Tamiya do actually give the actual dimensions of the bearing if you look closely. Build enough tamiya kits and you will start to pick up on their nomenclatures.



1280: 12mm OD 8mm ID
1150: 11mm OD, 5mm ID
1050: 10mm OD, 5mm ID

The only thing the dont give is the thickness of the bearing, but you can assume all of them are 4mm thick unless other wise stated like the 1050 bearing shown above.

Sorry, wrong post..

What do I want in the front....one way, spoiler diff. I want to race my new tt02 in tcs black carpet

Any help wood be great

Spool as a base setup, diff if you want / need more turn-in. One-way is hardly used nowadays.

Will I need different drive axels if i swap them out?

Same axles fit both. However, when running the spool, do not use the plastic dog bone pin covers. You will break the outdrive sooner or later. Instead, use the thin slots on the outdrives with just the pins on the bones.

On the topic of racing seriously a TT02 (in my case the SRX version, in the TamiyaCup champ. in Belgium), I hesitate to test the shorty configuration in order to make the car a lot less heavy. For now, I'm using a long pack 8400mAh IP battery. When I built the car, I weighted the electronic side of the car (i.e. : motor (incl. motor mount), fan, esc, RX, servo (incl. one-piece alu servo holder),...) and it came around a bit more than 300g (330g I believe).

My motor (spec) weights around 178gr. So I'm thinking using an IP shorty 5000mAh (around 173g) at the rear to replicate the motor weight distribution at battery side. I also consider putting the ESC in front of the battery to compensate the servo. In theory, this should lead to a correct L/R balance (almost).

I've read everything related to battery size in the TT02 and I'd like to get some advice from those running this car. What are the pro's / con's of both configurations ? Why would you prefer one over the other ?

Thanks for the experience sharing !
G-rem

Ive ran the car with electronics on one side and shorty battery on the other and the motor side is almost always going to be heavier. I put the car on balancing pins and deliberately tilt the car to the battery side just to watch it teeter back to the electronic side. Im not running super light weight battery, a big or heavy ESC or have heavy gauge wire either. Just a Hobbywing XR10 stock spec with 16awg wires and a 5500mah battery weighing around 200g.

After moving the ESC over next to the motor and having the battery up front the balance is more even left to right.

Thanks Disaster, meaningful input.
Did you try to put the shorty battery at the most rear position and the ESC in front ? What difference in behaviour does that make ?

After posting my previous message, I've weighted the electronic again and it came up at 340g whereas my long pack IP 8400mAh battery is 335g, so almost perfectly balanced. However, like so, the car weights in total more than 1.4kg without the body.

I know a shorty will not be able to deliver the same power output as long as a normal long pack. Especially for stock racing 17.5t. However, by using a shorty, I can shave up to almost 150g. And I'm leaning towards the "light is right". Moreover, I saw that at the EOS in Daun this past weekend, mod 4x4 drivers were using 4.5t motor with shorty LCG less than 5000mAh for the race. This should be fine then I guess.

Regards
Jeremy

I ran the car with battery on one side and electronics on the other for a while and honestly the car handled fine, MAYBE its a little more sluggish turning left than right but I honestly didnt really care. I was having too much fun just running the car on the track with friends. After moving the ESC to the battery side, the car drove very similar to before, maybe a bit more balanced and easier to drive.

I never tried putting the battery to the rear and having the ESC to the front but keep im mind with motor wires reaching that far, it will undoubtedly tub against the center shaft and cause issues down the line.

With my setup, the car weights under 1100g without the body, and under 1350g with a tamiya body.

I also tried full size lipo (6000mah) and lcg lipo (4600mah) on my stock TT02 for Production. Even tried the lcg lipo with esc on the same side and to me didn't feel right on the track.
Sometimes you have to experiement and see what feels right to you while driving. My times weren't any faster with the lcg lipo and esc on one side compared to just a full size battery. Could it be because the car handled better with a larger battery (also had more mah towards the end of the race).
My Production TT02 felt more planted with more weight on asphalt.

Thanks, that's the usual comment I've read about running the TT02 with a shorty (and thus what makes me hesitate). However, I cannot imagine that 100 -150g less of the total weight will not be an advantage for this car. I guess I will have to try to figure out then. Thanks for the input guys !

Regards
G-rem

Hi G-rem,

I guess that the heavier battery has a higher average voltage. That should easily
compensate for the higher weight (depending on the track).

Aby setup tips for the SRX on asphalt?

Here