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Motor shaft and pinion length gripe.

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biggman100

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I'm sure this has been posted many times, but here goes. Why can't manufacturers standardize motor shaft length and pinion gear length? I have a bunch of 32p pinions, and 3 15T motors, that I can't use because of it. The only way to use the motors I have is to buy pinions that fit the 12MM shaft length which I can't find, or, to use the pinions I do have, buy new motors, which I did, only to have the 2 new motors I bought (surpass Hobby 12T and HobbyWing 555 11T), be too short for the pinions I have. I either need a motor with a 15MM (which means Traxxas 12T, which I constantly burn up, or, Arrma 12T, which doesn't ever last with me), or longer shaft, or pinions that are 12MM or shorter in length, which I can't find. Currently, I can't afford another $100 HobbyWing brushless combo, which means the new Fury slider I just finished sits for who knows how long, unless I rob the HobbyWing combo from my custom Senton project, and then that sits for months.
 
The biggest reason for this whole thing, I don't want the new Fury brushless. Every time I end up with a brushless 2WD, it's nearly undrivable, because all it does is spin out and do constant donuts, so, I would prefer to keep it brushed. And, yes, I know I can go with smaller pinions to lower the speed, but, even that never works, because I run on concrete a lot. I have 3 trucks with HobbyWing Quicrun G2 combo's, that include the 10BL120, and a 4000KV 3652, and, even with a gyro, and 9 to12T pinions, not a single one of those trucks will go straight most of the time.
 
With the pinion installed on the 15T motor, the grub screw is literally right at the end of the motor shaft. The end of the motor shaft is 4MM from the end of the pinion, and, the center of the grub screw is 4.3MM from the end of the pinion, so, let see how long it takes before the pinion comes off, even with Loc-Tite.

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The biggest reason for this whole thing, I don't want the new Fury brushless. Every time I end up with a brushless 2WD, it's nearly undrivable, because all it does is spin out and do constant donuts, so, I would prefer to keep it brushed. And, yes, I know I can go with smaller pinions to lower the speed, but, even that never works, because I run on concrete a lot. I have 3 trucks with HobbyWing Quicrun G2 combo's, that include the 10BL120, and a 4000KV 3652, and, even with a gyro, and 9 to12T pinions, not a single one of those trucks will go straight most of the time.
can't say much about MOTOR shaft length as I've never really had a problem there.

Have you tried adjusting your esc to take out some of the torque? I haven't had a single instance where I wished I had a brushed motor over brushless. I also dont play with many 2wd platforms.
 
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Can you slide the motor through the mount with the pinion on? Or spin the pinion around?

I don't have one so I can't look at it but that would be what I would do.

I don't want to give bad advice but maybe open the endbell hole up a bit if you cannot fit it through so you can get the pinion through mounted on the motor.
 
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Motor shaft is too short? Is that the issue?
Yes. The pinions I have are 15MM long total, and 12MM from the end of the pinion to the center of the grub screw, and every motor I have, the shaft is between 11 and 12MM long, so, when the pinion does fit, the screw is right at the end of the shaft.
 
Ca t say much about shaft length as I've never really had a problem there.

Have you tried adjusting your esc to take out some of the torque? I haven't had a single instance where I wished I had a brushed motor over brushless. I also dont play with many 2wd platforms.
I have always had a better experience running my 2WD's brushed, but, a couple years ago, I was convinced to go brushless, because they run cooler (which, in my experience, not always, and I only run 2S), which means a brushless motor should last longer, but, brushless motors make my 2WD's harder to control, and, frankly, I don't see the point to spending all that money on brushless, only to run it at 50% all the time just so the trucks are controllable. I'm not big into doing donuts, or drifting, so, for me, brushed just works better. As for things like turning down the punch, that doesn't always work either, especially with the 10BL120. Even the 10BL60 has that issue.
 
