Brushless Kyosho S-RR

[Shark413]

Ok, after taking everything apart I was going to make a new brace but after checking the flex I notice the center diff supports were a little loose. I am using a 49T spur so I had to raise it to clear the chassis. Kyosho supplies some plastic spacers for this purpose, but they were not designed to support the diff and a brushless motor. The plastic is too soft, and gives, which adds to the flex. Mike's mount is a great piece of engineering and many have used it without issue. So I decided to stick with Mike's mount as is, I will machine some new diff spacers out of 7075 aluminum which should help with the center diff flex. Most of the force from driving a off-road truck is up-and-down, not side-to-side, so I think the mount will be fiine once I make new spacers.

[Shark413]

Well no more machining for a while, my bad machining skills blew the gear box in my mini mill. But I was able to finish the spacers the old fashion way, saw, dremel and files.


Broken gear - Mini Mill


Carbon Fiber spacer for front diff support


Aluminum spacer for diff/motor mount.

[cornolio]

hi shark413,im the guy who got your old cen conversion.im having so much fun with it with the MMM.only problem is i keep stripping spur gears.i stripped 3 already and and im not even doing any jumping.i got a steel spur gear but im reluctant to try it coz i might melt my pinions or something else.can u give any advice?id appreciate it.thanks

[Shark413]

cornolio, glad to hear from you. I also had issues with stripping the plastic Kyosho spur gears, so I swithced to steel spur and a hardened pinion. I have been running these on all my brushless conversions with no problems. The important thing is you must use a Mod 1 hardened pinion, which RC-Monster, Impaktrc, MegaUSA all sell. I am also using a wide Robinson Racing Losi spur gear that is wider than normal and spreads the contact area out more, which improves wear on the spur and pinion as well.


http://www.amainhobbies.com/product_...ducts_id/12711
Spur comes in 47, 48 and 49T.

[cornolio]

thanks shark.sorry for hijacking your thread

[Shark413]

cornolio, no problem. Just to clarify, if you switch to a steel spur the hardened pinion is a must. The wide Robinson Racing steel spur is optional and a nice to have but not a requirement.

[Shark413]

Ok, got the mud guards and installed them.

[Shark413]

Updated photo.

[cornolio]

another question.what oil weight do you use for your center diff?thanks

[Shark413]

cornolio, I am currently running what Kyosho recommends, 7000 wt in the center diff, 5000 in front and 2000 in the rear. I find these are good starting points for my set-up.

[Shark413]

Ok, I finally was able to get (bribe) my nephews to come out to the track and shoot some video of my brushless ST-RR in action. Still need to fine tune the shocks and brakes.

http://www.youtube.com/watch?v=GC9rYX8hLPk
Updated with a better quality video