EVO 25/45 gearing install went smoothly no issues. The top gear is wider at the small engagement cogs to better engage. I like that. Yamaha chain. I like that. Dont trust a cat chain. Perfect.
Got up early Sunday in Muni trail was groomed and hard as a rock. I do not have studs. I did not touch the clutching. Was setup for the Gates 8JP equivalent which pulled 103mph GPS on river. Just changed gears to 25/45. Had no problem at slow speeds loading and unloading sled. Sled did take longer to get up to speed. But wow was it speeding. I did see 108mph for quite a ways with flashes of 110. Bad news is the GPS which we all agreed upon to use as our guage read the dreaded 101mph. Primary clutch shows shifting using 8JP at those speeds at 1 in below top. Removed 8JP Gates and installed Dayco XTX which is 8DN length. Removed 7.8g from Primary which is slightly more total weight than I normally run using the XTX belt and put secondary at 6/1 . Same speeds 100,101 GPS. The GPS doesnt lie and makes you hold the speed. If you see it on GPS you will be able to do it again unlike the Speedo which doesnt take into account other factors.
So conclusion for this year is that gearing is very usable even with 8Jp length. The 8DN length setup helped the FUN factor but more work would need to be done if you want a spunky sled which I like. Very livable though and smooth. I then ran this gearing for over 500mi of the nastiest late season conditions I ran in a long time. On smooth very wet snow. It was raining. I could get 95mph pretty easy. Potential is there. Pretty happy and something to work with next year. Did the GPS screw us? Maybe maybe not but is what we all have been using so is what it is. I do believe we all will get those high speedo readings next year. Never saw those before. Just have to satisfy the GPS!
Got up early Sunday in Muni trail was groomed and hard as a rock. I do not have studs. I did not touch the clutching. Was setup for the Gates 8JP equivalent which pulled 103mph GPS on river. Just changed gears to 25/45. Had no problem at slow speeds loading and unloading sled. Sled did take longer to get up to speed. But wow was it speeding. I did see 108mph for quite a ways with flashes of 110. Bad news is the GPS which we all agreed upon to use as our guage read the dreaded 101mph. Primary clutch shows shifting using 8JP at those speeds at 1 in below top. Removed 8JP Gates and installed Dayco XTX which is 8DN length. Removed 7.8g from Primary which is slightly more total weight than I normally run using the XTX belt and put secondary at 6/1 . Same speeds 100,101 GPS. The GPS doesnt lie and makes you hold the speed. If you see it on GPS you will be able to do it again unlike the Speedo which doesnt take into account other factors.
So conclusion for this year is that gearing is very usable even with 8Jp length. The 8DN length setup helped the FUN factor but more work would need to be done if you want a spunky sled which I like. Very livable though and smooth. I then ran this gearing for over 500mi of the nastiest late season conditions I ran in a long time. On smooth very wet snow. It was raining. I could get 95mph pretty easy. Potential is there. Pretty happy and something to work with next year. Did the GPS screw us? Maybe maybe not but is what we all have been using so is what it is. I do believe we all will get those high speedo readings next year. Never saw those before. Just have to satisfy the GPS!
sixstringorsnow
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Unfortunately the 1.80 ratio may not work and give you inconsistent clutching affects with different conditions worse than how the sled reacts now. I wouldn't have gone anything lower than 1.92 and that may be pushing it with this sled. I will be re gearing next season as I do to all my snowmobiles, but I am struggling with which ratio to use. 2.00 or 1.92 I am concerned with how the different conditions make this sled react. Also I am running the 1.6 cobra track so I believe I will be heading more to the 2.00 ratio. Strange how the gear swap changed the speedo output. Looking forward to hear more of your finding from your testing.
Gearing swap did NOT change speedo output. It is what it is. Maybe GPS doesnt read as well in the woods or maybe track was spinning at 110mph? I dont know but gps is what I go by. You misunderstood. Clutching is if anything MORE consistent. Just the speed takes longer to get.
Nytros rule
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I'm running a 1.75 back country and at 1.95 I think I'm to tall, looking at 2.00 + HP, this thing is just anemic compared to the Nytro.
No doubt. It is a hp thing for sure. But from what I am seeing gearing taller does not make it worse. Just gives you more potential. At very least I dont have to worry about machining clutches anymore.
sixstringorsnow
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Sorry I must have misunderstood, I do have a touch of dyslexia. I still think 1.80 is to tall of a gear, I hope I'm wrong and it works for you. That is why Im interested in your results. I have been gearing all my sleds taller since my 93 XLT. Most people gear down. I have alway done the opposite from everyone else with great results, but you can go to far and have negative effects.
sixstringorsnow
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I was wondering if anyone could tell me if the 25/50 would fit with the 92 chain or would I have to go to the 24/48 to get my 2.00 ratio? I would rather use the 25/50 if I can.
According to EVO the 25t top gear fits stock chain.
sixstringorsnow
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If I was to replace the top gear to a 25 do I have to change anything else in the chain case? Like the other gears for reverse.
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I ordered the same set about a week ago still waiting.
I am looking to see if I can improve fuel mileage.
Nice report!
No nothing. I will confirm this in a week or so when I take it all apart again. I should have tried just the top gear myself while it was apart but never thought about it.
I would think you could do that by just clutching to say about 8500 rpm. Wont be as fun though!
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Cannondale, the woods like we talked about May have been the culprit as flying down trail 8 and 7 watching the same speeds, the gps showed more accurate. Not saying when we went out that the sleds weren't spinning the track, they were.... but were also crazy fast.
I have a video off Cannondale slipping and sliding with his boots on the trail.....was just like a frozen lake. The sleds were breaking thru the crust and were getting great hookup.
I have a video off Cannondale slipping and sliding with his boots on the trail.....was just like a frozen lake. The sleds were breaking thru the crust and were getting great hookup.
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Not worried Nos the speed potential is there I know it now. Never before have seen those numbers even if just a instant. Does not change the need for more power to get there faster and more consistently though. Still about 5 mph short of my goal. I wonder how much $/time that 5mph is going to cost if EVO doesn't figure out the ECU?
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Good post and info Cannondale27
