Have a Goodwin clutch kit. The thing has awesome midrange. Now i need to tame down the transfer a little. Coupler blocks are on 3 already. Thinking about shortening limiter strap a little. Didn't get to much draggin done, but did smoke a 2002 mxz 600. Rpm was right on at 8350. .Put on 270 miles, very satisfied!!
I had my sled at the Goodwin Shop, they used the F7 sno-pro as one of two test sleds for direct comparison for stock, clutched and then I am testing the TPI adjustable air-box intakes. I have a complete stalker results that I can post later. The sled was dropped off with almost no miles on it. When I picked it up it had 36. The TPI valves made a 2 MPH difference in 500 FT. The sled did not have studs, coupler block were set on 3 for all testing. The finalized kit ended up being: primary spring (blk), 66 gram weights, custom helix, and secondary silver spring. I am not sure of the lbs per spring at specific measurements, sorry.
For comparisons, the other F7 sled had more miles on it compared to mine when testing started, and with that fact the other F7 was faster by 2-3 sled lenghts. However one the sled had some miles and was clutch it was compared to a REV 800 X (clutched) with breakin in chip completed. In this testing, the sleds were run on snow covered ground for runs that vary from 1000 to 1200 FT on smooth field. As Greg Goodwin said, between these two sleds they good shake hands for the entire run. again, both non studed.
I don't know if that is a good or bad result, maybe others have much faster sleds than mine. As for the TPI valves I will have more results as the season goes on. I plan on taking a trip this weekend for some trail testing. The 500 FT mph on stalker was 80 MPH with valves closed and 82 MPH almost 83 with valves open.
You can call Goodwin and verify if you would like, speak to greg, he personally did all the testing on my machine and the other F7 in the shop, by the way he also had the other F7 on the dyno he would also have that information.
I put a D&D clutch kit in my F7. Still breaking in the engine too. I ran some tonight on my lake and got 110mph with max Rpm at 8020. I then checked the distance where I was running and it measured a little less than 4 tenths of a mile. I also checked the run with my GPS onboard and it verified 110mph. I'll be running this weekend with some friends and will post the results ( ZR 800, Mxz 700, 900 Thundercat all sleds worked !!) Just a question, Does the Rpm seem right for my sled with this clutch? Later F7 TOM Cat
Factory clutching F7 Hp to track on dyno with cold pipe at 7750 RPM 77 HP With hot pipe , same set up 71+ HP to track . With Dakota Performance clutch kit with hot pipe at 7750 RPM will deliver 78 HP to track on track dyno.
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