I’ve been looking for white bumpers for my Yokomo and RC10s after I saw this picture on time tunnel.

http://www93.sakura.ne.jp/~time-tunnel/09-8-2-3.html

got nothing. but I got a Kydex sheet today from my friend Aaron. it’s the place we got the sheet from

https://www.mcmaster.com/acrylic/pvc

it’s 1/8″ sheet which has the same thickness with the original yokomo material.

the part # is 8650K113
white, 1/8″ thick, 12″ x 12″, and cool

they usually use a electric oven for DIY kydex job, but I put it in a boiling water for a minute or so. and put it on the original bumper then pressed.
it was quite easy to bend. also the sawing was, but the trimming job wasn’t to me. but I noticed I got wrong idea about bending. all the bumpers I made were slightly crooked and need to be re-bent. the bent material goes back to the original flat shape so easy in a boiling water.

the bumpers on 834B, 870C, and, Works 91/93 are slightly different but, basically same. and, you can make more than 12 bumpers with one 12″ x 12″ sheet

it works for RC10 as well

MR-4BX series has been produced for only a couple of years. the first version came at ’06 and replaced with B-Max4 which was different from previous yoke buggies at ’08.

MR-4BX series is like the last blood of traditional Yokomo to me. and I see the same blood on Jconcepts BJ4. 

I have managed to get a nicely used Worlds edition last month. and took some pics with my factory edition. they both came at ’07.

 

the differences between them are main chassis, F/R shock towers, top deck(s), steering, rear bulkhead, and a few misc parts

 

 

Front End

 

MR-4BX Worlds came with a new camber mount which allows only the longest upper rod setup. also the steering is different than previous 2 versions

this new camber mount can be installed on older versions as well

 

the original and Factory edition’s front tower provide 6 points of upper rod mount position. the tower is compatible with the original through Worlds. and the inside position provides pretty much same result as Worlds’ front camber mount

 

 

 

 

Steering

 

the steerings are quite different. I hope I can feel the difference while I’m running this Worlds edition. but, didn’t have a chance so far.

 

 

this steering was introduced with MX-4. prototype MX-4 still had older servo saver. and the first time I saw this was in MX-4 kit.

but the difference is the angle. this steering system on MR-4BX is tilted for better handling.

 

 

 

Chassis

 

this 2 piece structure was came from the prototype and applied to the production models through the 1st and Factory edition. but Worlds edition came with 1 piece chassis

 

MR-4BX Worlds came with this 1 piece chassis with 2 extra holes for new steering system. please ignore the stainless screws on the Factory chassis. I’d go back to the black steel screws.

 

 

 

 

 

Top Deck

the top deck, now it covers the rear belt. and new camber mount is here

Factory edition had 2 piece top deck like the original version. but the rear piece was improved that older one has clearance problem with the belt

the rear top deck from the ’06 original version

 

 

Rear Shock Mounting

there were a few guys tried this before Worlds edition came. the shocks were moved to the back end of the car.

also they put a camber mount like the front end

the original and Factory edition had same suspension geometry. the shocks can be moved to the back end with this stock mount plus a few tricks

the new aluminum part which holds the the shock tower is changed along with new bulkhead and camber mount

 

 

 

related links
http://www.oople.com/rc/photos/reviewbx/index.html

http://www.oople.com/rc/photos/review501x/page08.html

 

I’m running this small version of Buggy Champ – Rough Rider for years. yes, it’s small and cannot run on the bumpy tracks.

and I watched it’s not bad on the the rally circuit where I’m running my old RC10 and 834B runners.

this tamtech champ came with the plastic spring dampers. buggy champ runs like tamiya grasshopper with the stock shocks. actually it runs better than grasshopper.

google found me Losi Mini-T shocks weeks or months ago. an I’m running with the shocks. losi shocks turned this tiny champ into a racer.

I got myself this front axle mod idea from rc10talk.com forum when I wanted to put Yokomo 2.2″ wheels on my RC10 runners a couple of years ago. Associated #7222 axles are everything actually. there are not much left to do except for getting the axles if you want to use B4 or JC rulux wheels

longer axle on the right side is ASC7222 that makes you can use none-offset wheels like B4’s, Yoke 4WD’s, and more

Yokomo made TH-1 wheel adapters for RC10. early TH-1 came with front adapters as well. but later TH-1 didn’t

got this after I trimmed the each side of Ultima front hub from TH-8 package above. the diameter is “slightly” larger for 3/16″ bearings. but the tiny play (gap) was fixed with Loctite. then I’v been using the hubs without a issue

RC10 axles and wheels

got the pictures from my RC buddy yesterday. unfortunately, I didn’t get any information of the source where the pictures came from

Magazine: Model Channel
Issue: May, 1983
Title: RC Car – New Kit(s) Info

use this list for searching yahoo japan auctions and other japanese sites
try http://auctions.yahoo.co.jp/
and there are lots of english service like this one
http://www.rinkya.com/  

