 8JP even with top of sheave & 8DN just above sheave. This made both belts even on bottom end, but not today
-top speed still has me concerned although i don't think i could run any faster even if i could. 40 to 90 is absolutely VISCIOUS for a stocker!
TOMORROW:
Primary:
-stock weights
-stock spring with TP glide washers
-TP 911 cover & rollers
Secondary:
-stock spring
-TP rollers
-33/35 helix wrapped at 60
I will try both belts again, but this time i will try NOT to go Apeshit first.
I have a new 8JP for fair testing.
BTW: my Doo buddy's Etec has been broken so he rode my 'Winder for the day & the 850 for the day.........he just bought a Sidewinder!
Tomorrow i will post STOCK results.
We need more OCD guys on here like you and Dan!

I have been reading all the posts of guys trying different belts and I'm still on my 8JP with 2200 miles on it and it still looks great. I have very little belt dust and now cool running clutches. My clutches with the TP Orange secondary @ 3-3 and 33/35 helix was running very very hot.