Ride motorsports in Woodinvill, 102.00 with tax for the 383 belt. I guess it's the updated belt for the 377.
Thats what they told me.
Did they use vasoline?? becuase that the first I have heard of a 383 belt??? I wonder if it's the same belt that 383lbs800 uses
Edit: Just found this....sounds like the 383 is a "close tolerance" 166.
"Lets try to rule-out some problems - At least try to eliminate or exclude something from consideration.
Fun reading for techy-types
166 BELT
IF you have been seeing fluctuating rpms with the 166 belt, then first start by calibrating the [Pulley Adjustable Knob]
With belt installed - TURN THE KNOB ALL THE WAY OUT TO LOOSE AND LET IT SHOW 2~3 THREADS.
WITH 2 HANDS, SLIP THE BELT THROUGH THE SHEAVES, TURNING THE BELT CLOCKWISE AND ALLOW FOR THE BELT TO CLIMB TO SIT AT THE RIM OF THE SECONDARY.
TURN [Pulley Adjustable Knob] CLOCKWISE IN UNTIL IT TOUCHES THE HELIX, TIGHTEN 1/8 TURN - TIGHTEN INSIDE LOCK NUT 4 FULL TURNS.
With any 1-3/8 [1.375] belt this will allow the least amount of belt deflection however it may be.
The wear limit for the belt is 1.366
Once you get down to the wear limit you'll probably start to see enhanced rpm fluctuation - any narrower belt will cause a fluctuation, even if you reduce flyweight mass.
The point of the comments above is to get you the tuner to calibrate the sled the best it can be with what you have at hand. IF you have this belt, THEN at least perform this procedure so it will help reduce amplitude of rpm fluctuation.
belt_width.jpg ( 43.21K ) Number of downloads: 18
377 BELT
The 377 belt is around 1.460 inches wide, not the 1.5 that people are hoping for however it will be wider than the 166. BRP actual widest belt width i've ever measured is 1.480 inches. The wear limit is the same 1.366 inches. This is .114 inches to play with. In the past I fanatically measured belt width when I ran the trails and off trail, at that time I did about 50/50 on/off with a 1.25 track. It seemed the average out was .010 of wear for every 100 miles (160 km) then you should be able to get 1140 miles out of a belt then change at the wear limit. I could get 1000 miles out of a belt without destruction and was happy with that.
IF you were to have your system calibrated fairly good with stable rpms using the 166 and go make a run, return to the start point and change out to the 377; You'll notice quicker engine response and under sustained throttle position like say you are doing 45mph going up the trail...you'll observe slight higher rpms at 45 mph with the 377, you'll see lower rpms with the 166.
The reason is that with the wider belt the TRA lever will be in a lower position than the 166 belt.
The center of gravity will be closer to the clutch shaft centerline.
A principle of operation is - IF a center of gravity of the arm is tucked closer to the clutch shaft centerline - THEN the engine will have to produce higher rpms to provide up shift.
With the center of gravity closer to the shaft, the rpms will have to increase to produce up shift.
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With quicker shift rpms on the trail, this will also reveal higher "shift rpms" under load. It will provide an improvement of maintaining stable rpms under load. [Holding power]
Do you ever find that when with the 166 belt it runs great and then as time/miles go on the performance of "rpm recovery" starts to diminish?
You can measure your belt and know that this wear is reducing the backshift performance.
Notice that with the wider belt [Yellow line] the sheaves would be apart more, if the sheave is apart more then the TRA lever is at a closer point to the clutch shaft center.
A principle of operation is - IF a center of gravity of the arm is tucked closer to the clutch shaft centerline - THEN the engine will have to produce higher rpms to provide up shift.
If the lever is at a closer point to the clutch shaft...the rpms will be higher.
If you are using a measuring tape with millimeters (mm) then know that (1mm = 0.039") 1mm = approximate 40 thou.
To be less confusing round up to .040 Forty Thou.
So if you ever hear or read 1.5mm that is .059", round up to .060" Sixty thou. If you ever read or hear 2mm, that equals .078" and round up to .080" Eighty thou.
383 BELT
This is a real simple explanation - The 383 belt is what the 166 belt "is supposed to be" -
I have had 166 belts with orange letters that came in at 1.45, 1.46, 1.48, just as wide as many of the race belts. When the white letter 166 was dumped on the market (different manufacturer) these came out ground in shape at literally .010 from the wear limit - A usable 100~200 miles then toss away for another $150 belt.
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Speed. If you have a bunch of belts, with a seamstress measuring tape measuring_tape.jpg ( 6.95K ) Number of downloads: 9
measure the circumference around the belt. In a speed run, a longer belt will produce more mph at top end than a shorter belt - and you may read otherwise, however running a longer belt is one of the oldest speed run tricks in the book. Without trying to sound like im reading a resume or I ran to school uphill both ways, I explain my observations; I did testing with dayco belts during watercross back in the 90’s. After chatting with an engineer about them having the same durometer, I picked that belt brand to use – and because I was getting free belts to test with. I ran belts for skidoo's and yamahas on skidoo's and every time a longer belt was installed, (changing nothing in the system except the belt) a higher mph was achieved. I ran a yamaha belt from an Ovation that flipped over at full shift it ran right out of the primary. Prior to that flipping, the sled mph like crazy. Go back to shorter belt, lower peak mph, go back to longer belt, higher mph.
Now don't go out and get a longer belt because you think it may help you in a drag race or speed run, it probably won't. Because of the excessive height in the primary, as an analogy, you would be starting out in 2nd gear and not good acceleration - but if you are doing a flying 1/2 mile out on the lake to where you can get over 100mph for sustained moments, then a longer belt is fun to use, you will mph, but you have to get past the point of poor acceleration in the low ratios and that takes "track length" so a lake or runway to test is in order.
The belt rides higher in the primary. The belt in the secondary is more distance away from the center of the secondary, in a more efficient location away from the center of the secondary. The belt has more arc area of contact in the primary pulling the belt with higher speed, the belt in the secondary is being clamped by the secondary harder at a larger radius.
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In the end, put whatever belt you run on whether it be stock or aftermarket. Perform proper belt deflection so that your track does something like this..."