Yokomo ヨコモ
Dog Fighter ドッグ ファイタ
Prototype プロトタイプ (or プロト)
Hot laps ホットラップス
Front フロント
Rear リア
Bulkhead バルクヘッド
Universal ニバーサル
Axle(s) アクスル
Tires(s) タイヤ
Wheel(s) ホイール (or ホイル)
Decal デカル (or デカール)
Body ボディ
Motor  モータ
Motor Mount モーターマウント
Works ワークス
Vintage  ヴィンテージ (or ビンテージ)
Chassis シャーシ

AYK あおやぎ
Kyosho 京商
Tamiya タミヤ

and you can use Wikipedia for this purpose
let’s see an example
https://en.wikipedia.org/wiki/Tire
see Languages menu at the left bottom. you can see Japanese as well

RC10 ’94 Worlds Japanese version – 1994

RC10 Graphite Team Car – 1990

RC10 Team Car – 1990

RC10 CE – 1992 version

keep them running!

UK company JC Racing Products (http://www.jcracingproducts.co.uk/) makes 2.2″ wheels for Yokomo wheel hub. and they sell them on ebay
http://stores.ebay.co.uk/jcracingproducts1989
KEIL sold the wheels with his brand name at 90’s as far as I remember

I just got white and fluorescent yellow dish wheels from them. I’m not sure when I can go to the track with the wheels. winter is cold here. and the indoor circuit in my town closed forever. here are some pics

Yokomo 2.2″ wheels have raised 8 ribs inside. and JC wheels got only 5 ones which are almost flat and thicker

the wheels were sold under KEIL brand at 90’s. and I think that means the wheels are strong enough. actually they are softer then Yokomo’s and don’t seem to be broken

the edges need to be trimmed before gluing

I went back to older ’94 chassis from ’95 Worlds Spec (Pavidis edition). ’cause the original chassis looked better for Lipo setup. and it is

’95 chassis is still great for looking and was for running. but   we don’t need the weight saving holes anymore with Lipo setup. even the chassis is not strong enough for Lipo + brushless

older epoxy topdeck always worked for me. so, I went back to it

YZ-10 with Lipo seup

 

 

 

from left to right RC10 dogbone axle, RC10 universal, and B2/B3 universal

RC10 CVD – 1/4″ axles stock #6366 (#6365) hub carrier with 1/4″ x 3/8″ flanged bearings

there are not much options left with stock 1/4″ axle. they would be Yokomo TH-1 with deep offset wheels

or, hex adapters from a few manufacturers like HPI

stock 1/4″ axle with HPI hex adapter #7365 (#7358) hub carrier with 3/16″ x 3/8″ bearings

stock 1/4″ axle with Yokomo TH-1 adapter

Hong Nor (OFNA) TM-49Y yellow (white is TM-49W)

ZC-835 wheels with Suzuki wheel hubs

ZC-835 wheels with TH-1

and the original setup

 

 

#2 with 3/16″ B2/B3 or B4 axles

there are a few knows tips like this one from rc10talk. and you can find more from the forum. it’s a great site for you and your cars both

http://www.rc10talk.com/viewtopic.php?f=38&t=8848

RC10(B2/B3) CVD bones with B4 3/16″ axle and spacer

I prefer B4 axles than older B2/B3’s. this setup provides more wheels that I can use. even I’m using Yokomo TH-1 with a simple trick

both axles were made for 8-32 locknut. but the diameters of the selected area are different

so TH-1 doesn’t fit the axle

enlarge the hole with step bit or 3/16″ drill bit.
I tried step bit and the result is pretty good. but I think 4 to 5mm trimming from the inside with 3/16″ drill bit will give the perfect result just like they came from the factory

then this adapter fits old 1/4″ and newer 3/16″ axles both. actually I did this job a year ago. and still use them on my runners.

I like this mod ’cause it’s still easy to get TH-1 wheel hubs. and RPM ’91 RC10 doesn’t need the deep offset wheels. the ’91 RC10 in the picture are the same car. I’m using ZC-837 non offset wheels and B4 wheels with it. this RC10 is sharing the pink wheels with YZ-10

 

it works with Associated

#3949, #3950, #3972, #3973, #31032 hex wheel adapters. and with hex type wheels as well.

’91 RPM RC10 and modified ’94 Worlds

gold anodized ’94 Worlds with ZC-835 wheels

 

and check the parts from HPI

 

 

I posted this on rc10talk forum when I started to build this. it took more than a year just for collecting the parts. and I spent another year for restoring itself

it was bought from Taiwan at 2007 maybe 2006. I noticed there were only few parts that I could use for my project. it came with broken gear box, missing or wrong dog bones, crushed and damaged axles. broken steering knuckles and more.

