NOTE: On Dec 5th I spent a 1/2 day at Dynotech in Batiavia NY to run the new 800R on the dyno with stock and some tuned pipes. We were the 9th 800R to get on the dyno, just after Chuck Hamrah [Chuckaroo] got off spending his 1/2 day. After Jim having 8 800XP's on the dyno, Jim said that "the pipe needs to be hot for the engine to produce the power the engine is capable of". All the engines made from 151 to 153 hp depending on how hot he made the pipe get with some warm up runs.
I personally know that my 800R, I leave the garage I can go do a 600 foot run and my engine only turns 8000 rpms on the tach. After I return to the garage and go make another 600~700 foot pass, the pipe is hot, my engine runs at 8300 rock solid with the weight I have in the primary clutch.
Here are the theoretical speeds per gear ratio @ 8150 rpms.
21:45 (2.14) 82mph 99mph @ full o.d.
20:45 (2.25) 78mph 95mph @ full o.d.
19:45 (2.36) 76mph 92mph @ full o.d.
23:49 (2.13) 82mph 99mph @ full o.d.
22:49 (2.23) 78mph 95mph @ full o.d.
21:49 (2.33) 75mph 91mph @ full o.d.
20:49 (2.45) 71mph 86mph @ full o.d.
19:49 (2.57) 68mph 82mph @ full o.d.
Example:
21:49 (2.33) 75mph 91mph @ full o.d.
A rider is getting 47mph track speed and is complaining about his belt not going up the primary clutch....
The rider knows he can get 80mph out on the road to get to the powder but can't figure why the belt won't go up the primary in the snow.
Ok then - Why is he only getting 47mph track speed in the powder? Is it because of the snow load the sled is up against? Yes or No?
Is the snow load heavier than the load the sled see's on the road? Yes or No?
In the heavy snow, did the clutch system hit "equilibrium"?
Equilibrium - A condition in which all acting influences [engine power applying load] are canceled by others [sled/driver/elevations/snow load], resulting in a
stable, balanced, or unchanging system.[belt not going higher in primary]
So if the load is heavier in the snow, how can the belt possibly climb the primary? Would the belt climb the primary if the load was lightened - Load lightened as if the snow depth was reduced?
Equilibrium:
...A condition in which all acting influences [engine power applying load] (unchanged 8150 rpm)
...are canceled by others [sled/driver/elevations/LESS snow load],
...resulting in a stable, balanced, or unchanging system.[belt going slight higher in primary]
IF the snow load is less...
THEN would the point of the system reach equilibrium at a higher shift point? yes or no?
I can tell you that if the clutch is marked with dye, that at 47mph the belt will not wipe off more than 1-3/4 ~ 2" from the crank stub.
The only way the belt will go higher is if you;
1] Apply a mechanical reduction - Gear lower allowing the belt more travel across the sheave surface per the load it sees.
or
2] Run against less snow load to allow increases the track speed.
Any lower ratio will enhance the acceleration by reduction against the load the sled will see.
IF in a heavy load you don't think your belt is going high enough in the primary clutch
THEN gear to a lower ratio.
Lower gearing will let the sled have stronger "Holding power"
Holding Power - Under wide open throttle; The capacity to maintain track speed as load increases.
I personally know that my 800R, I leave the garage I can go do a 600 foot run and my engine only turns 8000 rpms on the tach. After I return to the garage and go make another 600~700 foot pass, the pipe is hot, my engine runs at 8300 rock solid with the weight I have in the primary clutch.
Here are the theoretical speeds per gear ratio @ 8150 rpms.
21:45 (2.14) 82mph 99mph @ full o.d.
20:45 (2.25) 78mph 95mph @ full o.d.
19:45 (2.36) 76mph 92mph @ full o.d.
23:49 (2.13) 82mph 99mph @ full o.d.
22:49 (2.23) 78mph 95mph @ full o.d.
21:49 (2.33) 75mph 91mph @ full o.d.
20:49 (2.45) 71mph 86mph @ full o.d.
19:49 (2.57) 68mph 82mph @ full o.d.
Example:
21:49 (2.33) 75mph 91mph @ full o.d.
A rider is getting 47mph track speed and is complaining about his belt not going up the primary clutch....
The rider knows he can get 80mph out on the road to get to the powder but can't figure why the belt won't go up the primary in the snow.
Ok then - Why is he only getting 47mph track speed in the powder? Is it because of the snow load the sled is up against? Yes or No?
Is the snow load heavier than the load the sled see's on the road? Yes or No?
In the heavy snow, did the clutch system hit "equilibrium"?
Equilibrium - A condition in which all acting influences [engine power applying load] are canceled by others [sled/driver/elevations/snow load], resulting in a
stable, balanced, or unchanging system.[belt not going higher in primary]
So if the load is heavier in the snow, how can the belt possibly climb the primary? Would the belt climb the primary if the load was lightened - Load lightened as if the snow depth was reduced?
Equilibrium:
...A condition in which all acting influences [engine power applying load] (unchanged 8150 rpm)
...are canceled by others [sled/driver/elevations/LESS snow load],
...resulting in a stable, balanced, or unchanging system.[belt going slight higher in primary]
IF the snow load is less...
THEN would the point of the system reach equilibrium at a higher shift point? yes or no?
I can tell you that if the clutch is marked with dye, that at 47mph the belt will not wipe off more than 1-3/4 ~ 2" from the crank stub.
The only way the belt will go higher is if you;
1] Apply a mechanical reduction - Gear lower allowing the belt more travel across the sheave surface per the load it sees.
or
2] Run against less snow load to allow increases the track speed.
Any lower ratio will enhance the acceleration by reduction against the load the sled will see.
IF in a heavy load you don't think your belt is going high enough in the primary clutch
THEN gear to a lower ratio.
Lower gearing will let the sled have stronger "Holding power"
Holding Power - Under wide open throttle; The capacity to maintain track speed as load increases.
