I will know more on this after today. I put about 75 miles on with stock gearing and a DP clutch kit and now have the 23/40 gearing in. I am going up to the lake this afternoon and I will post results later tonight or tomorrow. I will be comparing to a RX-1, another F7 and the Speedo. I saw 111-113 with the stock gearing in about 1500-2000 ft with a rolling start.
The clutched RX-1 is faster through out the runs but I am having a very hard time hooking up, even with the 170 1.25 studs. I think the double backer set up is not optimum for shallow snow or bare ice. The studs seem to not penetrate well. The other F7 has 140 (give or take a few) ice picks in the 5/8 lug camo speed track. This sled is unreal to 110 and pulled 118 in the same distance. He has stock clutching and 23/40 gearing.
Conditions on this lake have not changed in over a week so this will be a good comparison.
Just got back from the lake and had some interesting results. The RX-1 was still faster than me in midrange. Hook up seems to be most of it because I spin violently, even from 50 MPH. This lake has very little snow and a lot of bare spots. We were a dead heat up top. I was able to pull better top speeds with the 23/40 but only by 1-2 MPH. I definitely don't think the 23/40 is worth it for the trails.
We measured off three distances 1000, 2000 and around 3000 feet. In my earlier post I was running farther than I thought. I made most of my runs at 1000' or 3000'. Today in 1000 feet with the 23/40 i was mainly seeing 99 to 100 mph on the speedo. One run I did see 101. I then tried something a bit different. I changed to the D&D kit helix and kept the stock springs with the 62 gr. DP weights. This made a noticable difference. Sled pulled much harder and I was consistantly pulling 101-102 in a thousand feet and seen 2 runs at 103 (out of 6). I may try and put both helix's on a CMM and get the exact angles so I know where I'm at. I think the sled would pull even harder on top if I went to 60 or 61 gr. weights and loosened the secondary a bit. The highest RPM I seen (visual not tach recall) was 7750. I was running all day in the middle setting. I weight about 210 without the snowmobile clothing. I have the front shocks all the way loose, the front of the rear all the way loose, the couple blocks removed and the rear suspension all the way loose.
i just put in the gears a day ago...now i will see what the differnce will be this weekend ...ill let u know..ive done nothing to my sled besides change to the 23-40 gears..i was lookin for more top end with same holeshot..i have a benchmark to go by from running my F7 stock for a while...ill let u know..!
I just came back from a weekend of riding with my new gear set of 23/40
Most was high speed lake running ..the lakes had hardpack snow with very little loose snow on it.
I have DP clutch Kit, Carbon Tech Reeds, SW intake and the 23/40 gears
On the way north the sled only pulled 7400-7500 rpm and did see speedo speeds of 103-105...the temp was very cold -20 degrees Celcius....I felt the drop in RPM definately hindered my top end...I guess I was down 4-500 rpm that day...In a 6 mile lake run....yes 6 miles WOT the only sled that caught me was a 03 MXZ 800.
Now the next day, temp was the same and we lined up on the same 6 mile lake going south. There was about 8-10 sleds lined up for this one. At the start I took the holeshot on the field and never looked back...The sled ran 7900-7950 RPM but I was not able to read my speed due to sun glare and also being tucked under the winshield didnt help.
At the end of the 6 mile lake, I finished first 25-30 sleds ahead of the same MXZ800 that caught me the day before...a Viper third, probably another 20 sleds behind the MXZ then behind the viper came a 03 Pol 700 pro x another 10 sleds behind.
With this gear change I do notice a big loss in hole shot distance compared to other sleds I've run in the past and have taken a 5-6 sled jump on, now I'm down to a 2-3 lead the pull from there.
I dont know why I have the RPM loss the first day but will check the weights soon.
I did see 110 with the stock gears and clutch kit on a different river earlier and will have to take a run to the same stretch and compare to what I can get now with the gears and other goodies..
I will post the results in top end...
Hope this info is useful to someone...Maybe someone can help me out on why the RPM loss the one day..
I would guess if the motor was going to grenade , it would have done it either day...2 times 6 miles of WOT...It sounded good to me!
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