ext preformance questions - Snowmobile Forum: Your #1 Snowmobile Forum

123upmichigan · 01-28-2006, 07:10 PM

hello all still playin around with the 94 ext here. i have a couple questions,
1. what is the proper peak engine rpm for this sled? on the average i am seeing about 7200 rpm max, this is on the side of a plowed road with ice on it. got whipped by a 96 mxz.
I replaced the gearing that was in this sled from 23 35 to 19 39 that helped alot, but when they redid this sled it was blessed with a 2000 zl roller secondary. then i also added a green white cat spring to the primary to bring engagment to 4200 rpm. I have a felling that possible my clutches might be shifting out to soon before the motor can carry the load, bein the motor runs top shelf just will not pull the rpm's. i was told that if i changed my wrap on the secondary that it would help this issue, but i am open to idea's. anyone have any? this sled is an 85 mph sled on the icy road and feel like it should do a touch more. thanks all in advance for the help

123upmichigan · 01-29-2006, 07:44 PM

anyone have any idea's?

**RJ Gleason** · 01-30-2006, 11:29 AM

engine size?

clutch engaging way too high and by incerasing the secondary tension you will get better midrange pull but sacrifice a liottle top end speed.

Check to see what the oem setup was and go from there.

123upmichigan · 01-30-2006, 06:40 PM

the engine is a carb 580, the sled right now has excellent mid range pull to it, but like i sasdi not sure was the peak rpm is supposed to be. i am seeing about 7200-7300 on the tach no more no matter what conditions. i thought this might be on the low side. and the 96 mxz that whipped me was a 440.

letitsnow · 01-30-2006, 07:38 PM

you need some lighter weights in that primary!! you should be pulling near 8000. take your primary apart and weigh them and go a couple of grams lighter. your gearing is 19 on top and 19 on bottom? there is no way that motor can pull a ratio like that.

123upmichigan · 01-30-2006, 08:56 PM

nope sorry bout the typo the gearing is 19/39 in the sled. also gonna get a timing light thrown on it tomorrow, kinda figured the rpm's were a bit on the low side but wanted to make sure

letitsnow · 01-30-2006, 09:07 PM

you will lose a decent amount of top speed with those gears, it will be a beast out of the hole though.

red firecat 600 · 01-30-2006, 09:07 PM

hey man the sled should be pulling abou 8000 to 8200. A couple of things to look at before changing the weights in the primary are to see if the weight bushings are bad, and check the rollers on the spider. if they are good then start changing weights around