the belt in the picture with the reddish underside is the MBL belt. they have always been specifically OEM only. they already build the polaris belts, as well as can-ams belts. they have two compounds now at the top of the list, both of which polaris uses in different machines. if MBL had something that was 30% stronger, held more heat, and was better, polaris would already have it, or so it would seem.
there are companies that are making belts that are harder. we have tested with them for almost two years with some of our race teams. the clutching that worked perfect for the OEM MBL belt wont work for the harder belt. we had to change calibrations to apply more clamping force to make the clutch hold the belt adequately. with the added pressure required to hold the belt tight to keep it from slipping increased the friction on the belt and sheaves and causes more heat and also gives more wear to the clutch faces. this race specific belt, although its insanely hard, and holds high heat well, does work and has helped this team win many races BUT the clutch calibrations had to be completely changed to hold this harder belt to keep it from slipping and the clutch intakes and exhaust had to be changed to aid in more air flow to get rid of the heat generated by the added friction.
will a harder belt work, yes. but i dont think MBL has been working on a harder compound. the only one that comes to mind that could be better is the compound MBL used in the 3211180 belt for polaris. Polaris used this belt in the 15 model XP1000 and claimed it had higher heat tolerance and was stronger. in fact it was harder, and took a different calibration to hold it adequately and it would slip like hell when the belt was cold. i never liked them and i do not use them at all. i am not saying this is the same compound that Trinity is using but its the only one that comes to mind that could be used because the best compound that MBL has, is already being used by polaris in their OEM belts.