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Discussion Starter #1
Hello All.  After porting my 01 Summit 700 and adding a set of twin pipes, I am looking to raise total top end rpm.  By using a set of solid pins on my magnesium arms and a light poundage on the top end of my primary spring, in theory, I should be able to pull more rpm.  Am I on the right track?  Any input greatly appreciated!
 

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Post the clutching specs you have in there now, then maybe someone will give you a set-up, or point you in the right direction.  
fallowing is a couple of little tips that may help
- lighter pins = more rpm(both on engagment and on top operating rpm, and remember a little makes a big difference) and the opposite for heavier pins
- heavier spring = more rpm, but you can get the different spring loads and use those to help you pic out a spring that will work for you.   lets say you have a 230/350(pink/pink) spring in there right now. you want a little more RPM, but you would like to keep the same engagment RPM. You could just put a 230/380(pink/white) spring in there

Ramps will also change the RPM at which your sled will run at. they will also change the shift characteristics too.

What type of set-up do you have in the secondary?
hope that helps a bit, if you need any more help just post it.
 

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Discussion Starter #3
My set up for right now is as follows:  299 Ramps, Bombardier spring, (160-350) Magnesium arms and solid pins.  My secondary : 47 Degree helix, Beige stock spring, Pulling @17lbs.  My engagement RPM is now a little low, coming in at @ 4200.  The top end is the problem in that even in clicker position 6, I am only pulling about 81-8200 RPM.  I am trying to spin the engine to 8400 on the top and would like to back down on the clickers so I will have some adjustment as conditions change.  I did try a threaded pin with two small inserts in them, but then the primary was not shifting out like it was before, but I did get a bit more RPM on the top. Maybe I made too drastic of a change at once, The threaded pin is way lighter, than the solid. I was thinking of trying the solid pins with a 200-320 with everything else the same.  Would that put me in the ballpark and still let the clutch shift all the way out?  Thanks for the help in advance!!
 

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what are you using the sled for, dragging or trail riding/lake running?
also seeing as how you are going from 7800 RPM to 8400 RPM, your gearing will also need to be a little different. you are geared for about 10 mph higher than you were when you were pulling 7800, that may be the reason your clutchs are not shifting the same try going one tooth bigger on top, the extra power you supposedly got from the pipes and such should be able to pull that, or it might even pull the gears you have now, once you get it set-up right..    Do you have acess to a gram scale?  you can take a little bit of weight off those pins(2 grams or so) and that may help a little.
also you have a purple pink spring in there, you should try a green/white(200/380) spring, it will bump up your engagement a few hundred RPM and your top rpm will come up a 2 hundred or so. if you change the spring, do not do anything to the pins until after you change it, then you may just have to take a very small amount off of them.

as for the secondary, i have had good luck with a 50/47, with a white spring @19 pounds

hope that helps, anything else just post
 

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If you use MAG arms you need to load it with pin wieght and or lighter finish on front spring. Do not lighter pin and do not increase finish. If you don't have heavy adjustable pins and you want to run the stock solids, then take finish out of the spring. Your probably getting a lot of heat in the primary= slippage. The light arms are fighting the high rate spring. In my 740 I ran a 160-230 spring and 21.6 gram pins, spinning 8100. You are on the right track but you just have to try it. It goes against standard clutching theory but it does work. Q's- traction? Wieght? Altitude?
 

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Discussion Starter #6
Thanks for the input.  I'll grab some different springs and pins and head for the snow.  I ride the back country near Cooke City, MT  Lots of boondocking and hillclimbing.  Not much powder this time of year though, just trying to get it close on the hardpack for right now.  Also I am geared 20-43.  I am not necessarily looking for top end MPH as much as just pulling 8400 RPM.  Thanks again!
 
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