E-Revo with Twin Force Tranny

[Lonewolf039]

Well, I blew up a diff in my twin force, so I decided to convert my Revo to brushless while I was waiting for parts. It took around 2-3 hours, and is not real pretty, as I was just seeing if it would work. It worked great, although I am pushing the slipper to the max. The hottest part of truck after a run is the slipper, at around 150. Everything else is cold, as it should be after playing in the snow.




I am running the ESC in the Twin Force electrical box, and the temps are usually around 100-120 after a good run.


The battery packs are just zip tied on, I was in a hurry to get it going.

Stock Revo front drive shaft. Long axle shaft in the rear.

[Lonewolf039]

Tucks up real nice.

I had to space the motor plate up 3/8 inch to get the outputs in the right place. I used some delrin I had kicking around.


Motor plate and chain drive.

I am using Revo shafts on my Twin, so the outputs bolted right up.

I enlarged the front part of the frame 1/8 inch on each side to fit the tranny.

The tranny out of the truck. You can see the delrin blocks that everything bolts to.



Overall, I am quit happy with it. It is a little slower than a stock Revo, but a better motor will fix that in a hurry. With the two NiMH packs, all up weight is 10.5 pounds, so a good Lipo pack will also bring that down.

[t-maxxracer32]

so what are the advantages of doing this?

it looks pretty cool and differnt though

[Lonewolf039]

No advantage, the main thing was I had all the parts laying there, and wanted to see if it would work. The Twin Force tranny is quite beefy and simple, it just needs a better slipper.

[lincpimp]

Looks like a revo slipper could be installed in place of the stock slipper. That should be able to hold up to the power. Is the shaft 5mm in diameter?

Originally Posted by t-maxxracer32

so what are the advantages of doing this?

it looks pretty cool and differnt though

The advantage??????? No gears, no second speed, no one way bearing.... just a slipper and a chain So for me, this system should be wayyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy more solid than the stock revo trany.

I'll gine a chance to my stock revo trany, and if i break it, i put this twin force setup in mine!!!!!!!!!

Oupsss! could you tell me if the twin force slipper gear is 32 pitch or MOD1???
Look like to be 32 pitch

[Lonewolf039]

Originally Posted by david lamontagn

Oupsss! could you tell me if the twin force slipper gear is 32 pitch or MOD1???
Look like to be 32 pitch

Ya, it's 32 pitch, but if converted to a revo slipper, you could use the mod 1 revo gears. If not the revo slipper, you could use an MGT spur gear with the stock slipper, they are mod 1. You just have to slightly ream out the center to fit the stock 10x6 mm bushing.

lincpimp
Looks like a revo slipper could be installed in place of the stock slipper. That should be able to hold up to the power. Is the shaft 5mm in diameter?

The shaft is 6 mm, but could be machined down to 5 mm. The main problem is that the revo slipper would move the gear further away from the motor. The chain sprocket already takes up a fair bit of room. Look at this pic, you can see it between the motor and slipper. The revo slipper will take up some room too.


I have been looking hard at it tho. I really want to get a decent slipper for the Twin.

[suicideneil]

Is it just me, or is this the most compact and tidy layout you've ever seen. That electronics box is perfect, and makes everything so tidy. The tranny is perfectly place low down on the center-line of the chassis, yet doesnt hang out the bottom at all. As for battery trays, I would suggest some like Serum's. Its a shame the slipper is a bit week, but Im sure a fix can be invented for that; other than that its a brilliant piece of conversion work, well done!

[Lonewolf039]

Originally Posted by suicideneil

Is it just me, or is this the most compact and tidy layout you've ever seen. That electronics box is perfect, and makes everything so tidy. The tranny is perfectly place low down on the center-line of the chassis, yet doesnt hang out the bottom at all. As for battery trays, I would suggest some like Serum's. Its a shame the slipper is a bit week, but Im sure a fix can be invented for that; other than that its a brilliant piece of conversion work, well done!

Thanks, I like how it turned out. It is very compact. Serum's conversion was one of the ones I really like, and I was going to do the battery trays the same way, but now I am thinking of chopping up the stock chassis and tigging or bolting on some aluminum battery trays.

Well, I fixed the slipper. It all boils down to the fact that I was using a GT2 spur gear, and the slipper pads for the GT2 are pretty slippery. I tried a couple of different materials, and none seemed much better. I went back to the stock Kyosho spur gear and now the slipper is pretty much locked up. I had to back the tension off a fair bit to get any slip. So the moral of the story is that you need the right material for a monster truck slipper pad. Now if I could just find some pad material the same as the Kyosho stuff, I can use the GT2 spurs, as they are really easy to get.

Also it looks like I might be able to use Savage X spur gears, once I get some Mod 1 pinions and a decent motor.

[crazyjr]

thats a nice conversion, as said very compact. I thought there was a one way on the front of the TF

[Lonewolf039]

Originally Posted by crazyjr

thats a nice conversion, as said very compact. I thought there was a one way on the front of the TF

The one way is built into the dogbone cup, so when I converted my twin to the revo shafts, I got rid of it.

I played around with a few gears and the Savage X spur will work, it's just a little big. I had a 49 tooth kicking around. A 46 tooth would work perfect.

[Lonewolf039]

Ok, I've got the slipper issue fixed, but now I think I have figured out why the performance is lacking. I ran my whattmeter for a run today, and my ib4200 batteries are way down in performance. When they were new 2 weeks ago, I was getting 72 amp peaks with a voltage of 6.26 volts per pack. Now i just got peaks of 54 amps, and the voltage dips down to 5.6 volts. Total mah was only 3400 until they dumped. They have been taking 4200-4300 mah on charge, so I thought they were doing good, but now I realize they are getting really weak already. I only have 25-30 cycles on these packs. I have a lot of small lipo packs for my 3d planes with over 100 cycles on them with very little performance drop. I got the nimh batts for winter bashing, thinking they would be more durable then lipo in the snow, but I guess I wasted $90 on them. I wonder if taking apart the stick packs and balancing them would help? Anyone know much about these ib4200 cells?

[lutach]

Originally Posted by Lonewolf039

The one way is built into the dogbone cup, so when I converted my twin to the revo shafts, I got rid of it.

I played around with a few gears and the Savage X spur will work, it's just a little big. I had a 49 tooth kicking around. A 46 tooth would work perfect.

I have that same spur in my MBX5T. I also have the steel 48T one. They all work very nice.

I've try to find Twin force parts on the web, but..............NOTHING.
Tower, A Main, flebay, nothing
I would like to have this twin force chain drive system, but as i can see, any hobby shop have the twin force parts in stock.