Dne Ported Mxz 800

I have a 2002 mxz 800 done by DNE PERFORMANCE. I was wondering if anyone can help me with clutching on this sled? It has the rer secondary and I am willing to buy a non-rer secondary if that is any easier. I tried the clutching that they gave me,and I also called Bill Cudney at Cudney Racing and tried his set-up. With both set-ups the sled over-reved terribly.It should run at stock rpm's,but is turning anywhere from 8500-8600 on the tach.If anyone is familiar with this set-up I would appreciate any help. THANKS

Eagle, Post what you have and what you have tried and I'm sure you'll get some suggestions. Have you added weight to primary using adjustable pins? Are you running the updated RER spring or something custom from DNE or Bill? It will probably help to describe how you overrev - does it jump to 8500+ for shifting or does it slowly creep up there on long runs, etc. SummitAK

Sorry I should have listed that DNE's set-up was 280 ramps,200-320 primary spring,updated black secondary spring,stock helix and adjustable weights. Bill Cudney sold me his standard set-up for the mxz 800 and said all I needed to do was use the adjustable weight.His was a helix and primary and secondary springs.Stock ramps. Both set-ups would immediately fly up to maximum rpm which again on the tach was about 8500-8600. I am running the stock 127 belt and Bill told me that I needed to go to a dayco ultimax or a ski-doo 067 because the stock belt will slip.I did not have a chance to try this because we ran out of snow. Hope this will help one of you guys give me an idea where to go now.

So your saying it goes to peak then it over revs at the end or does it start creeping up right away, another words , from a dead stop you go wfo it imediately goes to 8000 but then does it start creeping out or does it pull at 8000,get to full shift and over revs. if it goes right away just keep adding weight until you get desired rpm, just a little thing too is you can get close right on the stand, make your change and then on a cherry picker or a real good stand ,crack it open and hold and watch the tach. and 800 will over rev at the end on the stand, but it can get you close at home then take it to the lake

The sled immediately flys past peak rpm.I have goodwin's adjustable pins and have filled them up completely with the same results.It does not go to 8000 and then creep up.It flys right past that and holds the rpm.

Whats Don have to say about it? He should be able to solve this for you.....

Eagle, You're saying that your shift speed for both kits is 8500+? It seems strange that both kits from these tuners would yield that much higher shift speed. Besides the clutches themselves the only thing in common between the two kits is the Goodwin pins. Did you purchase these from DNE or Cudney? I ask because I'm sure they are specifying the use of the "Heavy" pin kit. If you are using Doo's adjustable pins or lighter Goodwin pins you may be way too light. Have you weighed your pin/set screw combos or compared them to your stock solid pins - the Goodwins should be noticably longer? My guess is those guys were pushing you to the 18-20g range??? Some other things to check: Do you have a lot of miles on the sled? Possible clutch bushing wear leading to binding is something to check depending on mileage. Less likely is a tach problem, but most people find theirs typically read 100-150rpm high. Let us know what you find, SummitAK

The weights were brand new out of the wrapper from goodwin's.They have the paperwork stating which screws and what the different combinations weigh.You are right with the 18-20 grams.Both DNE and Bill Cudney said it should be somewhere around 18.5. The sled only has 2000 miles and when I had the motor done, it only had about 800 miles on it.

Have you adjusted your "clickers" also? The heavy pins from Goodwin should stick out past the arm if they are the heavies. Me thinks that you may received too much HP from DNE! Need to send some of it on like a chain letter. -Grover :D

My buddy has the same sled with the same mods.Dons kit with the 280 just didnt work,what did was 200-320 spring,stock ramps,i believe 301 with 20 grams with a 150-175 lb rider,18.7 with a 200 lb rider,updated secondary spring,with a straight 50 rer helix,27-43 gear.With this set up the sled really rips

Check your alignment, try the different belt (break it in first) and then keep putting the weight to the pins. You may have to melt a little lead and put that in the pins instead of allen screws. Sounds like Don did your motor just right to me. I would recommend getting a copy of the Skidoo race manual and read and re read the clutching section. There are a bunch of ways to lower your rpm-you can change the ramps or your primary spring or install a steeper (larger number) helix or maybe just simply click down. Good luck-whenever you mod a motor you usually need to make your own "clutch kit"

Eagle,just to give you an idea of how much work it was to come up with that clutching,we probably went through 5 or 6 helixs,at 130.00 each Canadian,and the same number of springs and ramps to come up with that combo,if you weigh under 200lbs I would give it a try.IMHO.By the way Dons porting kit was good for about ten sled lengths over the same sled,with shim kit,head,welded pistons,reeds and a modified stock pipe.His stuff flat works,it went from running neck and neck with a light mod f7 and stock zr900 to woopin them,even up top!!!

Thanks guys....John is that a straight 50 ski-doo helix or someone else's?

Doo!!

it sounds like maybe your secondary spring is binding and not shifting. go to the black spring as your only change to see if rpms drop as they should.

Both set-ups would immediately fly up to maximum rpm which again on the tach was about 8500-8600. ...I am running the stock 127 belt and Bill told me that I needed to go to a dayco ultimax or a ski-doo 067 because the stock belt will slip.I did not have a chance to try this because we ran out of snow. ---------------------------------- The sled immediately flys past peak rpm.I have goodwin's adjustable pins and have filled them up completely with the same results.It does not go to 8000 and then creep up.It flys right past that and holds the rpm. I would identify this as the culprit. As with my clutch kits there have been guys who come back and tell me this same thing nearly word for word. I go thru checklist with them and even listen to them add 4 grams more say than required. Same thing, Fries engine, high rpm right from the word Go! I ask them what belt number they have on... ...All guys come back saying another part number than stock. I calibrate with bone stock ramps/belt on the 440. Every owner with problem installs belt number required and the rpms come down. One guy even put on a wore glazed belt and rpms come down. Belt composition is amazing material. I would have more confidence in BC's kit and follow instructions to "T" just to rule out this belt issue. ...is it?...or is it not? Theory side to this, looking at the engine flying out the back door like you mention, this then I would say the belt is too hard and does not compress enough as it runs thru the primary sheaves. When torque is low as in this case with overrev, the primary temperature will be much higher than the secondary. In fact thru more runs I bet you would be able to spit on the clutch and it would bubble. If your engine is on its power then the torque having more push/clamping the belt will be higher. Rpms will be straight somewhat and temperature will be down. From my testing this complaint to see what it does for myself, I noticed that the outer sheave had great temperature difference "lower" than the stationary sheave when the right belt was on. When the wrong belt was on, both sheaves were super hot. Probaby 160 plus deg. On your checklist of things to do first off when season arrives is to rule out belt issue.

eagle17- I would go with John Breedons set up- just make sure you have the heavy pins- the stock belt works on my 200 hp triple- its just fine for your sled- with a 200/320 spring I would run 20 gram pins to start and run clickers 3 and 4 (with the 300/301 ramps) and of course the 50 cam and black spring- NOW if that set up works but the back shift is a little lazy go back to the purple sec. spring and retest-BJ BTW- my new 800HO cylinders will see Dons porting before the snow flies.