(1)Primary clutch springs are listed in Lbs. Is there a conversion to tell what RPM the spring will engage at ?

(2) whats the differanc between a spring with low engagement and high shift rate VS high engagement and low shift rate ? etc ?

 

Boy, you are asking for a book my friend[img]i/expressions/face-icon-small-happy.gif[/img] The first number listed on a spring is the engagement pressure. The lower the number the lower the rpms will be when the bike starts to try and creep or move. The higher the number the reverse. The second number is the shift pressure. Basically think of it as the higher the number the more rpms the bike will produce at full throttle. The spring and weights are what will determine what rpms the engine runs at WOT. Now, that might sound easy in a way. The big problem is you need a good balance between what it engages at and how driveable the bike is. Just putting a bigger or smaller spring wont always help things out. A low engagement spring with a high rate will take off at a low rpm, but the rpms will raise quikly as more throttle is applied. A spring with a high engagement and a low shift rate will take off at a high rpm, but start shifting quickly without applying a lot of throttle. There is no chart that will tell what springs do for rpms considering that clutch wear, clutch alignment, belt wear,deflection, and most of all weights come into play to determine that. Hope this helps,Bubba

 

Ya I figured it was a thick book to, and knew you would be the first to answer. I,m just new to this clutch thing and trying to understand it.


Let see if I got it. This would be a better option for trail type riding,were it will make power and less speed ?

 

Well, it could be. The problem is that you need to keep the operating range of the motor where the pipe still makes good useable power. Let me make a suggestion. The best $30 I ever spent a few years ago was to buy Aaen's clutch tuning handbook. It took several times reading through along with some hands on to understand it, but it finally just clicked one day and from there clutching has been easy. By the way Wayne, I have several used springs in different styles that I would be more than happy to send you for trial and error.

 

bubba what springs would u happen to have???

 

Not sure without going up to the attic and looking. I have them stashed in a box somewhere. It's been a year or so and I cant remember exactly.

 

bubba i have read Olav's book twice now and am still trying to grasp a few of the concept but im getting there.

 

It really makes things easier once you get a tach hooked up and start playing around with changing things.

 

Bubba297,
Thanks for the offer, After talking to rick today, I'm going to try a few other things first with the spring I have. Trying to get it so there is no bog on hills and the power is there when you hit the throttle. What is your opinion on flywheel lighting ? I think it would help the throttle responce since it would have to windup such a heavy flywheel.

 

Whuggs, a lot of people including myself have done hours of testing with springs, different wieghts, different types of belts, and even tires. A few suggestions (or my $.02). As Bubba said, get the book and read it over and over and over. I even took notes after I started reading it the second time. Along with different springs, get a tach. I got one from autozone just to do my testing , then took it off after I was satisfied with the results. Before you do any testing of springs, make sure you got that thing jetted spot on from bottom to top. Also, don't forget, that adjustment on the rear shock spring can play it's part in helping those tires bite dirt too. Very few people mention the rear shock, but I'm a lite rider and it took me a bit of testing to get it right after adding on the mods. And last but not least, don't get sidetracted somewheres along in the testing faze and forget what kind of riding you're gonna be doing the majority of the time. I got kinda sidetracted when I was doing some testing and ended up with a 4X4 quad that had no problem smoking any of my buddies 4X4 quads in a drag race, but wasn't the best it could be when riding in the woods which is where I do the majority of my riding with them. Then I ended up going through the testing procedure all over again to get the best results I could for slower trail/mud riding(0-40mph). I don't have great top end now, but it hooks up and accelerates so well now, even in the muddy sections it's hard to keep the front end on the ground. Best of luck with the testing.