CC-01 durability

[emory70]

Looks like I'll be using a long wheelbase CC-01 for my winter buildoff ride. A major consideration is power. I'll be converting it to rwd only, and I need to overpower it a pretty decent amount. I'm not talking 6s or anything, but I do want to go brushless, and it's gotta be fast.

How hard can I push a CC-01 before I destroy it?

[mongoose1983]

Nice project. I'd say the chassis is remarkably resistant in stock fashion. If you use bearings and lube correctly the differentials it will go alright for a very long time. If you want it to be fast I'd say the thing you should care about is the body, actually. Good luck with the winter project!

[ChrisRx718]

Rear diff housing can be a pain.

The diff itself has a habit of coming apart during use, as it's a big metal unit held together with 3 tiny screws. Decide whether you're locking the diff or not (leaving it un-locked will make rwd much easier to drive) and then I recommend thread-locking those 3 screws. Then the plastic diff casing itself is pretty strong, provided you don't strip the threads holding it together. If you do (I recently refurbished an old model from eBay) then you can drill these through and use a longer screw + nylock nut instead.

Another point where people have highlighted a similar 'mod' is the gear cover itself which locks the motor mount and spur together. If you over-tighten this screw you end up in a similar predicament, but again the chassis can be drilled and a screw / nylock nut combination will solve it - although I've never managed to have a problem with this part.

Look forward to seeing your build. I'm thinking of using a CC01 for the basis of my winter build too, albeit in a pretty stock condition.

[derv_scaler]

As Reillour says you can through bolt the gear casing and rear axle to toughen it up, but what will kill a transmission is torque rather than outright RPM so I reckon you'd be OK. If you find yourself killing axles/axle casings you can get some extremely tough axles from RC4WD.com.

I have to disagree about an open diff being easier to drive than a locked though, with an open diff you'll get bags of wheelspin, but only on one wheel and it'll break traction and you'll lose momentum, with a locked diff things are much more predictable, both wheels will spin at the same rate and you'll be able to balance the car on the throttle. One of my 1:1 vehicles has a limited slip diff in the rear axle and it's a joy to drive hard and is very controllable (on a private course, of course officer )

[XV Pilot]

The top gear cover is a known issue, fine if the vehicle is run in stock form, but prone to lifting if power is upgraded. This can pull the screws out of the chassis tub.

A solution is to use longer screws in the initial build. I used 12mm ones on my CC01, and have had no issues so far.

[ChrisRx718]

As Reillour says you can through bolt the gear casing and rear axle to toughen it up, but what will kill a transmission is torque rather than outright RPM so I reckon you'd be OK. If you find yourself killing axles/axle casings you can get some extremely tough axles from RC4WD.com.

I have to disagree about an open diff being easier to drive than a locked though, with an open diff you'll get bags of wheelspin, but only on one wheel and it'll break traction and you'll lose momentum, with a locked diff things are much more predictable, both wheels will spin at the same rate and you'll be able to balance the car on the throttle. One of my 1:1 vehicles has a limited slip diff in the rear axle and it's a joy to drive hard and is very controllable (on a private course, of course officer )

Depends on the purpose I guess. With no drive to the front wheels a locked rear diff will make the vehicle very 'twitchy' at speed, it even affects the vehicle under braking too. If you've got a wheelie chassis (or a chassis capable of wheelies) then give it a try - locked and unlocked.

My 10T brushless Blackfoot could not keep pace with a 1:18 HPI across a field because I couldn't unleash full throttle without it spinning out wildly. It was depressing! With the diff unlocked again (geared diff) it did much more spectacular wheelies and was far easier to drive - even under full throttle. The bigger problem thereafter was slowing down enough to go around corners!

If it's just low-speed then locked will be fine though and give more traction in most conditions.

[derv_scaler]

The thing is though, when under braking you would be braking with both rear wheels with a locked diff, with an open you'll only be braking while you have traction on both wheels, as soon as one is off the ground or sliding you have no braking at all as the motor stops and the wheel with grip will just spin the other wheel backwards.

I recently built a Grasshopper and was experimenting with open and locked diffs, with an open diff you could pin it wide open across grass and make reasonable progress, but I could hear it wheelspinning the whole time, with the diff locked it hooked up much better and was faster across the same grass.

With the open diff on dry concrete you could apply full steering and get some speed up, but when the brakes were applied the inner wheel would lift off and the inner rear wheel would spin backwards due to the motor being stopped and the differential gear doing it's thing.

The spinning out example you gave highlights the positives of a locked diff, IE you are making much more efficient use of the available power from the motor, with an open diff you'll just be wasting that power by spinning a wheel, so you need to drive more gently to make the same progress as an open diff on full throttle.

Open diffs need a different driving style to a locked or limited slip diff, but I would agree that a locked diff is less forgiving, much like any other performance improvement..

Back to the original question, I've got an XC chassis'd Pajero (looks to be the same chassis as a CC-01) that I've modded a bit and have through bolted the gear case as the threads were stripped, it's currently running a brushed crawler motor through an HPI 7:1 reduction gearbox, so masses of torque and nothing has broken on it yet.

You'll want to replace the plastic axle link bars, they're quite flexible as standard, I made some myself but they need mounting differently to maximse articulation, but they are as articulate as the standard version.

There's so much you can do with this chassis, I started a project to replace the XC chassis entirely and mount a 3 speed transmission as I have a spare body, but I need to revise the geometry a little.

[emory70]

Thanks for the input. I'll be locking the diff for sure.

My project is based on an overpowered 2wd hot rod pickup, that is then modified for other nefarious activities. Destruction and ill handling are actually requirements of this build.

[bromvw]

Want more speed ? - rc4wd do a gearbox that bolts onto the motor that doubles the revs . http://store.rc4wd.com/12-Ultra-Compact-Gear-Speeder-Unit-for-540-Motor_p_766.html

you will need the pinion too .

I have effectively the same unit fitted in my cc-01 crawler - nice quality and easy to fit . You just need to trim 18mm out of the tub and relocate the battery .

[emory70]

Right now I'm looking at a $400+ build. I'll get it running and go from there.

[taliesin]

Has anyone tried this steering mod where you use two parallel arms from the servo to the top of the steering column? I saw this on youtube and wondered if it works any better. Granted, the most slop is on the lower rack, but still ... if it helps a little bit that is ok.

Looks like rather than the single arm servo horn they used a modified double sided horn (or cross with arms clipped off) on both the servo and the top of the steering column. You can see it pretty well here :