Yes it is required

Other than it simply covering the spur gear, it also functions to support the top of the motor mount and retain the rear prop shaft bearing.
Even if you wanted to omit it, there is no TCS legal option part that substitutes for those other functions.

Its too bad Tamiya doesn't make an optional blue aluminium or carbon fiber piece to hold down the rear prop shaft bearing and eliminate the rear cover. This would make it easier to tech at TCS events to make sure folks are running the correct pinion and spur gear. Plus it would reduce weight ...LOL :lol:

without it, the bearing for spur gear and input shaft cup, will not be secure. Any brace or cover you come up with to hold it in place would be considered illegal. So you would need to run it

The following link is for an aftermarket piece that replaces the spur gear cover on the TT02. This part IS NOT TCS LEGAL

https://www.thercracer.com/2020/07/t...ear-cover.html

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There is no real benefit to removing the spur gear cover on the TT-02 unless you are running classes such as USGT or VTA where small spurs and large pinions are being used with brushless motors.

Here is a link discussing how to modify the stock TT-02 gear cover when racing those classes. Please note that this link discusses using aftermarket parts and the modifications to the spur gear cover IS NOT TCS LEGAL.

https://www.thercracer.com/2014/04/t...ta-blinky.html

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Here is a link to a great guide for club racing a TT-02. It shows most? of the available upgrades the chassis. If you have no plans on racing a TT-02 in a TCS race or running in a class that uses TCS Rules, it contains some great info.

https://www.thercracer.com/2014/08/t...-and-tips.html

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FYI: I am not affliated with The RC Racer or that website. However I have found this website very useful when upgrading my TT-02 chassis.

Hope this information helps.

Thanks guys…figured I’d ask those in the know.

new Carson Deck is nice but the 5th screw cant be mount on Type S, SR and SRX because the aluminum steering would touch the connection tower... when finding a solution I will post ist (TEC conform, just Tamiya and Carson parts)
https://cimg4.ibsrv.net/gimg/www.rct...9601cd3b96.jpg
https://cimg5.ibsrv.net/gimg/www.rct...8691b4db3f.jpg
https://cimg6.ibsrv.net/gimg/www.rct...5651f80cbb.jpg

Here is a link to the Carson TT02/TT02S upper deck (https://www.carson-modelsport.com/ca...-en.html?wse=1) and a link to the pdf manual...

https://cdn.simba-dickie-group.de/do...arbon_Deck.pdf

The simple solution to using the "5th screw" on the Carson TT-02 carbon upper desk is to swap out Tamiya 54965 (https://www.tamiyausa.com/shop/optio...-steering-set/) with either the stock plastic parts or Tamiya 54574 & Tamiya 54575 or Tamiya 54752 (https://www.tamiyausa.com/shop/optio...cing-steering/)

If you check out the following page, you can see a TT02S kit with TRF419 suspension with the basic TT-02 aluminum steering installed (https://www.thercracer.com/2020/03/u...02-type-s.html)

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The issue with with using an upper deck when using Tamiya 54965 steering is that of the 2 upper decks I've seen, they use the front bearing cover holes to mount the stand-offs to the upper deck. Here is a different design upper deck where you can see everything installed. (https://www.thercracer.com/2019/06/t...-top-deck.html)

The obvious solution would be to either redesign the front part of these aftermarket upper decks so that the stand-offs connect where the steering arms connect to the chassis. In the case of the Carson deck, you would just need to design a different/wider carbon fiber piece for the "5th screw" instead of redesigning the whole upper deck. You might also need to redesign/shorten the stand-offs.

I do not have an upper deck for my TT-02s kits, but I do have the Tamiya 54965 steering and it is better because it has very little bump steer through the entire suspension travel.

Here is a pic of the steering on my car from the top that shows how the newer steering bridge ends up over the screw for the front bearing cover...
https://cimg0.ibsrv.net/gimg/www.rct...96ea8d9553.jpg

Check out the top deck in this picture of an HPI Pro 4 car. You can see how the top deck connects above the steering arms. This is what I mean you could do with either a redesigned TT-02 top deck (or redesign the "5th screw" cross brace on the Carson deck)

https://cimg6.ibsrv.net/gimg/www.rct...fe785e434c.jpg


Here is a link to the HPI Pro4 thread here on RCTECH...

https://www.rctech.net/forum/electri...ispreloading=1

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Oh and in case people new to haven't seen how far someone can take a TT-02, check out the TT02-KR thread here on RCTECH...

https://www.rctech.net/forum/electri...-tt-02-kr.html

There might be a new deck coming very soon ;)

Put a castle brushless system in my TT02 and took it out for the first time this morning... OK number but I'm sure it has more in it! looking forward to getting to 100!

https://cimg7.ibsrv.net/gimg/www.rct...0e5d018c4f.jpg

https://cimg2.ibsrv.net/gimg/www.rct...e26122317f.png

You just missed out on the Poor Boys RC challenge on YouTube.

those tyres are not going to hold up to 100. At 70, it’s already ballooning a lot. You’re going to need belted tyres or foams.

they are belted.

Thought they were Tamiya, as they resemble their 24mm.. They’re not Tamiya then.