# Tamiya TRF421 et TRF421X

**URL:** <https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155>\
**Category:** Matériel et Technique\
**Tags:** trf421, trf, tamiya, trf421x\
**Created:** [Janvier 30, 2024, 8:09 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155 "2024-01-30T20:09:42Z")\
**Posts on this page:** 16\
**Page:** 2

<div class="post-metadata">

**Author:** ![T.Marco](https://forum.ircr.ch/letter_avatar_proxy/v4/letter/t/7ea924/32.png) [@T.Marco](https://forum.ircr.ch/u/T.Marco)\
**Post date:** [Novembre 11, 2024, 6:36 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/21 "2024-11-11T18:36:32Z")

</div>

@Georges top ce site!! je vais voir pour en commander si je n’arrive pas à avoir la pièce d’origine en Europe pour la prochaine manche!!

---

<div class="post-metadata">

**Author:** ![Georges](https://forum.ircr.ch/user_avatar/forum.ircr.ch/georges/32/12_2.png) [@Georges](https://forum.ircr.ch/u/Georges)\
**Post date:** [Novembre 27, 2024, 9:30 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/22 "2024-11-27T21:30:08Z")

</div>

J’ai reçu mes bras de porte-fusée en carbone pour mon TRF421 de chez H2RD, et malheureusement, la qualité n’est pas au rendez-vous…  
Tout d’abord, un emballage inapproprié, un simple enveloppe en papier bulle, ce qui n’aurait pas été gênant si je n’avais pas commandé également une platine supérieure.  
Ensuite, le trou oblong de ces bras est trop large d’environ 0.3mm. Ils sont donc inutilisables en l’état. Je vais essayer de récupérer ça comme je peux.  
En plus, les pièces n’ont pas été nettoyées après perçage, et les trous comportaient pas mal de poussière de carbone.  
Bref, H2RD, ce n’est plus ce que c’était…  
Je leur ai fait par de mon mécontentement, je n’ai pas eu de réponse pour le moment.

---

<div class="post-metadata">

**Author:** ![T.Marco](https://forum.ircr.ch/letter_avatar_proxy/v4/letter/t/7ea924/32.png) [@T.Marco](https://forum.ircr.ch/u/T.Marco)\
**Post date:** [Décembre 2, 2024, 7:53 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/23 "2024-12-02T19:53:26Z")

</div>

Hello j’ai commandé mes pièces d’origine chez @gulliverrccontrol en France, un magasin avec pignon sur rue très professionnel…

---

<div class="post-metadata">

**Author:** ![T.Marco](https://forum.ircr.ch/letter_avatar_proxy/v4/letter/t/7ea924/32.png) [@T.Marco](https://forum.ircr.ch/u/T.Marco)\
**Post date:** [Décembre 2, 2024, 7:57 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/24 "2024-12-02T19:57:59Z")

</div>

Et selon les contact un châssis alu pour le TRF421 serait bientôt dispo…

---

<div class="post-metadata">

**Author:** ![Bastien](https://forum.ircr.ch/user_avatar/forum.ircr.ch/bastien/32/2577_2.png) [@Bastien](https://forum.ircr.ch/u/Bastien)\
**Post date:** [Décembre 29, 2024, 1:45 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/25 "2024-12-29T13:45:12Z")

</div>

Je ne sais pas si je dois mettre ça dans ce sujet ou dans celui sur la TT02 mais il y a des gens qui s’amusent au japon!

Une TT02 avec la suspension de la TRF421!

[![](https://forum.ircr.ch/uploads/default/original/2X/c/c7385ad3260da50bfaaff0a08bed06a78883c346.jpeg "タミヤTRF421足の魔改造TT-02シャーシ！ 笠井421TTX紹介") ](https://www.youtube.com/watch?v=OJ1RraCwQy8)

---

<div class="post-metadata">

**Author:** ![Georges](https://forum.ircr.ch/user_avatar/forum.ircr.ch/georges/32/12_2.png) [@Georges](https://forum.ircr.ch/u/Georges)\
**Post date:** [Décembre 29, 2024, 8:50 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/26 "2024-12-29T20:50:57Z")

</div>

Apparemment, c’est la nouvelle tendance!

