gear reductions?

[gooba]

has anybody tried using an hpi or rc4wd reduction box that bolts between the motor and trans? it looks like there may be some clearance issues with the servos but I was wondering if lo pro servos might fix that issue?

[bigford]

I have the Rc4wd gru. Its LOUD. The servo isn't
The problem it make the motor/tranny long

[Bo Wallen]

I have HPI Reduction 7/1 and 27 T Pinjong ( Hard to fit bigger pinjong ) running in third gear Very Slow. Would work in Super Heavy Hauler or Sled Puller.

[Cossett]

If your planing on using lowprofile servos just be aware they are a few mm wider and longer than stock servos are no mater what rig you put then in,
When I fitted one in my euro chassis I had to shave the servo mounts to fit the steering in,
And my cabover Im building with panetary the steering servo mount is at the maximun length in the chassis and very tight fit....

[Mustang46555]

I've used a park flyer style rear reduction between the motor and gearbox with some success. It gives a 4:1 reduction depending on pinion, possibly more if you can find larger pinions. It is long which limits where you can use it. I've had good luck in a stock King Hauler cab. It gets close to the grill but clears. Rather than low profile servos, consider spacers under the front transmission mount. it will lift the motor up enough to clear a standard Futaba servo.

[gooba]

Thanks for the replies guys. Bo how do you like the HPI reduction? That's the one ive been looking at.

[Bo Wallen]

Originally Posted by gooba

Thanks for the replies guys. Bo how do you like the HPI reduction? That's the one ive been looking at.

Well i've got a slow truck for sure and strong. Torque is insane......two of the mounting tabs on the gear case did not make it....gone. And the mounting holes need some grinding to make the motor/reduction fit a giant pinjong 27 T
Other than that it seems to work fine and not to much noise. One other thing is when you turn down the RPM before the gearbox the Noise is less and i don't think the gearbox like high rpm's anyway......things inside got a lot of play.
Of all different thing i tested i like the following combo the best when it comes to all around drivability. Not super expensive stuff. like Veroma gearbox etc.
Tamiya Gearbox 3 speed.
9 or 10 toth pinjong Hardened steel from Robinson Racing. (smaller than 9 toth eating the plastic gear quicker)
Transfer Case 2-1 https://www.ebay.com/itm/TRACTOR-TRA...19.m1438.l2649
This setup will give good speed in third gear and slow speed in first gear good for backing up.
I also use chain saw grease super sticky (the grease for the roller bearing in the sword) That lube good and make things less noisy. Again i think the HPI looks good but have to much gearing........it's a crawler thing.