I still have the picture of the parts. every single axle was crushed like this diff out drive

this picture was taken during the restore. I put early chassis and RPS roll bar on my resto. most of the parts I built with were new. and I got tons of garbage. it was like a blues song. I’ll give this story to Elmore James if I meet him in another life

it took 2 years to the 1st run

Novak T-1X was crazy powerful

and got this after I spent another hundreds dollars

YZ-834B Wonder Dog Fighter with ’83 body

A friend made me new motor plate. the original one is too weak. even can be bent easily with bare hands. he made 20 maybe 30 pieces and still sells them on ebay. not much left now. so hurry up
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=140358612413

I tried a few different color on the motor plate. red is my favorite

I wanted to try the box art aluminum arms. and he did it for me. they look great and provide better handling on the track

mostly from rc10talk.com

already posted this in Korean(한글) on my another blog which I’m building over the last couple of days. and I’m doing this again. I noticed I forgot to put Custom Works wheels in this picture. but I still like this yellow, white, and pinky picture

the original 1.75″ wheels are yellow and very cool. but they don’t showed up anymore on ebay. 870C wheels are 2.0″ and can be replaced with.
and, there are few ebay sellers and online hobby shops sell 2.0″ tires

Losi Rear 2.0 Step-Pin, Silver (2) LOSA7378S

Tamiya #53059 Wide Stud Spike Tires

Tamiya wide stud tires work with  870C front and rear wheels both. so it’s not a problem if you only have the front or rear

870C wheels are deep dish. and the offset is identical to the original yellow wheels

Front narrow ZC-800
Front wide ZC-801
Rear ZC-805

Yokomo TR-8 was stock rear tires for 870C

Front TF-8 (S, M, H compound)
Rear TR-8

834B still runs great with 2.2″ wheels and modern tires. rc10talk forum member kustomizerz made this video
http://www.youtube.com/watch?v=syut2MqNoRc
and his chassis are here
http://www.rc10talk.com/viewtopic.php?f=29&t=6509&start=8
http://www.rc10talk.com/viewtopic.php?f=29&t=1745&start=24

there were a few kind of 2.15″ wheels. ZC-821 front, ZC-822 9mm deep dish front, ZC-825 deep dish rear, ZC-827 with (almost) flat dish
ebay is the best source for the wheels. 2.15″ ROAR wheels work with modern tires as well.

2.2″ 30 series wheels ZC-83x

maybe you can find ZC-837 or ZC-837W 30 series wheels. but they don’t have negative offset. you need to modify the rear wheel hubs if you want to use ZC-827 or ZC-837 wheels
2.2″ (30 series) Wheels

Front ZC-821

Rear ZC-825 (deep dish)

ZC-822 2.15″ 9mm deep front wheels (center) it’s perfect for 834B and 870C but really hard to find

a frankenstein with tamiya arm. during leftover build

#1 front wheel hubs
there are 2 reasons to write on the wheel hubs. the 1st one is they are hard to find. and the other one is for the case you want to run your Wonder Doggie with modern tires. we still have the problem with getting 2.2″ wheels. but let’s get started this topic with ignoring the wheel issue

she, the shop owner still has tons of 834B parts. but I didn’t see the left side of the front oneway wheel hubs for years
http://stores.ebay.fr/Antonias-RC-Buggy-Parts-of-the-80th/Dog-Fighter-/_i.html?rt=nc&_fsub=1849385018&_sid=55350118&_trksid=p4634.c0.m14.l1513&_pgn=1

so, I bought 2 right ones. and tried to pull the oneway bearing out. then put it back. it was quite easy to do with a hammer and 2 thick books. I got a complete pair now

The original yellow and 870C wheels had deep offset. but later 2.2″ wheels don’t. I tried to exchanged the right and left wheel hubs. and it worked. but wanted better solution to hold the wheels securely

the wheel hubs for RC10 and kyosho seemed to be worked.
but, I didn’t try kyosho’s.

got this after the step bit job with RC10 wheel hub. I didn’t cut the back end. and didn’t have to. it has gone

it fits like it was made for this

before

and after

#2 rear wheel hubs
it’s more simple than the front. the hub was from 870C front

now my 834B got right thread and look
and you can see the steering from later Yokomo cars. they are basically same. but work better and easier to find

Yokomo YZ-834B came with few weak spots like most 80’s RC vehicles had some.I have made the list on wikipedia before. pleas check this http://en.wikipedia.org/wiki/Yokomo_YZ-834B and want to add some pics for someone who still runs this old and nice buggy

hotdog4’s rear axle could be a good replacement. I’v been using them for years. and I noticed they won’t ever be broken or crushed

the dogbones were from AYK Race Prep. it’s hard to find now. but it worths to get and run with them

the length of RC10 and 834B front dog bones are identical. but the diameter of the pins are not. you may use RC10’s if you can’t find the orginal or AYK’s. but you need to trim the pins. maybe the heads as well

Yz-834b stock front axles

hardened front axles came with later 834B’s and RPS SE

stock front axles were not strong neither. it had poor resistance to abrasion. the oneway bearing made worn it out like the alxes in the picture

Later Wonder Dog and RPS SE came with stronger hardwares include this axle
I pulled this off my runner which has been racing  for years. it still looks like new