I just ran into this information in a Gates Catalogue for both Snowmobiles and Scooter Belts (ATV's also). I thought there might be some interest in the content. I'd never seen this before.
“Break In†Instructions
All snowmobile belts yield better performance and
longer life if they are “broken in†under moderate
riding conditions. Gates strongly suggests the
first 10 – 15 miles of operation on a new belt
be at a maximum of one half throttle and with
speeds no higher than 50 miles per hour. During
the “break in†period, frequent shifting over the
entire speed ratio range is also required (ride so
transmission shifts often, without putting the belt
under extreme load). The “break in†procedure allows
the V-shaped belt to seat in and the side
walls to conform to the angled pulley faces. This
procedure minimizes the chance of premature
belt edge cord failure and leads to increased
belt life.
Gates - Belt Trouble Shooting Guide
Slow acceleration:
• Belt worn too narrow (when engine tuned correctly)
• Belt sidewalls glazed excessively.
• Pulleys or center not adjusted for belt fit.
• Pulleys not tuned to match belt construction.
• Clutch pulleys dirty or worn.
• Secondary gearing not correct.
Engine maximum speed too high:
• Belt sidewalls glazed excessively. during hard acceleration.
• Clutch pulleys dirty or worn.
• Pulleys not tuned to match belt construction.
Excessive vibration in drive system.
• Belt has spin burn spots on sidewalls.
• Pulleys loose on shafts or not properly mounted.
Clutch engagement rough or not at proper RPM:
• Belt too narrow.
• Clutch not adjusted to belt construction
• Clutch pulleys dirty or worn.
System not back shifting properly.
• DriveN spring not calibrated properly.
• Clutch pulleys dirty or worn.
Premature belt failure.
• Drive not aligned properly.
• Improper belt fit.
• Clutch pulleys dirty or worn.
• Clutch pulleys not adjusted to belt.
