I pull them off and clean them after every 100 miles or so. Same with blowing out the clutches with compressed air. (as hot of water as I can get...little dish soap...little bleach....soak and then scrub with a scotch brite pad. Prior to reinstall...a little acetone on a cloth wipe down of the clutch faces and a quick once over again with a scotch brite.
Normally get 1500 hard core mtn miles on 155 track 800 twin pipe app before I notice some performance drop off. That belt goes to the clutch cover as the back up there after.
Other tips:
pre-clean brand new belt prior to install
belt seasoned initially on the stand at home (just a few minutes of variable running will heat lock the compound, and micro align the belt to the sheaves if your clutches are properly tuned this is important)
prior to ever running a sled (team secondary esp) after a belt install it's important to hand roll the sled so that the belt is grabbed by the secondary as well as it can prior to actually engaging. (belts glaze instantly) Also if you can lift the rear of the sled and remove some resistance on that first engagement you can keep a belt from glazing or slipping.
Sleds never roll out of the shop, trailer, or trail without a few squirts of liquid wax on the hyfax and clips. Sleds never head off down the trail from the parking lot without generous snow loading of the entire suspension even if you have scratchers. (hmm how do I get 2000-3000 miles on no bogie wheeled long track mtn sleds without having to replace common hyfax when we ride full out on a minimum of 6 miles of hard packed trails getting to the goods over 50 times a year?)
Glaze a belt with a stick, slow awkward sled loading, or a weird reverse situation just clean and follow this sequence and they will last a long time and give you consistant high performance.
Easy to tell when a belt is failing even it visually appears fine. Unexplained change in engagement RPM or loss of top end RPM on a groomed trail. Simple!
Background from reference:
Once upon a time, way back in the day, I was a factory supported (er ah how do the DB, jealous, I don't get free stuff, or paid to ride snowmobiles guys on SW, so I hate say it?...Oh ya "sponshured") racer and prototype spec tester for Carlisle complete with stickers, apparel, banners, and everything! (Braaaap) Now I pay for belts so we take a lot better care of them.
