Kyosho Scorpion 4x4 build project

[Dadio]

I got started on the steering system , there are a few areas that need attention as yet , i have a slight binding issue on the track rod ends with suspension compressed but i have a couple of ideas to overcome it , clearance is tight as the links go under the diff out drive cups and there's only 3mm so they are just over 2.5mm thick , bump steer is acceptable and probably less than stock , its not clear in the pictures I'm afraid , the top part of the top crank for the linkage is over size at the moment as i was not sure of the relative alignment of the top and bottom arms as its not 90 degrees so i thought I'd fit it and then mark the position for cutting later .
the really good news is that it all fits under the body.

[Gayo]

Fantastic!!

[Dadio]

She went for a brief test run this evening , there are two little issues .
1 it has the turning circle of an ocean liner .
2 There is a little clearance issue with the chain .
I was kind of expecting the poor turning circle and have a cure , I'm going to drill and tap the steering hubs so i can fit the ball studs for the track rods closer in ,this will increase the turning angle ,probably increase it too much but i can reduce it by end point adjustment.
The chain clearance will be easy ,either adjustment or removing a little material .
This sounds bad but this is the kind of stuff you have to expect in a project like this , I'm actually pretty chuffed that it worked as well as it did first time out .

[Dadio]

After adjusting the steering linkages i got a chance for a road test this evening , on the road it's a little low on straight line stability but i think that's largley down to tyre choice , there's no understeer anymore , in the short grass of my front garden it was really transformed , tracked nice and straight and turned nicely .
The only thing that surprised me was that it still pops wheelies even with the extra weight on the front axle .
I still have to make a chain tensioner as there's a little slack that makes it a little noisy but other than and a little finishing off of some parts and some paint then she's finished .

[Dadio]

The cvd shafts arrived today and they fit the steering hub well but are slightly too long and the pin in the dog bone end is too wide , i have a set of Scorpion dog bones coming so it's a simple matter of cutting and joining the two shafts at the right length .
After that then all that's left is a chain tensioner and paint yay !
Oops i missed an update on this forum , I've been having issues with the front dog bones popping out so i decided to use cvd shafts instead , i know they are out of period for this build but they have they have virtually no visual impact and they solve a problem that was a curse on all 4x4 cars of the 1980s , my Hot Shot was forever dropping front shafts and I'd have given a pretty penny for cvd shafts back then .

[Dadio]

The scorpion dog bones arrived today and I found a little time to make sleeves and cut and silver solder the two parts together but by the time I was finished it was 10.15pm , where does the time go ! So it's road test in the morning yay !!!

[Dadio]

Well the test drive went perfectly , it even withstood a cartwheeling crash ! I'm not even sure i need a chain tensioner yet ,probably will as the chain stretches but not yet .
only downer is with Photobucket being too glitchy to work right now so i still can't give any photo updates , i'll try later , i'll see if i can persuade someone to help video it in action as well .

[Dadio]

photo update showing cvd shafts and wheels , im more happy with the silver soldering on the shafts and i made the sleeves slimmer as well so they look neater at least to me .

[Dadio]

Painting went well and I've given the chassis and wheels a scrub , I'm just waiting on a new set of decals and I'll get some finishing photo's before she gets all grubby and scratched up , after the photo session it's gloves off and a video of her getting some proper rough and dirty driving .

[OptimaFan]

Looks nice, just wondering if the drive shafts won't start chattering when you steer the wheels, because these are already at an angle with the wheels neutral.

[Dadio]

Originally Posted by OptimaFan

Looks nice, just wondering if the drive shafts won't start chattering when you steer the wheels, because these are already at an angle with the wheels neutral.

I've try'd to keep the end points limited to keep within the limits of the cvj's but to be honest it's not too much of a problem as there's more usable articulation than the dog bones before they fell out , the shafts are swept forward from diff to wheel at full suspension extension and swept back slightly at full compression , this gave me all sorts of problems with the dog bones and trying to get end float and no binding , I really didn't want to use cvj's as they are too modern but they have solved the problem .

[Dadio]

A few finished pictures , video soon.

[Dadio]

Well i made a short video with the help of a friend but its not great quality , its a stills digi camera taking video , i have now got trouble with the chain tension so i need to make a tensioner , i guess as the chain has run in and stretched a little . Anyway it was no surprise and i always expected to need a tensioner
https://youtu.be/8Zch4oMkta4

[Dadio]

New ESC fitted and tested and running well , it's just a hobby king 120amp x car ESC but it's all I need .
I also cut a little more out of the tub where the chain was touching so I then finally got to re test it and it's all working well yay !