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cb is melting spur.. why??

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beason

beason

Bash, Fix, Repeat..
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RC Driving Style
  1. Bashing
i was running my savy sunday and noticed that every time i stoped running it, when i would go back there would be a rough spot on my spur.. upon closer examination i noticed it was a melted spot most were just little rough spots but one melted pretty bad.. i have the xtm 24.7 engine, carbon 3 shoe setup with 1.0 (black) springs and when i had it apart last i hit the cb with 150 grit sand paper to take the gloss off, after the run i looked again and it seemed the gloss was back so i sanded it again. i did notice though that i had forgot a shim and the inner bearing was setting against a bigger shim that would alow both inner and outer races to touch it. cb spins free but has almost no play in it..could this be the problem?? am i doing something wrong?? it didnt start till the 24.7 but i did the sanding at the same time and replaced the shoes and springs.. i temped the bell once and it was 167 deg..
 
I had something like that happen, my cause was the brakes were almost constantly on and when I stopped running the savage the spur melted onto the cb...had to sand all the plastic off the cb!!!

Don't know if thats your problem tho...might be worth checking it out.
 
I would say that your gear mesh is too tight. I would check that first, friction creates heat, that would be my first check.
 
I burned two spurs before I realized the my mesh was way to tight. I also think you check that. Thats also the easiest thing to check.
 
Clutchbell isn't touching the spur gear is it?
I had that happen to me once, but the clutch was slipping. :shrug:
 
i thought the mess was ok.. ill check that.. the cb isnt touching the spur.. i dont htink the brakes are dragging but it was running sluggish.. but could have been becasue the backplate was backing off..
 
could be your clutch isnt holding the power of the engine well enough. if your clutch slips that builds up a LOT of heat, which can melt a spur. i killed 2 spurs in 15 minutes before i realized my CB was heating up because the clutch on the mill was done. going mudding was the culprit.
 
the shoes and springs were new.. i replaced all that.. maby there just not good enough
 
is there a chance that grease are on the shoes? Maybe you got some on them when they were installed?..that would cause them to slip too.
 
Last edited:
no grease i cleaned um up real good.. and blew out the bearings.. I'm using the 1.0 springs.. the black ones..
 
it was runnin sliggish but after shutdown i noticed the backplate had loosend up so that may have been the problem
 

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