B4 Transmission in Gold Pan

[ck33]

Been reading RC10Talk for over a year - Glad to finally share some information! Saw a recent post on this topic and thought this is the perfect time to start posting.

Like many of the folks on this page, I used to race my RC10 in the 90's and am now back running my cars with my son! My 90's race car was piecemealed up with all the typical hop ups, and I fortunately never threw anything away. Fast forward to 2012, in the intrest of getting a 2nd car going to run with the kids, I found enough parts to get a second runner together. Had most of the parts, and bought a few, but one problem: No rear bulkhead or transmission!

Below is a build of my gold pan with homemade rear bulkhead, and B4/SC10 transmission. The B4 transmsissions are much cheaper and easier to find, and the bulkhead wasn't too bad to fabricate!

The core of the installation is a carbon plate that the trans is mounted to. I cut out the square hole in the carbon plate, and mounting screw holes for the rear of the trans. Added more holes to clamp the plate between the chassis and rear arm mounts. This also accomodates the slight height difference of the outdrives between the stealth and B4 trans.

View of the entire rear end. B4 wing mouns; homemade shock tower and rear bulkhead

View of attachment method of trans to gold pan. Trans is screwed to carbon plate. Carbon plate is held down by rear arm mounts. NO HOLES IN GOLD PAN!

Top view - axial layout of bulkhead. Bulkhead was made from 3/8 nylon strip. Shock tower ended up on back for proper alignment with rear arms. I think I will mill the next rev. RC8 Body Mount

2nd view of trans attachment to bulkhead. Top shocktower screws are slightly widened to accomodate trans mount screws

Need a shot of the whole car!

View of the wing mount - Not very happy with B4 mounts. From suggestions from this board, going to look for RB5 mounts as they look like they have two screws

[jwscab]

Nice Job!

Kyosho RB5 wing mounts, or also, Losi xx4(or xxx4?) can't remember which, might be both actually. comes with a few body posts too....

[Lonestar]

Interesting

what brand of motor is this? Interesting head...

Paul

[ck33]

Motor is 17T Double Venom. Available at Tower Hobbies. I think it is one of the few brushed motors they still sell...

Heat sink looks cool, but terrible for alignment and brush fit.

[rc10wishlist]

what are bulkheads,im new to rc cars

[rc10wishlist]

i only ask because im thinking of switching to the b4 tranny

[scr8p]

it's what the shock tower and tie rods mount to.

[ck33]

As sc8p mentions, bulkhead is where everthing attaches. It's the black piece with the rough edges The rear bulkhead is significant in this case for two reasons:

1. No longer available from AE or aftermarket
2. A modified/machined stock rear bulkhead probably wouldn't line up with the holes required for the front of the B4 trans.

As mentioned in the original post, the rear bulkhead wasn't too bad to make. I purchased nylon from McMaster-Carr, then cut it out with a wood band saw.

Only catch (you can see it in the pictures - top view), is the 3/8" nylon does not quite reach the chassis screw location. I tried to bridge it with an additional plate, but it didn't work. Next rev will either start with thicker nylon, then mill down. Or, start thinner with thick interface blocks (trans and front chassis screws).

[littleVETTE]

very cool. how's the buggy running?

[ck33]

Buggy runs pretty solid. With a 17TD motor and cheapie ESC, it is a dog compared to my other RC10 (graphite/10.5T brushless). Just using it for bashing around the house, and occasional trips to an outdoor 1/8th scale track.

I'm amazed at the difference between the graphite and the gold pan. Graphite is way more responsive, with lot's more turn-in. Seems to make sense as the pan has lots more roll inertia, but the difference seems too big for it to be the complete explanation. Pretty sure both cars are set-up the same, but probably need to dig a little further into shock positions, caster blocks, etc. Bulkhead link positions were directly transferred from the stock bulkhead.

No problems with the trans. B4 is much quieter than classic 2.25 stealth (even with recently replaced geartrain). B4 slipper is much improved.

BTW - Great suggestion from above on the xx4 wing mounts. Parts look like a great fit. With only one screw at each mount, the B4 mounts keep spinning around and loosening.

[Claymore5150]

I'm surprised that yours is louder than a B4?
My rig is one of the most quiet on the track with 2.25 stealth/b4 topshaft V2 slipper.

I'm running boca bearings throughout, nothing special. The only real difference is I run the ceramic balls in the diff (but not on the thrust).

I DID notice that mine became noticeably more quiet when I switched from using a robinson pinion to...get this....
a TRAXXAS pinion. The mesh I get with the TRX pinion and robinson spur is amazing and soooo quiet.

Worth $2.50 to try it out...see if it helps.

[Claymore5150]

Oops...meant Kimbrough, not Robinson when I was referring to the spur....my bad.

[reptilejason]

were you able to run that motor with the RC10's stock gears, transmission, etc?

[ck33]

Thanks for the tip on gears - I agree Kimborough are tough to get quiet. I think I'm running a Robinson now that's aging a bit. I have the old style nylon RPM gear cover too that might radiate a bit more noise. That's why these cars are so much fun; always something to tinker/experiment with!

No problems with 17T Double in conventional/stock configuration. I ran this motor with a stealth 2.25 gearbox, 81 T spur, and 19 T or 20 T pinon in my other car. I think Tower also has the same brand (Venom) motor in a 19T and 15T. Lots of people race "Spec" class with 19T motors against comparable brushless motors.