The traxxas motors for the slash have a longer shaft than average. I got a titan 12t in the kyosho sandmaster that forces me to drill a hole or just leave the spur cover off.
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The traxxas motors for the slash have a longer shaft than average. I got a titan 12t in the kyosho sandmaster that forces me to drill a hole or just leave the spur cover off.View attachment 278987
Oh, I know. Problem with that, I burn up Traxxas motors literally weekly. Before I finally tossed them, I had 16 Titan 12T's in a box, all of them lasted, at most, a week, in 3 trucks. Brushed or brushless, I only ever seem to have any luck with HobbyWing stuff. The old Arrma 12T (before the 2018 bankruptcy) used to last quite awhile, but, the new one, not so much.
 
Oh, I know. Problem with that, I burn up Traxxas motors literally weekly. Before I finally tossed them, I had 16 Titan 12T's in a box, all of them lasted, at most, a week, in 3 trucks. Brushed or brushless, I only ever seem to have any luck with HobbyWing stuff. The old Arrma 12T (before the 2018 bankruptcy) used to last quite awhile, but, the new one, not so much.
The bl2s systems for the same truck seem to run good for a lot of people. Haven't heard too much about reliability issues.
 
The bl2s systems for the same truck seem to run good for a lot of people. Haven't heard too much about reliability issues.
I had a BL-2S that I tested in my HPI Blitz, and had that same issue of it doing nothing but donuts. The real issue comes down to preference. Whereas most people think drifting and donuts and burnouts are cool, I don't. I prefer my trucks to be controllable on any surface.
 
I finally found some pinions that are short, but man are they expensive. $11 each plus shipping.

EDIT: I also found some Axial ones that look short for $4 each, but can't find any specs on them.
 
I had a BL-2S that I tested in my HPI Blitz, and had that same issue of it doing nothing but donuts. The real issue comes down to preference. Whereas most people think drifting and donuts and burnouts are cool, I don't. I prefer my trucks to be controllable on any surface.
I have 2wd in many formats. Brushed and brushless. I do my donuts on purpose but don't have a problem driving any of them. With or without a locker spool .
 
I have 2wd in many formats. Brushed and brushless. I do my donuts on purpose but don't have a problem driving any of them. With or without a locker spool .
With mine, they do donuts anytime I try to turn, unless I let completely off the throttle way before I turn. Maybe it's just because I am way more used to brushed 2WD, because that's what I use to race, but, no matter how I set the ESC, or the throttle settings on the radio, unless I make it as slow as a brushed setup, I can't control it the way I like to, so, I figure, why bother with spending more than twice as much on brushless only to never really use it.
 
I know, find a way to go back in time to 2014 and buy a whole bunch of the original Arrma red mega ESC's and 12T motors, since those I never seem to burn up. The one in my 2013 V2 Fury is 9 years old, and still going (one of the few things that wasn't stolen when I got robbed a few years ago).
 
With mine, they do donuts anytime I try to turn, unless I let completely off the throttle way before I turn. Maybe it's just because I am way more used to brushed 2WD, because that's what I use to race, but, no matter how I set the ESC, or the throttle settings on the radio, unless I make it as slow as a brushed setup, I can't control it the way I like to, so, I figure, why bother with spending more than twice as much on brushless only to never really use it.
I'm a big fan of brushed motors. Certain vehicles I like the extra power. I have a kyosho outlaw rampage 2wd. It's running bl120, and a quickrun sensored 17.5t 540 with amazing handling and control. Also got an fms f100 2wd running a hobby fans bl esc and 4800kv 540 with no issues. Both I run 2s only. Suspension tuning and throttle control is more critical with 2wd. The sandmaster, rj speed oval mod, are both brushed. The tt02 is 4wd, but with a locker in the rear so it drives more like a 2wd, 13t brushed 540, geared for a top speed in the high 20s. Is awesome on pavement.
 
Short answer on standardization; because all chassis are different. Traxxas isn't going to change their chassis layout to accomodate a motor and transmission setup meant for a Losi, and vice versa.
 
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