Motor shaft and pinion length gripe.

[biggman100]

I did a brushless swap in a Gorgon last night.
Same issues. The brushed 550 is 1/8" longer on pinion side compared to a Spectrum brushless 3660.

I flipped the pinion in both directions, would not fit.

I used a Boom Racing motor spacer (BRLC7032)
to shim the motor.
I still ended up needing to install an oring between the red gear and the small bearing on the end of the slipper shaft.

Between the 2, I got the clearance, Clarence.



Nothing hit, no binding or funny noises so far.

The differences between the 2 motors was so small but it took an extra hour or so to figure out how to adjust for it.

Annoying!!!

That's why, when you see people doing brushless upgrades to the Arrma 2WD's, they use the HobbyWing 3660 3700KV motor, because it's the perfect fit. I finally figured that, since this is literally the only truck I have had that issue with, I'm just gonna get an Arrma 12T and be done with it, unless the motor that @KnowAir mentioned (the one from the 22S RTR), that he offered is the Dynamite 12T, and I'll just use that one. Those motors are nearly indestructible. I had one in my brushed 22S SCT that I routinely buried in mud, ran in snow and water, and punished at a concrete skate park and it lasted well over a year. I did the same thing with my brushless 22S SCT, and the stock brushless motor in that lasted maybe 6 months, but I ran that truck hard on 3S. That's one of the trucks I wish they wouldn't have discontinued.

 

[KnowAir]

That's why, when you see people doing brushless upgrades to the Arrma 2WD's, they use the HobbyWing 3660 3700KV motor, because it's the perfect fit. I finally figured that, since this is literally the only truck I have had that issue with, I'm just gonna get an Arrma 12T and be done with it, unless the motor that @KnowAir mentioned (the one from the 22S RTR), that he offered is the Dynamite 12T, and I'll just use that one. Those motors are nearly indestructible. I had one in my brushed 22S SCT that I routinely buried in mud, ran in snow and water, and punished at a concrete skate park and it lasted well over a year. I did the same thing with my brushless 22S SCT, and the stock brushless motor in that lasted maybe 6 months, but I ran that truck hard on 3S. That's one of the trucks I wish they wouldn't have discontinued.

Here’s what I found. The TRX Titan has the longest shaft. I know you said they don’t last long but you’re welcome to have all of it if you want em. PM me your address.

 

[KnowAir]

They all worked when I pulled them.

 

[RustyUs]

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.

Yes, it would be nice if all pinion gear manufacturers listed detailed drawings and/or measurements for their products.

Just be glad you do not have to worry about pinion gear step diameter/shank diameter yet That's a whole next level of frustration

 

[RustyUs]

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.

Sorry. Unless I'm wanting to do 6-minute maximum runs and/or wanting to keep things to a super low budget build, you won't convince me to back to brushed motors again.

I'm not saying you think it, but some people think "going brushelss" automatically means gobs of power. Just like brushed motors, everyone can choose the brushless motor power they want for their RC platforms. No doubt about it, a 3652 4000kv motor in one of my 2wd 1/10 off-road RCs (running on medium compound tires on loose/loamy/low~medium traction dirt) would be a handful to control. I will, sometimes, turn down the throttle end point to calm things down. If I have to turn down the top end of a motor more than a certain percentage amount to enjoy it, it's probably time to rethink a new motor purchase.

Also, a person could consider a 2-pole brushless motor to calm things down on a lighter weight 2wd platform. Instead of a 'foot on the floor' 4000kv motor, maybe a 13.5T would fit the bill to make a undrivable RC.... drivable. Just a thought.

 

[biggman100]

Yes, it would be nice if all pinion gear manufacturers listed detailed drawings and/or measurements for their products.
View attachment 279107View attachment 279108

View attachment 279109

Just be glad you do not have to worry about pinion gear step diameter/shank diameter yet That's a whole next level of frustration

It's bad enough sometimes trying to figure out tooth count, pitch, and bore diameter, especially with some of the really cheap pinions. If they make it so you have to start matching step diameter, I'm done at that point. Luckily, the engineers and designers already figured all that out before I even got there.

 

[biggman100]

Sorry. Unless I'm wanting to do 6-minute maximum runs and/or wanting to keep things to a super low budget build, you won't convince me to back to brushed motors again.

