dumb-ish q on clutch shift-out

[motomikey]

i hear alot of guys putting black pen marks on the primary to see if they're getting full shift-out on a climb, but if your geared for say-70 mph top speed, wouldnt you have to be getting 70 mph track speed on a climb to shift fully out? doesnt seem likely with a 162 by 2 and a half track

 

[mod03rmk800]

IMO, this is a flatland clutching idea

 

[NoSecondChances]

i hear alot of guys putting black pen marks on the primary to see if they're getting full shift-out on a climb, but if your geared for say-70 mph top speed, wouldnt you have to be getting 70 mph track speed on a climb to shift fully out? doesnt seem likely with a 162 by 2 and a half track

It will tell you where your clutches are running (i.e. at 8000 rpm uphill, where is the clutch pulling to?) which IMO, is basically what you want to know, not necessarily full shift. Ideally (and this a very gross generalization with room for a huge amount of debate) if you can get the motor to full shift and hold RPM with the heaviest weights and the tallest gears it will pull, then in theory you are running the optimum (efficient) setup from a clutching perspective. However, so many factors play into this that this statement rarely applies. I use the line on my clutches method simply because it is an easy way to tell between runs what my clutching is telling me more about how they are running more than anything else.

I understand what you are saying about 70 mph with a 162X2.5 though.

 

[mod03rmk800]

Ideally (and this a very gross generalization with room for a huge amount of debate) if you can get the motor to full shift and hold RPM with the heaviest weights and the tallest gears it will pull, then in theory you are running the optimum (efficient) setup from a clutching perspective.


In deep snow I think that is an impossible set up to get without extreme belt heat. I have found on my 800 mod that once I get further than a 1:1 ratio on big or multiple pulls up big stuff, the belt gets hot and performance goes bye-bye. So to make my life easier I shoot for 1:1 ratio with the biggest gearing that it will pull. I am giving up on some track speed and some distance up the hill but I can hit them multiple times or a really long pull without the belt gernading at the wrong time. Concrete snow maybe possible or the big power sleds that can ride up out of the snow? But I doubt even then the heat problem doesn't exist as the belt has to endure the forces in the secondary.

 

[mattymac]

This technique is more for the trails than the steep and deep. Works great for 500/660 ft drag racing. I use this as a baseline to see exactally where I stand on gearing and how diffrent clutch setups affect clutch shift. It can be extremely benificial in alot of sircumstances IMO.

 

[Scott]

I've used it to see if my clutches shift out enough on a climb.

It IS a useful tool.

Found out this weekend that my primary was about 3/4" from the top of the sheaves...could use a little more shift out.

I will need to reshim the secondary, or change belts. That'll make the belt sit higher in the secondary and allow the primary to shift out and catch up with the secondary.

 

[winter brew]

It is just to see how far they shift, not necessarily if they shift all the way. I use it on a hill as I make changes to see if my change is doing what I need it to do....just another tuning tool.

 

[motomikey]

gotcha--thanks