[![](https://forum.ircr.ch/uploads/default/original/2X/2/211f7316d70ef652b194a0b078aa9b681c90e4a2.jpeg "TT-02にTRF421サスアーム仕様") ](https://www.youtube.com/watch?v=BNgl_q4tt34)

---

<div class="post-metadata">

**Author:** ![Lonestar](https://forum.ircr.ch/letter_avatar_proxy/v4/letter/l/cc9497/32.png) [@Lonestar](https://forum.ircr.ch/u/Lonestar)\
**Post date:** [Janvier 12, 2025, 2:02 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/27 "2025-01-12T14:02:02Z")

</div>

Ça va parfaitement avec la musique, deux massacres…

---

<div class="post-metadata">

**Author:** ![Georges](https://forum.ircr.ch/user_avatar/forum.ircr.ch/georges/32/12_2.png) [@Georges](https://forum.ircr.ch/u/Georges)\
**Post date:** [Avril 22, 2025, 8:27 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/28 "2025-04-22T20:27:50Z")

</div>

Pendant ce temps au Japon…

> **[Goto & TRF421 Wins at SKT + Setup](https://kentech.wordpress.com/2025/04/22/goto-trf421-wins-at-skt-setup/)**
>
> The second round of the 2025 Speed King Tour race series was held at the New Next Rush Circuit in Japan over the weekend. In the end, Souta Goto – Tamiya Japan employee and TRF driver, ended …

et:

 ![490349537_1082741600549878_3554429122131272594_n](https://forum.ircr.ch/uploads/default/original/2X/0/05e8216981d6495ec30d007aee9f341d3b2efdf0.jpeg)

---

<div class="post-metadata">

**Author:** ![Bastien](https://forum.ircr.ch/user_avatar/forum.ircr.ch/bastien/32/2577_2.png) [@Bastien](https://forum.ircr.ch/u/Bastien)\
**Post date:** [Janvier 27, 2026, 10:24 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/29 "2026-01-27T10:24:03Z")

</div>

La version «&nbsp;X&nbsp;» arrive! Elle sera certainement présentée en détail à la foire du jouet de Nuremberg en février.

 ![image](https://forum.ircr.ch/uploads/default/original/2X/1/1de88e46effaa2056ab86d2179a59fa10f319c8e.jpeg)

(Source: [https://kentech.wordpress.com/](https://kentech.wordpress.com/))

---

<div class="post-metadata">

**Author:** ![Georges](https://forum.ircr.ch/user_avatar/forum.ircr.ch/georges/32/12_2.png) [@Georges](https://forum.ircr.ch/u/Georges)\
**Post date:** [Janvier 27, 2026, 10:56 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/30 "2026-01-27T22:56:06Z")

</div>

Des évolutions, la plupart intéressantes:

42391 TRF421X Chassis Kit  
The TRF series welcomes a new TRF touring car chassis kit. This R/C model assembly kit creates the 2 beltdriven 4WD TRF421X, the latest model in the line of TRF (Tamiya Racing Factory) chassis. Based upon the racing feedback, it employs the updated suspension and low center of gravity setup for superior performance.  
Aluminum motor mount  
Motor attachment position is 1.84mm lower than that of the TRF421 chassis kit for a lower center of gravity and more stable cornering, and a new design ensures accurate assembly.  
2.0mm thick aluminum lower deck  
The new lower deck is molded in popular aluminum, and allows lower motor attachment position for optimum balance of chassis flexibility and weight distribution.  
Compatible with the TRF421 chassis kit when using new motor mount and 2.0mm thick aluminum lower deck together.  
Upper deck  
Both types (one-piece and two-piece) of upper deck shape are updated for improved chassis flexibility.  
Compatible with the TRF421 chassis kit  
One-piece upper deck attachment  
Tubes, dedicated titanium low head screws and shims are used to attach the one-piece upper deck. Adjust flexibility by using 0-0.3mm shims.  
Compatible with the TRF421 chassis kit.  
Upper and lower suspension arms (new material) & front and rear damper stays  
Damper attachment positions are moved 1.0mm inside with new front and rear damper stays based upon the latest racing test results.  
Both upper and lower suspension arms are molded in carbon reinforced nylon (the TRF421 chassis kit features glass reinforced nylon) to ensure suspension  
flexibility and to improve stability on high temperature or high grip or carpet surfaces.  
Compatible with the TRF421 chassis kit when changing both damper stays and suspension arms.  
Drive shafts & drive train  
New front double cardan drive joint shaft and rear lightweight aluminum universal shafts feature bearings (drive shafts used on the TRF421 chassis kit feature swing shaft caps.) to limit friction and speed reduction.  
The design and materials of front direct cups and rear differential steel joints are also changed . (Materials are changed from aluminum to steel.)  
Like the TRF421 chassis kit, direct coupling and oil-filled gear differential are employed at front and rear respectively. (Currently-sold Hop-Up Option and Spare Parts can be used.)  
Upper arm mounts  
New upper arm mounts feature 1mm narrower pivot attachment width for improved cornering response, and upper arm attachment with bushings to adjust pitching,  
ensure accurate assembly and stability under vibration.  
Compatible with the TRF421 chassis kit.  
Knuckle arm  
New knuckle arms developed based upon the latest racing test result feature new hole positions for front and rear respectively. The hole for front makes ackerman position outward for more direct steering and the hole for rear makes adjuster rod attachment positions backward for optimum rear grip on low or middle traction surfaces.  
Compatible with the TRF421 chassis kit. When using knuckle arms included in the TRF421 chassis kit, 4 setup options (2 choices for front and rear respectively) are available depending upon road surface and driving style.  
Stabilizers  
Precision stabilizers can be chosen from 1.2 diameter (x2) and 1.3 diameter (x1) depending upon road surface and driving style.  
Compatible with the TRF421 chassis kit.  
Newly added receiver weight (20g) and 0.6mm thick battery weight (30g) ensure optimum weight balance. Receiver weight is attached by one screw, and also works as  
Receiver weight & battery weight  
cooling fan mount.  
Both receiver weight and battery weight are compatible with the TRF421 chassis kit.

