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hi everyone new to the forum i am building a bl 3.3 revo with a gmaxx single speed conversion and i have heard that the pin in the input can break. does anyone know what yoy can use in place of it? also do you have to turn the diffs over? thanks for the help dave

Welcome to RCM Dave! You won't have to flip the diffs with BL. A BL isn't like a brushed motor; they can spin either direction and it doesn't matter, simply reverse the direction of the motor via ESC (depending on which one) or by switching any two of the three wires. You probably won't have any problems with the input shaft, but if you do, I've heard of people using nails, drill bits, and even allen wrenches. Use your imagination basically...

It's not the same as the REVO tranny, but I broke a roll pin in my E-Maxx transmission. I cut a 1.5mm allen L wrench to fit through the hole and bent it a tad to make it stay in. Then just hammered it through, and it worked great until I had to get rid of my Maxx. I converted it to a single speed, but made another pin to include with the trans incase the next owner wanted th 2 speed back.

If you can't get the roll pin out, RC Car Action suggests heating the shaft/gear with the pin in your toaster (NOT microwave!!!) for a while, then pulling the pin out while it is hot. Use oven mitts!

Good luck,
Brijar!!!

i am using an e-maxx trans. i guess i didn't make that clear. i found that a no. 45 drill bit fits fairly tight.

I used a 2mm allen wrench and some jb weld when mine broke.

Greetings! you didnt say, but which BL motor/esc combo are you using? if its the HvMaxx then you will have to either flip the diffs, or mount tranny in back-to-front, since you cant switch the wires around or change the motor rotation direction via programming.

i was leaning towardsthe novak HV system but from what i have been reading i might not be satisfied with it down the road. what else would comparable or close in price to the novak? i am probly going to use lipo batts. at this time this just for bashing. thanks dave

For that price the old 8-9XL feigao & MM esc with a good ubec and 4s lipo would be much more powerful with the ability to go much faster and still run reasonable temps. It is pretty much the 1st BL setup most people run, and is a proven setup- the 9XL will run cooler on 4s, and if you get a better esc down the road, it will also be good on 5/6s with sensible gearing. The HvMaxx is limited to 4s/14cells maximum, and is much more fussy about gearing, especially in a heavier truck, but still does fine in a light truck (9lbs or so).

The rollpin will break. Its really weak. I first did the allen key trick, but it eventually sheared. I then used a drill bit that was slightly larger, can't remem what size (was a fractional tho) and had the best luck with that. For the drill bit, I drilled the hole out w/ it, then pushed it thru. I bent/flattened the ends a bit to keep it in place. Since this solid, round, hardened tool steel, I think this is the strongest option.

Also, the MM/XL is a great way to go, else I'd go a higher end setup, like a Neu w/ MGM or Quark ESC for a truely powerful and reliable (read cool running) setup. Or wait (possibly forever) for the new Monster Max to come out or one of the other newer systems.

just this last weekend I was at a race and a guy was running a hv6.5 in his gmaxx. The race was 7min long, it was 60F outside, and he was geared 12/70, and the thing thermalled at the 5min mark. Sucky. He said he's had to send it in 17 times in the last however many years since it first came out. IDK, not exactly a ringing endorsement. OTOH, I ran a MM/8XL at the RCMonster bash and was fine over the 10min mains temperature wise.

Surely most have better luck, but I've seen/heard enuf bad things about them I wouldn't be too excited to get one.

Actually, I should correct myself. I used a 2mm allen wrench, not a 1.5mm. Sorry, I sometimes forget the sizes: 1.5mm for setscrews, 2mm for the screws that connect the drive cup to the diff output, and 2.5mm for most of my other hex screws.

Brijar!!!

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i used a 5/64 allen wrench. i ground the sides a little and pressed it in. it was a tight fit. i also flattened the ends a little bit. dave