The Twin Force is a monster right out of the box - with it's lightweight frame (it's lighter than a TXT even loaded with 2 batteries and larger motors!) and powerful 14.4v driveline, it'll pull wheelies from a standstill and hold them for a block or two! My truck is powered by 12x 2400mah cells and a Mtroniks3 Super E-Truck ESC. Although I've had my eye on the Twin Force for a while, I've didn't buy it earlier because I never liked the EVX esc as they've burnt out twice on me for no particular reason. When I discovered this alternative I gave it a try and must say it's a great performer.

Body Pics

Not the final body for sure. Some of you might recognize this from my TXT racer project. The TXT has since been sold but the body shell remains - and now aptly graces the new race rig. The custom chassis that I made allows the use of all bodies drilled to fix TXT/Maxx trucks without modifications. Although the stock Twin Force shell doesn't look bad, it just hasn't grown on me. I've got a hummer shell with a paint scheme in mind when time allows.

Steering And Driveline mods

In the first pic you can see the steering modification on my truck. The stock steering works great actually but with so many links (5 link-rods!) it quickly develops significant play. I opted for a custom servo mount anchored firmly to the suspension arms. The servo now drives the wheels directly for a simple yet efficient steering setup. It took a long time to figure out how to make everything fit though, as there is not much space there to work with!

The middle pic shows the front universal. The Madforce had an irritating problem of the center dogbones ejecting off hard landings because the swingarms would flex and "spit" the dogbones out. The Twin Force doesn't have this problem because Kyosho included longer drive cups to secure the bones - the longer drivecups however, would "eat" into the dogbones when the suspension flexed. Universals should solve this problem while contributing to a more efficient backlash-free drivetrain. Although I fitted a Kyosho aftermarket part in the rear, the LHS didn't have any more for the front, so I bought an OFNA part and milled it to fit the front. The OFNA universal actually works more like a CVD with a ball machined at the joint so it should work very well.

Both front and rear diffs have also been opened to install an additional 2 diff gears ber differential. This makes them more bullet proof. For guys looking to do this, you'd be interested to know that in addition to the Kyosho parts for this mod, you can also use Savage or Hyper7 diffs as well. The diffs were then packed with 100,000wt and 50,000wt oil in the front and rear respectively and sealed.

The stock setup of the truck also includes a one-way bearing in the front of the truck. This makes for very effective cornering but the downside is poorer braking and reverse. I eliminated the front one-way by filing a flat spot on the center sprocket shaft and using the longer drive cup from the axle to replace the one-way bearing and stock cup. Braking is now so strong that the truck will flip when braking hard on tarmac. The downside is now that I've lost some steering. I'll have to do further testing to see which setup I prefer.

Click on the pics for more information about the mods.

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Other Custom Mods

The entire driveline sits on a custom chassis that I designed and milled out or 3mm 6061-grade aluminum. The chassis allows several suspension and ride-height tuning options and also allows 3 different mounting positions for the battery trays to tune CG. The chassis design also allows full suspension travel even when lowering the truck.

In the third and fourth pics you can see how the chassis looks without the stock battery trays attached to the sides - it looks a lot cleaner and is definitely lighter. I designed a location for a single battery pack to be fitted up front should I decide to convert to a single battery setup in the future. The location keeps the weight close to the center of the chassis while balancing the weight of the motors to keep the front end better planted.

One other option I included into the design was the ability to still use the stock steering setup if I decided to. Although the axle mounted servo performs well, I can still re-locate the servo up to the chassis if I decided to go mudbogging, etc.

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Performance
I haven't had a lot of time to run the truck with the mods yet but in the few test runs everything seems to perform well. The steering has suffered with the removal of the one-way bearing but I suspect some diff tuning will help. The truck feels very planted offroad and jumps well too - when time allows I will be doing some head-to-head testing with my friend's stock Twin Force as well as trying some bigger jumps to see how the truck performs.

Hope you've enjoyed the write-up! Click here to see continue reading about this project, including my new body shell as well as some action shots from a recent bash session!

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