he said walls and stroke.......eh huh huh huh [img]i/expressions/face-icon-small-happy.gif[/img] [img]i/expressions/face-icon-small-tongue.gif[/img]

 

53 gram weights sound wayyyy too light for that motor. I would think 55's minimum up to 58's would be a better choice.

 

Even now, I'm running 58's in my 300. I think I will be switching back down to 55's with the next step down spring. Once I light my tires up, it upshifts way to fast and easy.

 

I was too thinking that he needs to go with the stock weights and tune from there. Although 2 grams may not do what he needs. He might have to custom grind some, or go to a 10-56 to keep the top rpm down. I think it will rock when it gets tuned in, but the piston to wall clearance really bothers me bad.Bubba

 

.008" is quite a bit. Was this measurement done on a fresh motor or one that was tore down? It sounds as though it is the Aaen set-up, fresh. .008" is alot on a "NEW" motor.

 

Do like Bubba suggested, get on the phone with Olav. Get a copy of his highly recommended clutching manual also...GREAT INFO!!!!


Ken

 

You said manual,huh huh

 

Olav insisted on the clearance or it would sieze.

He said they sent the cylinder with .005, but when we told him .008 he said that was correct for that engine to allow for cylinder vibration (harmonics).

the clutch set up to his specs./everthing was set to his specs.

the engine revs to 7250 and holds shortly, then the longer you run the revs increase and stop at 7800 to 8200 according to digital tachometer. This depends on weight of quad to what rpms you'll run.

I always set my piston to wall at .003 to .004 and break in very easy, without troubles.
My other .040 over 400 polaris was set at .003 and still running with over 4400 miles on piston/rings/bore. (1995 400 trailboss or 400)

anyway anyone have 440 polaris??????????????????????????????[img]i/expressions/face-icon-small-smile.gif[/img]

 

Are you running the roller secondary by chance? Sounds to me that you dont have enough secondary preload. As the secondary clutch shifts out, spring tension is reduced as it is not needed. If it is too low it will slip on the top end and cause rpms to raise. You should stay on the target rpm of 7250 +- until the clutches have totally shifted out which will be anywhere from 800-1000ft. Then the rpms should start climbing slowly until it just wont pull anymore. But that would take aways down the road to happen and you probably wouldnt want to hold it that long. Most stock size forged pistons set at .003 clearance. My .140 as I said before is an 86.5mm and sets at .00425-.00450. It would seem to me that .005 would be right for you, but I am not going to go against what Olav Aaen says. He is the master of the variable transmission for sure. There is no one better anywhere, and he would be the best in your situation for helping you. I personally dont like the digital tach. It's easier for me to read an analogue tach for tuning. But the engagement and full shift out is what you need to know. I'm sorry I couldnt help you more.Bubba