Actually what I said was higher gearing does not give more top end as long as clutches are working correctly. Higher rpm doesn't either. I can rev to 92,93etc and see exact same top end as revving to 9000. Higher rpm just makes more noise. Gearing does make those speeds more consistent. All the clutching does change getting to max mph but if your not happy with speed on top just add power or work on reducing drag.
jeff_yam
Pro
I have an LTX and my top speed is 100mph on absolutly perfect trail condition. I forgot to mention that I use 8DN belt with 46/40 dalton helix with machined spring pocket and COTC clutch kit. What can I do to achieve 105mph?
Airbox,can,tuner,ignition,header,tuner,clutch so your not hitting limiter and suck up limiter straps,get rear of sled to sag and then still have to find about perfect conditions for 105mph.
Studroes144
TY 4 Stroke God
Like cannondale just said, it all takes power! And the little tricks with suspension help but then you're taken my away from other aspects of the sled that make it such a great trail machine. I'm definitely a believer that some run a little better than others but I don't believe there's any true setup that's gonna make for a 100 mph machine any given day of the year other than a turbo. I always had the preference of freeing up the hidden potential that's lost in the skid/suspension. DuPont slides on mine for 4500 miles now and they still look new, extra wheels on the skid to help it roll easier, suspension setup softer so the rear says more, front shocks set softer to lower the approach angle of the track. All things that work for me, but I enjoy the nice plush ride on the smooth and slightly chopped up trails. When trails get rough I can tell my suspension is on the soft side, but for me that's a fair trade off since most of our riding is weekdays when trails are flat and fast. If I ride on the weekends I have the 2 stroke sled to pound on for the rough days.
Yup even with all that on mine I still don't go around saying it's a 100mph sled. I've seen more than that a lot but I have also seen it struggle to get 90 in crappy conditions. But all the other sleds are also struggling too unless Turbo. I don't even try running those guys unless it's really rough.
So many things can affect the top speed especially on n/a motor. Drag is the biggest though weather it's wind/air or sloppy sticky snow. My 14 turbo on ice track went 112 with mid height windshield put on the bikini went 115 dropped the front end 4" hit 117 on ice stock gears. Changed gearing and hits 124 on sloppy snow on rail grade now with full suspension being used.
Studroes144
TY 4 Stroke God
Another small piece of info to go along with this. Like we've said before, machining for overdrive is great if you have a lot of power and perfect conditions to achieve it such as ice or asphalt, on snow it's not the ideal setup. When I got my viper a cousin of mine got a cat 7000, same identical track length so in essence they were identical sleds with exception of clutching and gearing. Cat clutches are designed to have more of a shift range than Yamaha clutches, in turn Cat had their sleds geared lower. I'm sure the thought was that lower gearing meant quicker acceleration. That wasn't the case, my viper with taller gearing out accelerated the 7000 everywhere plus had more top end. Both sleds then got studded indentical and each had a clutch kit installed from the same manufacturer. Outcome was still the same. The lower gearing in the cat just acted as though all the sled wanted to do was just rev but never really loaded the engine or accelerated hard. I know not many on here care about arctic cats but if you do some research on the procross 800 sleds you'll find people talk about how fast the 2012 and some 2013's were. Some later model 2013's and newer sleds all got updated gearing which was all lower than what the 12's and early 13's were. Guys complaining that their newer 800's would only run 105 mph and upset because the 2012's with higher gearing could out accelerate them and pull 10 mph more on top end. I own one of the early 2013 cat 800's and I can tell you first hand that it accelerates quicker than the same exact sled that's 2 years newer with the updated (lower) gearing. My viper has had a turbo now for 3 years, first year on low boost it started with stock 24/50 gearing, then changed to 21/41 and soon after went 22/41. The taller the gearing I have to it the quicker and faster it got..granted there's more power there, but just using it to state that lower gearing doesn't always mean quicker and in some cases actually means slower.
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09nytro
TY 4 Stroke God
I have the big venom Kit in my sled , all I have is muffler and airbox !
Ran great would get 100 pretty consistently so I thought I would Machine the clutch so belt would get to the top and I would get more top end!!!
Well , best I could get out of it was 78-80 mph , plus I cut to much off the clutch faces , like double what nos said !!!
Ran great would get 100 pretty consistently so I thought I would Machine the clutch so belt would get to the top and I would get more top end!!!
Well , best I could get out of it was 78-80 mph , plus I cut to much off the clutch faces , like double what nos said !!!
Studroes144
TY 4 Stroke God
Are you sure there's not any binding issues that are stopping the clutches from shifting? The big venon kit comes with primary's shims correct? Do you have the correct amount of shims installed? If there are too many shims installed in the primary the primary spring could coil bind before the clutch shifts out completely and that will limit top speed, or if the primary clutch was all reassembled in a way that there is something stopping it from shifting that'd do it too..that is of course if you actually split the clutch to do the machining. Even if you machined more off the clutches than recommended that will have no affect on the sled at those speeds. As a side note, machining too much on the primary and/or secondary can have very bad results. If you ever do get in an instance where you have the power to shift the clutches into overdrive and the primary clutch shifts too far you can force the belt too far out of the primary and could be very bad! Best case scenario it breaks the belt and you're free rolling, worse case the belt can flip over and lock up the clutches and track. Machine the secondary too much and the belt can travel too low and if it hits the center hub on the secondary you can be pretty well certain the belt will blow every time.
Most of the guys having issues with that kit are not running Gates belt. I have never used that kit but if it was designed for the Gates which I believe it was then that is the belt you should run or the whole benefit of a pre tuned kit is thrown out the window. Belts can make a huge difference.
All you guys machining clutches have used a magic marker on both clutches to confirm you are fully shifted before doing all this clutch work??? I know for sure 1 thing. No amount of clutching has ever gained me even 1 mph. It has gotten me there much quicker or kept me off the rev limiter but even absolutely stock clutching will do 105mph GPS under perfect conditions and with a fresh 8jp. So unless power is there for more than 105mph I can't believe there is any benefit to machining.
Studroes144
TY 4 Stroke God
Good point, never thought of that. I have 2 totally different clutch setups with different belts that give very similar results and when I use the wrong belt for the weight/helix/spring setup the sled is a turd.
09nytro
TY 4 Stroke God
Well had to try it , I read where they claim 5 mph gain so I figured what the heck , now I know!
I'm runnning the ultimax 825 and any clutch kit can be adjusted to the belt compound
Right it can be adjusted for that belt. Try that before giving up on the kit. If you did the machining and kit at same time perhaps all that's wrong is the tune for that belt.
