Another Brushless REVO conversion - RC-Monster Forums

12.23.2006, 01:47 AM

ive got the 36t spur on a 16t pinion, and after about 20mins of speed runs and off roading it, the esc is warmish to the touch .

Shark413 · 05:49 AM

Ok, I decided to work on the body and I discovered that the body wouldn't clear the ESC when mounted in the back. So I decided to move the ESC to the right side of the tranny. Body now fits, ESC proctected. Originally I wanted the CG centered left to right and slightly bias toward the rear. With the batteries mounted side saddle there is more weight on the left side (battery plus motor on left, battery, ESC, receiver on right). But, mounted side saddle the batteries are very low which lowers the CG, and theroetically should make it corner better. I decided to experiment and I mounted a carbon fiber plate on top of the rear shocks, using some alloy brackets and the rear body mount. On this I added the left side battery, so I had a battery on top and one on the right side. In this configuration the CG was almost perfectly balanced left to right with a rear bias, just what I wanted. But with one battery mounted on top this moved the CG higher. The top configuration I assume would be similar to a Revo conversion using the E-Maxx tranny with the motor mounted on top. The utimate test I guess would be to try both configurations on the track and see which works out better. I appreciate your feedback and suggestions.

Body trimmed and mounted.

ESC moved.

CF top plate mounted.

Pack mounted on top.

Side view.

Happy Holidays.

Shark413 · **Gearing -** 12.23.2006, 05:59 AM

Regarding the gearing, I have a problem. Using the special motor mount I can only use the 40T spur and 15T pinion. I cannot move the mount any further to the right to adjust for smaller Spurs or pinions. This is because I am using the Revo Mod 1 gears. The mount was originally designed to use the stock 48pitch gears off an E-Maxx. I like the Mod 1's because they are stronger. I guess I could drill and re-tap some new holes to allow me more adjustment, but there isn't much selection in Mod 1 pinions with a 3mm bore hole and the largest spur traxxas makes for the Revo is a 40. I could probably mod a truggy spur to fit, but that would be more work. And on the track I race on, 36 mph top speed and super strong accelleration works out perfectly.

Shark413 · 06:09 AM

Serum, It's just that with a battery and motor on one side and a single battery on the other the CG is heavily bias to the side with the battery and motor. I am worried that the handling will be adversly impacted. The track where I race has several double and triple jumps and the thought of a left side heavy 10.5 pound MT hitting those jumps at speed could be trouble. I imagine it would start pulling left after each jump. I agree that with the batteries sitting so far back and high that it seems like it probably won't handle very well. But Like I said, It will be easy for me to move the batteries around to see how the different battery configurations effect the handling. I won't be able to run it in the dirt for a while (Holidays). Thanks for the feedback.

BrianG · 12.23.2006, 08:35 PM

Quote:

Originally Posted by Shark413

Regarding the gearing, I have a problem. Using the special motor mount I can only use the 40T spur and 15T pinion. I cannot move the mount any further to the right to adjust for smaller Spurs or pinions. This is because I am using the Revo Mod 1 gears. The mount was originally designed to use the stock 48pitch gears off an E-Maxx. I like the Mod 1's because they are stronger. I guess I could drill and re-tap some new holes to allow me more adjustment, but there isn't much selection in Mod 1 pinions with a 3mm bore hole and the largest spur traxxas makes for the Revo is a 40. I could probably mod a truggy spur to fit, but that would be more work. And on the track I race on, 36 mph top speed and super strong accelleration works out perfectly.

Maybe "machine" out the mesh slots on the mount for more range??

BTW: The person who made your mount actually uses 32p gears IIRC. Maybe see if the Jato 54T spur fits there? It might not since it is kinda large in diameter compared to the Mod1 40T, but might fit since you have the spur spacer...

Shark413 · 12.24.2006, 03:35 AM

BrianG, as you may already know the 40T mod 1 spur comes very close to the chassis. There really isn't much room for a larger Mod 1 spur gear. With a 48P spur you can probably squeeze in a slightly bigger (numerically more teeth) gear because they are physicaly smaller. I may go that route eventually, if track testing shows I need the gear (lower) change. The slots on the mount are pretty much as close to the edges as you could make them. As I said you would have to drill and tap new screw holes to be able to use smaller Mod 1 pinion/spur gears. The accelleration is fine, I was just a little worried about the top speed, which would require a smaller spur/pinion. I need to radar my nitro Revo to see how they compare, I don't trust the Traxxas advertisments (40+ mph). Also, I don't think the gear box was shifting into 2nd gear. So I need to adjust the transmission shift point to make it shift sooner, to see if this makes a differnce. Overall I am very happy with the conversion, because with one as complicated as this it normally takes several prototypes to get it perfect. And there is a lot of fine tuning that still needs to be done (gearing, close ratio gears, shifting adjustment, more powerful batteries, different tires, battery placement, CG adjustments, etc.). This will require track time and that will have to wait until the new year..

Regards

BrianG · 12.24.2006, 02:32 PM

Yeah, I knew the spur gets pretty close, but wasn't sure if that spur spacer piece you got as part of the conversion kit added enough space to allow a little more clearance for larger spurs.

Since you're still using the two-speed tranny, you could gear up by simply getting a larger pinion. The thing is, to get the pinion to physically reach the spur with that mount, the pinion will probably need to be big.

Don't forget, there are three 2nd gear options, close, normal, and wide ratios, which you can use to get the gearing you want.

Shark413 · 12.24.2006, 06:36 PM

BrianG, yeah I have the close ratio gear set. So I have several setups to test out. Std gearing and close ratrio internally, I have a 36, 38 and 40T mod 1 spurs, I have a 13 and 15T mod 1 pinions and I could use the adpater and use 48P Spurs and pinions. But I really like the mod 1 gears. I also want to get the wide ratio gear set as well. How is your brushless Revo working out? Have you tried Lipo's yet?