Yokomo Superhot Dog Fighter

[GrePo]

It has a tradition at Yokomo, releasing Buggy versions based on on-road chassis: 1995 Hot Dog 4 based on YR-4 chassis. And in 1999, when the MR4-BC was introduced on MR4-touring car platform. But inbetween these both there appeared a few YR4-II touring car models without any Buggy derivative. The YR-4 K2 (1996) is one of these. It used a light, super flexible chassis. Maybe they judged this Chassis is not robust enough for Offroad usage.

[GrePo]

But a Buggy conversion for mild offraod use may be interesting because it already comes with a Lipo compatible battery holder and I like the unique shape of the chassis plate and the look of these open bulkhead caps front and rear. I'm curious how good YR- and YZ-parts do fit together. After I checked my spare parts of the 870c/Works/YZ-10 era 1987-1996 I judged there hopefully will be enough bricks to give it a try, building a Buggy starting with these YR parts carriers.

[GrePo]

The YR-K2 chassis is a few millimeters shorter than the YZ/Works. To stretch wheelbase I plan to turn the front arms around. My favourite arms would be the Works´ ones but I don´t have any spares. So my only option was to order a set of 870c re-re arms. Luckily I have a set of old 870c drive shafts.
A challenging step was to find the best-fit position for body and undertray. Moving it more frontal ensures that the open bulkhead is covered completely and at the backend I need to cut the body only a very little bit to avoid collision with rear shock tower. But this is not so good for motor package situation. This body leaves not much room for motor, especially when motor is max. setted back like here because I try to use the optional Yokomo 2-speed gears. I bought one years ago and never had a usecase for it. Fitting it here in is a big motivation for that build.

[GrePo]

My desired equipment is a Novak Hammer fresh rewired with Reedy Tri Sonic. Unfortunalely the Yokomo/Reedy endbell is bending the body away a little. That would let the cutout for the upper deck move off-center. To avoid this, I changed to a motor with a slim endbell. The Orion V2 series fits without stress to the body especially when wired at the bottom side.

[GrePo]

Rear shock tower is from Works'93. Works aluminum bulkheads increased rigidity of the whole car. The upper deck originally is fixed at the back by splint and is positioned so high, there is some space between deck and motor mount cover. This makes the touring car chassis very wobbly. I was forced to lower the upper deck some millimeters to make it fit underneath rear shock tower. I changed back fixation from splinting to screwing and glued it with double-sided tape onto motor mount cover. By the way this modification improved the cars' rigidity very noticeable.

[GrePo]

Moving rear battery holder towards front freed space for second gear lane. In this step I gave up usabilty of NiCad batteries, but since I overcome fear of LiPo batteries, that is fine for me. Chassis includes an "outsourced" hole for servo mount. I had to cut away this section because it collided with the undertray. I will attach servo with hot melt glue.

[GrePo]

Now going to the frontend. 870c arms will fit only with 870c C-hubs. I combine them with YR4 steering blocks. Don't want to buy 870c steering blocks because these use specific bearings and I want to go as much as possible with available parts. YR4 steering blocks are much different in detail. Hight must be reduced -3mm and the distance between both bearings is larger compared to Buggy about 2mm I guess. So the milled flatten surface on driveshaft must be extended to come together with grub screw inside wheel adapter.

Don't know the source of this shock tower. It is different to Works 91 and 93.

The driveshafts are angled forward so much, that the c-hubs inner edge needs a little chamfering.

[GrePo]

Of these nice, 14mm long M3 threaded studs, there are laying 3 pieces in my screwbox since 20 years, when I collected them within debris after a highspeed crash in 1/8 track race. They appear like ttanium or platinum. Now 2 of them getting a new task. They help installing front shocks behind the tower.

[GrePo]

...stunning studs...

[RogueIV]

FanRC makes replica works arms if that's what you're looking for

[GrePo]

Good point, but I´m happy with what it is now. Going on adapting the body.

[GrePo]

Different but unmistakable the same DNA: Superdogfighters 1987-1996

[Frankentruck]

Awesome buggy! The name really makes me chuckle. A extra space and it because Super Hot Dog Fighter! The Kobayashi of RCs!

[GrePo]

Only problem is I cannot extract capital letter H from the original lettering. Maybe this is the right name

[GrePo]

In the meantime I installed electronics and moved the dampers infront the tower for a more common overall look. Did a first shakedown run today but very short because the radio suffers from interferences. It is an AM receiver, maybe I have to check a better antenna cable routing. I hope it is not a general problem when AM receivers are placed derectly beside esc.