Des photos, des vidéos et des informations complémentaires sur la TRF421X ici:

> **[42391 Tamiya TRF421X announced, first photos and official information here..](https://www.thercracer.com/2026/01/tamiya-trf421x-announced-first-photos.html)**
>
> Exclusive information of the Tamiya TRF421X

 ![dafb1574-8226-4749-88a1-a87541c4f164](https://forum.ircr.ch/uploads/default/original/2X/e/e1399b7e6cef3417913f0b3235b09624ff4cb437.jpeg)

 ![5bbcddd6-46a4-4fd3-bd8a-651f80b56c65](https://forum.ircr.ch/uploads/default/original/2X/b/b4c9b80c079d87725ea9749834ecf4a183b82ea4.jpeg)

> **[Tamiya TRF421X – Full Official Description](https://kentech.wordpress.com/2026/01/27/tamiya-trf421x-full-official-description/)**
>
> Following the first reveal of the brand new Tamiya TRF421X at the Spielwarenmesse 2026 earlier today, here follows the full official product description for the 421X from Tamiya. 42391 TRF421X Chas…

> **[Tamiya 42391 TRF421X Chassis Kit at Nuremberg Toy Fair 2026 - TamiyaBlog](https://tamiyablog.com/2026/01/tamiya-42391-trf421x-chassis-kit-at-nuremberg-toy-fair-2026/)**

https://www.youtube.com/embed/1UyGKfLJUnk?feature=oembed&wmode=opaque

---

<div class="post-metadata">

**Author:** ![Georges](https://forum.ircr.ch/user_avatar/forum.ircr.ch/georges/32/12_2.png) [@Georges](https://forum.ircr.ch/u/Georges)\
**Post date:** [Janvier 27, 2026, 11:17 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/31 "2026-01-27T23:17:59Z")

</div>

Livraison fin avril, déjà en pré-commande dans toutes les bonnes crèmeries, à moins de 590€ HT chez Tamico et 545€ HT chez Sakagushi Shop en Allemagne.

Ce qui est intéressant, c’est qu’il est possible d’implémenter les nouvelles pièces les plus intéressantes de cette nouvelle version «&nbsp;X&nbsp;» sans se ruiner (environ 80€ HT).  
Je pense plus particulièrement aux cardans à roulements avant et arrière (bien que ces derniers sont un peu moins indispensables) avec les sorties de spool et de différentiel correspondantes, et les bras de suspension chargés carbone inférieurs et supérieurs.  
Par exemple chez Sakagushi Shop:

> **[Vorbestellartikel](https://sakaguchinetshop.com/index.php?cPath=299)**
>
> Vorbestellartikel

Les prix en Suisse ne devraient pas tarder à être affichés.

---

<div class="post-metadata">

**Author:** ![Georges](https://forum.ircr.ch/user_avatar/forum.ircr.ch/georges/32/12_2.png) [@Georges](https://forum.ircr.ch/u/Georges)\
**Post date:** [Janvier 28, 2026, 6:35 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/32 "2026-01-28T18:35:44Z")

</div>

> **[Tamiya TRF421X – All the Updates](https://kentech.wordpress.com/2026/01/28/tamiya-trf421x-all-the-updates/)**
>
> Well, yesterday was finally the opening day of the Nuremberg Toy Fair – Spielwarenmesse 2026, and the TRF421X we had been expecting was finally revealed by Tamiya. On first look the reaction …

---

<div class="post-metadata">

**Author:** ![Georges](https://forum.ircr.ch/user_avatar/forum.ircr.ch/georges/32/12_2.png) [@Georges](https://forum.ircr.ch/u/Georges)\
**Post date:** [Février 1, 2026, 4:42 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/33 "2026-02-01T16:42:25Z")

</div>

L’interview de Kiyokazu Suzuki par Dai Sakagushi au sujet du TRF421X:

![](https://forum.ircr.ch/uploads/default/optimized/2X/7/7f0fafad0c549edd72a8dd445f52334414224bb2_2_690x388.jpeg)https://www.youtube.com/embed/gbpt46YCZAA?feature=oembed&wmode=opaque

---

<div class="post-metadata">

**Author:** ![Georges](https://forum.ircr.ch/user_avatar/forum.ircr.ch/georges/32/12_2.png) [@Georges](https://forum.ircr.ch/u/Georges)\
**Post date:** [Février 15, 2026, 5:30 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/34 "2026-02-15T17:30:40Z")

</div>

La Tamiya TRF421X de Souta Goto lors de la [TITC2026](https://forum.ircr.ch/t/titc-2026/622/):

> **[Red RC Events » Chassis Focus – Souta Goto (Tamiya)](https://events.redrc.net/2026/02/chassis-focus-souta-goto-tamiya-2/)**
>
> RC car news, views & race results

---

<div class="post-metadata">

**Author:** ![Georges](https://forum.ircr.ch/user_avatar/forum.ircr.ch/georges/32/12_2.png) [@Georges](https://forum.ircr.ch/u/Georges)\
**Post date:** [Mars 11, 2026, 3:26 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/35 "2026-03-11T15:26:02Z")

</div>

Sur les sites de Kentech et The RC Racer, il est maintenant possible de consulter la notice de montage du TRF421X:

> **[42391 Tamiya TRF421X manual Download Here](https://www.thercracer.com/2026/03/42391-tamiya-trf421x-manual-download.html)**
>
> 42391 Tamiya TRF421X manual Download Here

> **[Tamiya TRF421X Manual Available](https://kentech.wordpress.com/2026/03/11/tamiya-trf421x-manual-available/)**
>
> With one and a half months passed since the TRF421X Chassis Kit was introduced by Tamiya at the Nuremberg Toy Fair 2026, and still some time until the car kit will be available, I’m happy tha…

Et force de constater qu’au delà des évolutions annoncées, il y a d’autres surprises en comparant les notices du TRF421 et du TRF421X, comme par exemple:

- les sorties de spool sont d’un dessin étrangement similaires à celles d’Axon;
- un Té de renfort arrière est livré d’origine;
- les supports de roulement du différentiel et du spool sont différents pour offrir des hauteurs intermédiaires par rapport aux extrêmes des pièces du TRF421;
- les pistons des amortisseurs qui sont toujours à quatre trous, mais sont passés de 1.1 à 1.2mm…

Seul regret, les joints o-ring des amortisseurs qui restent les mêmes, à remplacer dès le montage par des Axon, ou mieux, des Infinity, ou encore mieux des X-ring G-Force.

---

<div class="post-metadata">

**Author:** ![Georges](https://forum.ircr.ch/user_avatar/forum.ircr.ch/georges/32/12_2.png) [@Georges](https://forum.ircr.ch/u/Georges)\
**Post date:** [Avril 10, 2026, 9:09 UTC](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155/36 "2026-04-10T09:09:32Z")

</div>

Modèle de pré-série, présentation par [sakaguchinetshop.com](http://sakaguchinetshop.com/?fbclid=IwZXh0bgNhZW0CMTAAYnJpZBEwNGVxdVFBN09hUk9hMk5PdXNydGMGYXBwX2lkEDIyMjAzOTE3ODgyMDA4OTIAAR6McltombR8hE9AQJ-EXjSdjIazVoOuJUBR9N-pv6iS9fbNSkGzlIVMWqsNNg_aem_cM7aWlM7rJFoh8bT8RUFjQ):

> **[TRF421X #42391 Build Up + Tech Insight – RC-Race-Blog by Dai Sakaguchi...](https://wordpress.sakaguchinetshop.com/2026/04/04/trf421x-42391-build-up-tech-insight/)**

 ![SArms-R-scaled](https://forum.ircr.ch/uploads/default/original/2X/f/ff731f899927f0aff82aecc49f51dafa786669e8.jpeg)

 ![ASarms-F-scaled](https://forum.ircr.ch/uploads/default/original/2X/4/49e518e84e5c14c1612b6fdc509c9c771ee590a9.jpeg)

> **[TRFworkz Video Episode 17: TRF421X First Drive at Arena33 in Andernach –...](https://wordpress.sakaguchinetshop.com/2026/04/06/trfworkz-video-episode-17-trf421x-first-drive-at-arena33-in-andernach/)**

![](https://forum.ircr.ch/uploads/default/optimized/2X/7/781c2db39fa1dd01ef63586bb1c4dcb597f1398c_2_690x388.jpeg)https://www.youtube.com/embed/VyqMxSCxnbs?feature=oembed&wmode=opaque

[Page précédente](https://forum.ircr.ch/t/tamiya-trf421-et-trf421x/155.md?page=1)
