Jammin CRT .5 Project

[riceman]

Well I've been riding the coat tail of BrianG's thread so I guess it's time to post my own. Here is what I have so far:

1. Like BrianG I'm experimenting with the 46t Kyosho Nylon spur. In doing so I did a couple of mods needed to do to accommodate the thicker gear. The main thing was using an LST2 axle outdrive cup. As BrianG documented the stock bearing is an odd sized 15mm od. With the Kyosho a more common 8 x 16 bearing can be used but the diff mount must be bored out 1mm to accommodate it. Everything else fit well after using 3 gaskets to get the ring and pinion mesh to turn without binding. The new center diff setup is now about 1.5 mm longer than stock so I elongated the chassis mounting holes to accommodate.

2. Now that the rear diff cup of the center diff is for an 8mm ball size dogbone I needed to match the rear and find a dogbone that would fit. Luckily I had both parts in hand. The rear diff cup is from an MGT differential and the 3” long 1/8th scale dogbone is from an HPI Savage. I ended up using two 8 x 5 bushings to fit the 1/8th scale diff cup on the 5mm CRT mini shaft. One of the bushings is slotted to allow the set screw to go through it and hit the pinion shaft. I’ll see if I can post some more detailed pics later.

3. The motor is a Mamba Max 4600 I robbed from my T4. The pinion is a 15t 5mm bore that I sleeved with a copper bushing. I drilled out the bushing to still allow the set screw to hit the motor shaft.

Some pictures:
Motor mount is rather crude right now. I'll clean it up a bit later. Not nearly the nice craftmanship as BrianG's!


Diff cup for rear differential and 8 x 5 mm bushing


Nice fit with the 3" HPI 1/8th scale dogbone. You can see the green fuel tubing I used in the CD diff cup to keep the dogbone deep in the rear diff cup. There is actually plety of room to work with with those 1/8th cups.


I had to Dremmel the front chassis brace a bit to make room for the center diff moving forward 1-2mm.


Bench test setup with 6 cell NiMH pack


Now it’s a matter of putting the rest of the truck together and getting the battery mounted and then on to some real world testing. For now here is a vid of the first bench test.

http://www.youtube.com/watch?v=JBzp7tUBjt8