ecopter
TY 4 Stroke Guru
arteeex said:
Your example doesn't apply in this instance. The complete weight of the sled is not on a scale. What you're doing by tightening the springs is redistributing the weight from other parts of the machine to the front; kinda like a teeter totter.
jf
arteeex
TY 4 Stroke Master
ecopter said:
I agree. It is exactly like a teeter totter. Assume the center of mass is at the fulcrum in this system. When you raise one end from horizontal there will be a shift in the weight toward the lower end attributable to a vector (sin(theta)( m*g)) in that direction acting thru the center of mass. As a fair estimate in a symmetric system each degree of difference will cause about 1% increase in the load at the lower end. Which means, in this case, if tightening the spring raises the front of the sled there is a slight decrease in reactive force at the skis.
If there is a difference in the way the skis interact with the snow at higher preloads I would suggest this is due to having less attenuation in the system. It's similar to jumping off a roof with your knees locked versus bent. Same loads, different response.
I sense a lot of poorly setup sleds are leaving the dealerships as is usually the case. The demos I rode had zero darting problems, so unless something changed by production time all I can see is setup. Remember that every change made affects other aspects as well as the targeted one.
IMO . . . a teeter-totter is a poor analogy because it only has one fulcrum point (along a single plane) whereas the contact area of a track on a sled has multiple points. Ski pressure is largely determined by the track contact points, but is also affected to some degree by the preload of the ski springs.
IMO . . . a teeter-totter is a poor analogy because it only has one fulcrum point (along a single plane) whereas the contact area of a track on a sled has multiple points. Ski pressure is largely determined by the track contact points, but is also affected to some degree by the preload of the ski springs.
ecopter
TY 4 Stroke Guru
you know what I meant
Can someone answer my question. To help with darting should i turn the nut clockwise and compress the spring or counter clockwise to lengthen the spring??
ecopter said:
Yes I did, and I should have done a better job of saying so, sorry.
I was just trying to point out that the balance of a sled is a little more complex than a teeter-totter, but the overall idea has similarities.
slimjim2525 said:
To increase preload you compress the spring. However, whether this will help darting or not depends on the rest of the setup.
Take all of Turks (and others' input). If you have time for testing - try them one at a time and then test culminating in all of them together. If not - just make all of the adjustments together and test.
SumpBuster
TY 4 Stroke God
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There's no easy answer for everyone. Myself, I set the front with minimal pressure, the strap so I've got transfer to just get the skis real light under power, and then the rest is where I am on the seat and throttle..on the tank gives more bite with feathery or off throttle (when you really must turn) or slide back. Sort of a balancing act. More ski pressure never worked for me..too much into the surface, and steering is hard and too much darting. For me, less ski bite is better. Curves lend themselves to my style pretty well. But I've made the stock skis work ok also. duallies will drastically reduce darting, but they don't turn fast enough when I need them too.
