Snowmobile gearing help please

[jayjay283]

I have an artattack snowmobile, using my calipers its geared 13 Pinion 68 spur in 32p..( belt driven) .. it has no diff off course so I dont know what the end result will be... The drive pully (i suppose it called) that runs the track, is a 56t spur size. Anyone have experience with this. I have a 1515 1y or 1515 1.5d to run it with but is this way too slow ? I need a 5mm shaft for the nitro pinion thing to fit on and all my high kv motors (3000 kv+ are 1/8th) will it do 40 with a 1515 1.5d or should I buy say a 6xl ?

[What's_nitro?]

Well 13/68 gives you a 5.231:1 ratio. If there are no further reductions, then that is your final drive ratio. The 1515/1Y is 2200kV. If you run the maximum recommended 6s LiPo on that motor you'd be looking at ~49000 rpm unloaded, at the nominal voltage. That means your tracks would be moving around at more than 9000 rpm. That is pretty fast. Even with a lot of "rounding down", and assuming the drive cog is 2" in diameter, that puts you over 50 mph.

[jayjay283]

you da man. moving project "snow bunny" ahead.. Thanks.. Just didnt want it going 12mph and burning out the motor and esc in 5 min


whether this thing can take a 1515 will "to be seen" LOL its plastic but full bearings, I give it a 70% shot

[What's_nitro?]

If you want, take the actual diameter of the drive cog (not in cluding the teeth) and use it as "wheel size" in BrianG's speed calculator. You can use that to play around with different motor/voltage combinations.

Your 70% may be to much. That tread belt puts a lot more torque stress on a drivetrain than a wheel does.

[jayjay283]

that is a brilliant suggestion to a retard, if I just did it 13/68, 1:1 and 52mm tire circumfrance that would cover it right, nice

[What's_nitro?]

52mm tire diameter. That would cover it. Yes, nice.