Currently, Tamiya's well-rounded and best buggy transmission + gearbox?

[Mechanic AH]

Hi all, been thinking about some of the gearboxes and transmissions on Tamiya kits I've built and it would be nice to hear from the experienced or those who've driven many Tamiya RC cars about your thoughts on the topic. What do you think is currently the best (well-rounded) buggy transmission/gearbox Tamiya has to offer? "Best" like a jack-of-all-trades that passes a fair amount of criteria. I understand there's no perfect one but what would your transmission choice be and how would you score it from 1-5 with the following criteria:

Transmission/gearbox model: 
(score 1 to 5)
Current:
Cost:
Durability:
Performance:
Design:
Drive:
Options:

Current:
- Parts are still plentiful and easily available from many merchants 
- Continually being produced so there's no shortage of parts
- Every component/part of the gearbox is easily available 

Cost:
- Affordability and low cost for easy replacement of worn or damaged parts

Durability:
- Can easily take a beating from jumps to hot or high KV motors and some abuse (this includes internals and gearbox case)
- Ideal if gearbox is sealed to help keep dust out
- Good and durable materials

Performance 
- Options for gearing
- Can be geared high for speed runs
- Possibility for some track use

Design
- Doesn't need a lot of modifications/hop ups to make it work at its optimum performance
- Pragmatic and uncomplicated
- Maintenance is easy
- Good design

Drive
- Smooth power delivery
- Good differential (either gear or ball)
- Quiet gearbox
- Tight internals

Options
- Availability of aftermarket parts
- DIY options

One thing I haven't given much thought to is the drivetrain, either 2WD or 4WD is fine, and are there on-road transmission/gearboxes that can be used for off-road I'm missing out on? Thanks for your input.

[DaveBuildsRC]

There two or three Tamiya bbx bb01 buggies gearboxes used in the builds sections. Seems like a good trans too. 

[Kowalski86]

Outside of the DT-03s chassis being somewhat brittle and only 2 gearing options, I think it checks most of these boxes. It's cheap, robust, and just "works" once you weight the nose down and add bearings/better pinion.

[Thommo]

Durability, design, drive and performance it’s the DB01 for me.  Clearly failing some of the other criteria, I give it a 4. 
 

DT02 and the TTC both original and 2018 are my other favourites.

[GTodd]

Dyna Storm with TD2/4 slipper for 48P conversion, TFR201 trans. Race bread bullet proof gearboxes that can take the latests lipo and Brushless horsepower. FOr 4wd DB01/TRF 5XX belt drives. 

[skom25]

3 hours ago, Kowalski86 said:

Outside of the DT-03s chassis being somewhat brittle and only 2 gearing options, I think it checks most of these boxes. It's cheap, robust, and just "works" once you weight the nose down and add bearings/better pinion.

It is also really nice in terms of dirt protection. I ran DT-03 on asphalt, sand/ dust where I was not able to see car, Off Road and even once turned it into Submarine. In all cases, the worst what I found was some debris where parts join together. Nothing more.

It is also simple and has steel diff.

Unfortunately, you can fit only 17T and 19T pinion.

[markbt73]

Yeah, my favorite is still the Grasshopper/Hornet/Lunchbox etc gearbox. Cheap, simple, indestructible, throw as much power as you like at it and it just says "ok." Only needs six bearings for a complete driveline, motor to wheels. Gearing options are limited to 10t or 18t pinions, and it's a live axle, so not much you can do with the suspension, but it will spin smoothly until the heat death of the universe. And if you expand your definition of "track" to include a dragstrip, it can do that too.

Second place: Clod, for basically the same reasons. What can I say? I like things simple.

[BuggyDad]

After getting a BBX I decided to use that gearbox in my home made buggy. It's not cheap but:

- it shares diffs with TD2/4, XV01, M08 and a few more besides, so all the options there, and other gears with XV-01 (maybe others?). 

- how it fits is versatile and simple - 4 screws down to a flat floor, equally spaced about the diff, and then a point to brace to in front, 40mm up. Quite unlike most Tamiya gearboxes I've seen which are very integrated into their chassis, so less versatile for using elsewhere. At least two other TC members have used these gearboxes in other cars too. 

- slipper available and that shares pads and spur (so almost endless gearing options) with some others, I think including Associated, although it is not itself shared. 

I haven't run either of my BBX gearboxes enough to comment on durability but I've no concerns. 

The gearbox I have put the most miles into is the DT-02/3. It's a quite different grade to BBX obviously but as others have said above its gears are robust (mind you, aren't most Tamiyas?) and it's well sealed. I am OK with its limited gearing which seems expected at that end of the market, covers us for both buggy and truck wheel sizes and gets a beginner perfect mesh every time. I think it's a slight shame though that it wasn't dimensioned to take a sealed gear diff option (although one has just emerged with only light modification). I also dislike gearbox casings that incorporate suspension mounts, because I think that just puts undue stress on the part, although I think we have only broken one in loads of brushless running. But overall I think it scores quite well for a budget model. 

