Recently, I've noticed a very hard engagement on my primary clutch. *I measured the free length on the spring (GP green), and it was about 3/8 inch shorter than it should be. *I contacted Goodwin, and they sent me a new spring free of charge. *Unfortunately, it didn't seem to change the engagement. *http://www.snowmobileworld.com/forums/iB_html/non-cgi/emoticons/confused.gif It's still very jerky at low speeds...engages at 4500, as it should, but disengages at about 4200 or so. *I clean the clutches about every 300 miles. *Anyone have any experience like this? *Any advice? *Thanks in advance.

What ramps are in it. Some ramps will cause the clutch to hang open then snap shut about the way you describe it.

Not sure if this will help, but they are GP-5 ramps...does that tell you anything? *The ramps have been in there all winter, and had about 700 miles on them before I noticed the hard engagement.

Some belts can really make the clutching feel different. I found the #127 very agressive compared to a Dayco or a #067

I'm not sure that the belt is the problem either. *It seems the same with the standard ski-doo belt, and the bombardier gold belt. *The engagement wasn't as hard with these same belts before.

Zog, check your bushings on your sliding half. *Although your sled is new it could be a fluke occurance. *I have come across this problem in several 670's over the years. Check both the inner and the outter bushings. Also check the casting cover for the primary spring, sometimes there is a heatcheck or a crack in the diecast die and causes a flaw or raised edge in the casting hindering the spring to rotate freely and to bind under compression, therefore varying the spring rate. *Just a thought.

Stockman http://www.snowmobileworld.com/forums/iB_html/non-cgi/emoticons/wink.gif

The mechanic at the local ski-doo dealer figured it out in about a minute...belt deflection. *Man, it's nice to have it engaging so smoothly again. Thanks for the input, everyone!