03-900 Std 24/39 gearing due to reverse. Anyone try an orange/white primary spring to prevent the overshift and subsequent belt spitting at WFO that you get with the purple? :0: Thanks, Austin

Go to Am snow and ask big al..........The guy knows it all

Have done that. He says it will overrev. My mechanic disagrees. Just curious before I make the change. But I'm not sure if Al knew I have 24/39 gearing before he answered, don't know if that makes a difference. Austin

Austin
What exactly do you mean by belt spitting? I don't think my sled overshifts either. I have a new ZR9 with reverse and the dam 24/39 gears. I was in the case last night trying to put a 25 in but it is not going to happen. I was hoping the 1100 miles on my sled would have stretched the chain enough to sneak in another tooth. We did some radar runs the other day and my sled was starting to overrev (7600+) at 111 on the gun. I could have gone faster with the stock gears. My clutching is stock except the driven has been loosened one hole to shift faster and pull the revs down a bit. It was revving 7400-7500 most of the time. I don't want to buy any clutch parts till I get my SLP pipe next week.

Terry

If you go with a spring that has a higher secondary rate you will raise your peak rpms. if you want to lower your peak RPMs there are a few things you can do. #1 heavier weights in the primary. Losen the secondary spring another hole. The other is the helix install one with a higher finishing angle. I'm not sure what you mean by over shifting... Does the sled bog down off the line or do you mean its "over reving on the top end. It would help to know what clutching you currently have to help remedy the problem.

Gearhead: They have confirmed with a stock 900 with the purple primary spring while WOT runs on ice the belt is coming right out the top of the sheaves. They did this with 2 consecutive belts. Apparently they did quite a bit of testing yesterday and said the orange/white is working well and pulling hard all the way through. I guess I'll find out tomorrow, as I am going to try this and see how it works out. If I find rpms are slightly high for shift point, can I correct this with the secondary, or am I then defeating the purpose? Austin SWRules

Your not going to overrev with the orange /white primary........there is only a 5lb difference in the finish rate........I have had the orange white in the F7 and the rpm's are so close that it doesnt show on the tach. I cant belive that the 900 it throwing belts because I never had a problem with my900........I guess they changed the driver to a10 tooth and the new gearing screwed things up......Its a 15 minuit change up and a 20 buck part just go for it

Thanks for the input sled-head. :D

ZR9 Something weird is happening if the belt is coming out of the sheaves. I ran my sled on ice flat out till it overrevved and the belt stayed on. The spring does not prevent belt spitting, it is how far the sheaves close that could push the belt out the top. If you machined the inside faces near the hub it could spit the belt. Changing springs will have no effect unless you put one in so stiff you cannot close the clutches all the way. Who is talking about belt spitting anyway. Sounds to me like an incorrectly machined clutch.

Terry

Hey Sledhead hows the snow in your part of Sask?

Terry

Snow....whats that??. I have to drive atleast 2 hours east to get any. We have a skiff on the ground but everytime I think we are going to get started it melts away :angry: .......How about you?? Where are you located??

I am located in Edmonton. How about you? We have been up to around 6" a couple of times, but each time we get melted out. I think the best riding around here was in November this year! At least the lakes are frozen now and have snow on them so we can ride, do radar runs, etc. I am going to put an SLP pipe on the ZR9 to help with the low gearing problem I have with the reverse. The SLP pipe pushes the power band a bit higher which will hopefully help me go a bit faster. Where are you located in Sask? We are thinking about a trip to the Yorkton area maybe in the next couple weeks. You had a ZR9 last year didn't you?

Terry

I live in Regina. Thats to bad that you dont have any snow this year...I look on the weather network snow conditions and most of northern Alberta is brown.. Are you going to yorkton to sled? Iwould probably go a little closer to the manitoba border by Banito(spelling??)....or Hudson Bay area I think the snow is a little better. What kind of gearing do you have in your 900 with the reverse kit?? I heard Cat went to a 10 tooth driver and different gearing and it kinda screwed things up from last year.. Anyways if your comming up to ride let me know and I can keep you posted on where to find the good snow..

Stock gearing this year is 26/41. The only gearing available for 9's with reverse is 24/39. Not sure on the driver size, I have not counted the teeth. I think we will consider the Hudson Bay area. Any idea if there is any trails up there? I think I have a Sask trail map at home. Either that or we will head for Yellowstone again Boo Hoo. One riding bud wants to go east and one wants to go south. I think you posted pictures of your green long track ZR9 here a while back?

Terry

Sled Head: I looked it up at the dealer while there this am and the orange white has a 50lb higher finish rate than the purple. 290 versus 240. Anyway, put 100 miles on today with the orange white, and it pulls Way harder than with the purple, especially in the middle. The other guy that changed his, radared yesterday 113 in 1000ft so I dont think the change is cheating the top end either. Gearhead: What I think is happening is the purple is collapsing with all that torque at full load, and the secondary cannot keep up. I don't know, as I stated earlier I am Not a clutching expert, but I can say after today, this spring makes the sled work far superior than the stock setup IMHO. $20.00 fix with no downside that I have found yet. Austin :hallo1:

Sorry zr9er..........I was thinking the firecat because it has a yellow primary spring.........Its been a while since I have pulled wrenches on the ZR900. Well anway I am glad to hear its working for you....What rpms are you at ??

Hey gearhead there are lots of trails up there and they are marked like the highways.......I know the snow is always very good up there......Atleast when I have been there... that pic of my 900 was taken in that area last year.......

7550-7600 area. I am really kinda shocked the difference it made in response. Hey, I guess it pays to listen to a mechanic now and again. :p

zr9
Are you sure your sled pulls harder, or does it just feel more responsive. Many time a sled revving higher "feels" better, but is not shifting as fast and is actually accellerating slower. I would be surprised if your sled is pulling well at 7600. D+D tries to pull them down to 7200-7300. Have you seen the Livingston Arctic 900 dyno tests? My sled got quicker (racing my piped XC8) when I loosened the driven and the revs dropped a bit.

Terry

Thats a slight over rev.......take into account you tach could be out but you should still try to stay below 7500rpms....I would try backing off the secondary 1 hole also or try a cam with a steeper finish angle...

I forgot.......If you want gut the air box because D@D showed big gains just from that.......dont forget to jet up

Gearhead: If you read back thru my posts, that is exactly what I am trying to do is slow the primary shift rate. :0: And yes I am fairly confident that it is indeed pulling harder. The rpms, whatever they may be on uncalibrated tach, are exactly where they were prior to the change, or maybe up 100. I have seen Livingstons dyno reports. Did you see the jet sizes? These were done at like 60F. Sled head: I loosened the sec one hole, we'll see how that works. :)

I agree with the statement of the purple spring spitting the belts. I have 1200miles on my sled and have run the radar at 113 many of times. I have found my primary clutch has worn at the bottom and now the belt is going to high. What kind of top end are you getting with the orange/white.

I had the same problems with the purple spring what is your top end rpm with the orangewhite spring

About 7600-I would like to get it down a little, just haven't decided how I am going to achieve it. I have not radared since the change so I can't comment on top end speed, not really what I am after anyway, just looking for better accel. Austin