TT-02B RWD?

[skom25 2781]

Hi,

Yesterday when I stripped down TT-02B to swap parts to On Road version, I started to think about RWD.

Balance of chassis looks quite fine and RWD Buggy is always fun to drive. Have anyone of you tried to leave only RWD in TT-02B?

My idea is to remove all drivetrain parts and leave just that which are necesarry.

[Mad Ax 11602]

I'm really intrigued to hear what others think about this.  My instinctive answer is "no, it won't work" because "RWD buggies have different geometry."

Back in the old days, at least, that was true.  2WD buggies had the motor hanging about the back for better traction, but with modern tyres, track surfaces, and chassis designs, that's no longer necessary - most modern race buggies are mid-motor, and have been for a decade.

So the answer to this, really, is "try it and see" - but to really see, I think you need to compare it with a mid-motor RWD buggy of a similar pedigree, and that's where it gets tricky.  It would be totally unfair to compare it against a modern RC10, since even the basic version is a thoroughbred race buggy with decades of development on it.  You could compare it to an RC10 B5, since that was released only a year after the TT02B and is mid-motor, but even then, the TT02B was a basic parts-bin basher and the B5 was a dedicated race buggy.

You could compare it to Tamiya's basic RWD bashers of the era (the DT-03 was released a year after the TT02B) but that's a rear-motor layout.  I guess Tamiya never bought into the mid-motor thing at the basher level.  But it would be interesting to see how it compares.

I'd guess you'd need to make some setup changes to get the best out of it.  RWD buggies are usually pretty soft up front, and generally you'll have more steering lock on an RWD setup.  With the front driveshafts removed you can probably get more lock, maybe with some trimming.  Also you'll want to consider narrower front wheels and appropriate tires to get the best RWD driving experience.

Here's a question: does the TT02B have any kickup?  I don't have one, so I can't check.  I've just looked over ay my shelf, and the Top Force and Manta Ray appear to have the same kickup as the Super Astute, and these are from the same era.  However the DT-03 looks to have more kickup.  I don't have a modern 4WD to compare against, but my gut feeling is the TT02B probably won't have as much as a contemporary 2WD, and it would be hard to dial it in without significant mods.

But as I said above - I'm really interested to see how this works out.  You may find that for a backyard basher, just pulling out the front gearbox stuff is all you need to do.

[Aerobert 2328]

Member @OoALEJOoO has done this with a TT-01E. I think it should be transferable in certain parts to a TT-02. He also started a thread regarding a one-way diff as far as I remember. 

Edit: After reading the other answers I realized that the question was for the TT-02B. I've only read 'onroad' and missed the B. I leave it here however as I think it might be helpful anyway. Will read the text better next time. 

Edited March 5, 2024 by Aerobert
Didn't read the question properly.

[Pylon80 4345]

@skom25 I made RWD conversions of my TT-02 and TT-02 Type S in the past. It works quite well but that was for on-road. The subject comes back quite often here on TC.

I don't know buggies but if the weight bias is a concern as @Mad Ax suggests, you can get a TT-02 at 40/60 like a RWD buggy by installing the ESC on the rear bumper (obviously you need to lengthen the wires) and using a shorty pack. Another cool project that I sadly didn't document in a thread although there's probably pictures knocking around in "what have you done today".

 

[Kowalski86 5090]

Mid motor 2wd would be fine on asphalt, but for dirt you ideally want 4wd or rear motor rwd or you might have a lot of wheelspin.

[OoALEJOoO 3702]

Welcome to the fun & never-ending world of TT-02 tweaking

As @Aerobert mentioned I have extensively played with TT-01 and TT-02 on-road RWD conversion and they work wonderfully. Flipped front one-way helps with 4WD braking at the expense of cornering stability. Alternatively, just stiffening or locking a free-wheeling front diff does not help on braking (still RWD) but makes the car very stable in cornering. A simpler third option is just disconnecting the front drivetrain -this is the worst of both worlds, although still much more drivable than say a M-06 which is designed to be RWD!

Transferring that to off-road might be a different matter though. Loose surfaces favor loose front diffs to prevent mid-corner understeer and perhaps even combat general on-power oversteer if the surface is not too loose. This makes me think that perhaps the flipped one-way is best here as it will help with braking. Just disconnecting the front drivetrain is not a bad thing to try for starters. If you decide to keep the front diff, make sure you plug the opening towards the prop-shaft. A plastic bearing with tape on its hole works great.

This is what makes the TT-02/B platform such a great model. You can really experiment all sorts of things quickly and with minimal cost. Give it a try and let us know how it goes!

[skom25 2781]

Yesterday I finished 4WD version rebuild.

Today I converted it to RWD 🤔

[Kpowell911 2655]

Took me a while to work out what happened there! How’d you do that?

[skom25 2781]

Full speed, concrete block. Should I add more? 🤔

[alvinlwh 8127]

.

[OoALEJOoO 3702]

@skom25 Sorry to hear about the accident. Will surely make a fun anecdote for the future . That's the great thing about the TT-02 even the chassis is low-cost to replace.

Looks like you could get a lot of extra life out of your Dual Blocks if you flip each tire before you punch a hole through the rubber (given only the inner half is worn, especially the rear).

[Pylon80 4345]

11 hours ago, skom25 said:

Yesterday I finished 4WD version rebuild.

Today I converted it to RWD 🤔

I would check the front toe, seems a tad too much 😅

The best thing about the TT-02's is the 5$ lower deck. Hopefully not too much other damage and you'll be back on the road soon 👍

[skom25 2781]

2 hours ago, Pylon80 said:

I would check the front toe, seems a tad too much 😅

The best thing about the TT-02's is the 5$ lower deck. Hopefully not too much other damage and you'll be back on the road soon 👍

I did summary on build Topic. Unfortunately there is much more 🙄

[Honza 1318]

On 3/5/2024 at 7:43 AM, skom25 said:

Hi,

Yesterday when I stripped down TT-02B to swap parts to On Road version, I started to think about RWD.

Balance of chassis looks quite fine and RWD Buggy is always fun to drive. Have anyone of you tried to leave only RWD in TT-02B?

My idea is to remove all drivetrain parts and leave just that which are necesarry.

A bit too late to the topic (sorry about the accident) but this is basically what X-ray did with their first 2WD buggy - They took the XB4 and throw away the front drivetrain and tweaked the geometry. That car was intended for indoor, for dirt, they introduced the XB2 and later did carpet version of that.