I'm not saying you think it, but some people think "going brushelss" automatically means gobs of power. Just like brushed motors, everyone can choose the brushless motor power they want for their RC platforms. No doubt about it, a 3652 4000kv motor in one of my 2wd 1/10 off-road RCs (running on medium compound tires on loose/loamy/low~medium traction dirt) would be a handful to control. I will, sometimes, turn down the throttle end point to calm things down. If I have to turn down the top end of a motor more than a certain percentage amount to enjoy it, it's probably time to rethink a new motor purchase.

Also, a person could consider a 2-pole brushless motor to calm things down on a lighter weight 2wd platform. Instead of a 'foot on the floor' 4000kv motor, maybe a 13.5T would fit the bill to make a undrivable RC.... drivable. Just a thought.

It might just be me, but, with brushless motors on a 2WD, I can never seem to really control them. About 4 years ago, when I bought my first brushless set up, I used an original V2 Arrma Fury (there are several posts on here about everything I tried to make that truck do what I wanted, and never could), and a Racers Edge Pro2 as test mules, and tried different motors, different KV's and different can size, different pinion sizes, and, the trucks were either way too fast and hard to control, or slower than they were when they were brushed, and it's never changed. They are either too fast, or snails pace slow. I can never find a happy in between. The only 2 2WD's I could ever control brushless, that weren't too slow, or too fast, were a Traxxas Slash that I bought used, and a Losi 22S SCT RTR that i bought new that came brushless. Even matching my trucks to the specs the 22S used (60A ESC and 3300KV 3650 (that whole experiment actually turned into a rather big argument on here, because people were convinced I just had to have a 120A ESC)), I still can't get any of my other trucks to really handle on a brushless set up. Running strictly 2S, I have had brushed trucks that were just as fast as that 22S was, and, in a couple instances, even a bit faster, so, after constant frustration with brushless and 2WD, I think I'm just gonna stick with brushed for them and brushless for the 4WD's

 

[CertifiedMike]

Yes, it would be nice if all pinion gear manufacturers listed detailed drawings and/or measurements for their products.
View attachment 279107View attachment 279108

View attachment 279109

Just be glad you do not have to worry about pinion gear step diameter/shank diameter yet That's a whole next level of frustration

Adjusting 'E' ever so slightly could have fixed my fitment issues with ease.

The pinion and spur were colliding, not meshing. Slightly deeper cut teeth 'E' into the 'step' area ’C' and the gears would have meshed fine. I would have been set.

I suppose a slightly thinner spur could have also worked.

Sorry. Unless I'm wanting to do 6-minute maximum runs and/or wanting to keep things to a super low budget build, you won't convince me to back to brushed motors again.

I'm not saying you think it, but some people think "going brushelss" automatically means gobs of power. Just like brushed motors, everyone can choose the brushless motor power they want for their RC platforms. No doubt about it, a 3652 4000kv motor in one of my 2wd 1/10 off-road RCs (running on medium compound tires on loose/loamy/low~medium traction dirt) would be a handful to control. I will, sometimes, turn down the throttle end point to calm things down. If I have to turn down the top end of a motor more than a certain percentage amount to enjoy it, it's probably time to rethink a new motor purchase.

Also, a person could consider a 2-pole brushless motor to calm things down on a lighter weight 2wd platform. Instead of a 'foot on the floor' 4000kv motor, maybe a 13.5T would fit the bill to make a undrivable RC.... drivable. Just a thought.

I don't think brushed motors are slower, just less efficient. They build more heat. Require more maintenance.

I have a couple vintage Team Checkpoint motors that could bend time. Gobs of power!

We have lipos now for more power and less weight and heat loss compared with similar nimh packs. I think this is HUGE!

We also have micro fans to help with heat now.

I intend to build one of these Optima Mids to be a brushed, retro track car with vintage components but use lipos and fans too.

Maybe just restore my original car even.


I always thought nimh batteries were 'the weakest link' when I used to race.

I'm pretty sure even the little 2200mah lipos have more power than a Tamiya 6cell stick pack did 40 years ago.

I don't expect to get long run times but I bet the brushed car will run great on a carpet track.

It only needs to run long enough to win the race.

The Gorgon I just put together has a 3900kv/120a spektrum combo in it.
I don't have a fan on the motor yet so testing was brief.

It is insanely fast on 3s!

So far I have been able to keep it driving straight as long as I can keep the front wheels down. This is on asphalt tho.

I am REALLY looking forward to putting the truck in some dirt!!! I am thinking I'll need to dial it back a bit or I will also be doing lots of donuts.