Like the DTs, the Blitzer gearbox is robust in gearing, but geared for big wheels only (unless you get the Bear Hawk version which is long since discontinued), has only an open diff option and it incorporates the suspension mounts (which I've broken twice in a low mileage car, the first time it hadn't had a hard hit in its life but I had replaced the very soft arms with much stiffer ones). It's also a two gear setup with the motor out back, so it squats pretty hard under power. I think one could design out some of these limitations even in a budget box as this is. It's a little frustrating, so even though it's simple and probably robust enough for its intended use, I would score it a bit lower. It's maybe a simpler/more versatile connection to the chassis though. 

[SlideWRX]

DT-02/DT-03:

Current:5
Cost:5
Durability:4.9 - 'sealed' but stuff still finds a way in
Performance: 3 - 0.8mod/32pitch instead of most common in racing 48p.  Only two gear choices officially (17t & 19t). See below.
Design:4.5 - Needs to open up the area around the motor for ventilation
Drive:3 - 0.8 mod is a little louder than 48p. Gear diff & ball diff both available.  Gear diff isn't sealed though, gotta use putty to stiffen it.
Options: 1? don't know of many options for it.  No slipper spur available. Control arm mounts are molded in, which may interfere with custom setup. Spur gear is molded to next gear which makes replacing/modding difficult.

The stock spur is a 55t/19t molded all-in-one.There is a 52t 3d print on thingverse; I haven't tried it. It turns out the Stadium Blitzer spur is 50t/19t that fits well enough. (P#9335111)  I really wish they had put more pinion holes into this thing; maybe a 13t & 15t & 21t in addition to the 17t & 19t.  I drilled some holes to put my own 15t pinion in there to run lunchbox tires on a stock-ish motor so hopefully it won't burn-out.

Gear Ratio
Spur		17t spot	19t spot
55t		9.3(17t)	8.3(19t)
52t		7.5(20t)	6.8(22t)
50t		6.6(22t)	6(24t)

[Kowalski86]

4 hours ago, SlideWRX said:

DT-02/DT-03:

Durability:4.9 - 'sealed' but stuff still finds a way in
Performance: 3 - 0.8mod/32pitch instead of most common in racing 48p.  Only two gear choices officially (17t & 19t). See below.
Design:4.5 - Needs to open up the area around the motor for ventilation
Options: 1? don't know of many options for it.  Control arm mounts are molded in, which may interfere with custom setup. Spur gear is molded to next gear which makes replacing/modding difficult.

 

32P Gearing is good for durability, but you're right that the DT02/3s motor ventilation isn't great, some people run 550 cans with fans in them.

The molded in control arm mounts are a knock for durability, since if one snaps that means a new chassis or gearbox. At least the DT03 has that U-shaped bracket up front. Another knock would be the ABS plastic, the BBX is nylon which is much better for a buggy.

My Neo Fighter was pretty well sealed (its hard not to be with such a narrow chassis), but my DT-02 Holiday Buggy would pick up every leaf or drop of water that it ran over, I can't imagine the Nissan truck being any better either.

 

[Mechanic AH]

Thanks for the replies. Sorry for the late response. It looks like the solid options are the BBX and DT02 trans/gearboxes for ticking most of the boxes. I have yet to build the BBX and TD4 (which I do have) so I probably will know what would be preferable but it looks like the BBX is more popular. As for the DT-02, it's a fun and solid transmission backup (and cheap parts to replace) but was hoping there'd be another alternative. Interestingly, the old Grasshopper gearbox is somewhat like it, pretty solid. I just wish there was just more flexibility. Any DBxx or TRF stuff doesn't seem a good choice as it only ticks the performance aspect and fails on cost/replacements. I guess I'll see what the BBX gearbox has in store.

[Sgt.Speirs]

I'm a big fan of the (modified) TRF201 gearbox of @ThunderDragonCy. This was the basis for my gearbox conversion for the King Cab/Monster Racer/Astute and the Dyna Storm/Dyna Blaster.

My reasons why?

• Compatible with TD4/TD2/BBX ball differential
• Compatible with TA06 / XV01 oil filled gear differential
• Compatible with TRF201 slipper clutch set (TA-54260) and TD4 / TD2 slipper clutch set (TA-22031)
• 48DP pinions
• 48DP spur gear options (79T, 86T & 91T) depending on the gearbox and gear ratio

The only "negative" aspect of this gearbox (which is for no negative point), it's only available as a 3D printed part.

If you cannot cope with this circumstance, the BBX gearbox is my next favourite gearbox, because it is share the same diff options (ball and gear diff) and the slipper is similar (48DP spur gear, same slipper pads,...). 

 

My rating:

Current: 5

Cost (for purchasing): 2   (slipper 40€, diff 35€, gear case 15€...40€,...)
Cost (for spares): 4

Durability: 5
TRF201 / TRF211 approved!

Performance: 4.5
Not suitable for high speed runs because of limitations of the pinion/motorplate)

Design: 4.5

Drive: 4

Options: 5
DIY options on Shapeways from ThunderDragonCy and Sgt.Speirs