Mechanical Brakes

the speed calc. says around 40 mph on 4s which is what i run my 9xl on, i will just run it till i thermal or ruin the motor

thanks for the suggestions, do you think that i should consider a 1700kv motor and keep the gearing the same? would the temps be ok?

so a 1515 2.5d /s would be a good option? the speed calc. says it would be 39mph


i think it felt much better with this braking and i was only running on asphalt

[jhautz]

Yea kv wise the 1515/2.5d would be good, but its a bigger diameter so it forces you to use a bigger spur. I would look at going for a 36mm can motor. Feigao, Hacker, Lehner, etc....

are the 1512 series the same diameter?

the 3d/s would be an option if it has a smaller diameter, but for some reason i think the neus are the same diameter but are diff. lengths

[jhautz]

Yea. All the Neu 15xx motors are the same diameter. The finned cans are even bigger.

I think the Neu smooth cans are about 40mm. That 2 teeth on your pinion you would be giving up with the extra 4mm motor diameter vs a 36mm can motor.

[Shark413]

Regarding the pinion clearence, one of the biggest issues using mechanical brakes is that because of the motor can hitting the disc there is a limit on how small you can go on the pinion. I solved this by spacing the motor back a few milimeters so that it clears the disc and therefore I can run very small pinions (10, 11, 12, 13T). Since I am running the Kyosho 46T spur and a hot running Feigao I need to run a 12 or 13T pinion. This also eliminates clogging. On the downside, this setup puts the pinion on the very end of the motor shaft. Because of this I built up the motor mount/chassis to be extra stiff (no flex). So far I have had zero issues with this setup.


This is a 13T pinion.


These pictures show the test fitting and the rough parts (motor mount).

[jhautz]

Looks good shark. That is the solution I was trying to describe a couple posts ago.

Last night I sketched up a spacer plate for the front of a motor that would allow for the brake disk clearance and just sent it to Mike to see if he could machine one up for me. It should allow the use of an almost full range of pinion gears. At least down to 12T by my calculations. It should be able to bolt up to just about any motor using a normal bolt pattern and with any of the RCM style motor moounts allow clearance for brake disks. Like you said though shark, it will put the pinion farther out on the shaft, but I have been running a really long Tekno clutch assembly in one of my buggies which effectivly almost doubles the shaft length where the pinion gear is and havent had any issues so I would think this should be fine too.

Heres the sketch of what I'm thinking.