MT4 G3 / ST1 Pro Bash Truggy conversion

[Lizard]

1/8 scale tires only last 10-20 packs for me, so got myself some 1/5 scale tires.


1) From a Carson Dirtattack 1/5 scale buggy.
They are already glued and with 280g reasably lightweight. Foams are soft enough for the 5-6Kg of an 1/8 scale car. Diameter is a little bigger than Maxx size but smaller than HPI GT2 tires, I really like it that way. What's not so nice is, that they have very little offset, so I needed wider squares. Took 17mm wide ones, vehicle width seems okay now. They seem quite sturdy, rubber is thicker also. I hope they'll hold up better than 1/8 tires that I always shred within 10 to 20 packs or so.

2) Carson FG wheels and FG Marder Buggy tires. Problem with them is, that the foam is too hard for 1/8 scale vehicles, but I have already ordered some softer ones. I also decided to turn down the part of the wheel where the tires are glued to (see pictures) because with softer foams I think the tire would "bottom out", not good. With FG foams and turned down wheels they only weigh 250gram now, nice.

3) PMT Supreme V2 touringcar onroad tires. Very good traction (wheelies with those small tires, yeah) but foams are a little to hard for 1/8 scale weight, I think I need to get some unglued ones and replace foams.


Center diff is still the Savage Nova diff, but with 2.000.000 cst Oil in it. I am almost not able to turn the diff by hand now :). If I grab the car by the rear wheels and push it over the ground with the front wheels the tires will skid, only if I press the car to the ground in a 45 degree angle the tires will move.
Driving was very good, all 4 tires now always have the same diameter, no front-balooning anymore. In general the tires baloon only very little. Interestingly, the center diff still got quite warm (but not hot anymore) so it's still doing it's job of protecting the drivetrain, very good.

Gearing was changed to 18/46, that's 97km/h with the Carson tires. Also fitted a small 50mm fan on the motor, temps are much better now, after running two packs, max temp was 47C, but most of the time it stayed around 37C. Ambient temp 20C.
But I must say, it feels a little slow now, it stops doing wheelis at about (estimated) 60-70km/h now, with the old gearing (108km/h) it would still do them at 80-90 estimated. Now it's somehow missing that nice "there's still plenty of oomph left" feeling at high speeds.

Seems like I have to improve motor cooling, so that I can run higher gearing again. Unfortunately I couldn't find a motormount that has good heat transfer to the chassis, seems like most manufacturers don't use their brain when designing motor mounts :(

[Lizard]

more pictures:

[Lizard]

Finally had the time and opportunity to make some videos. Sorry, they are a bit shaky.
I guess I smoked that guy with his yellow FG Monster Truck pretty good

Gearing was 20/46, topspeed 66mph measured with GPS "Android Tacho" app.


Offroad:
http://youtu.be/oJ4qirFzCLM

Onroad:
http://youtu.be/Gpb5UubZMMI

[SpeedAssault]

Originally Posted by Lizard

more pictures:

Very cool
Where can I pick up these stub axles?
I made my own Square hubs from Delrin and turned down losi bolts to adapt traxles outer stubs to FG wheels.

Thanks

[ruudxd]

Looks like they are the stock 8 mm stub axles with flats ground on them to accept the grub screws is the hubs.
That should be quite easy to do on any 8mm stub axle I think?

[SpeedAssault]

Originally Posted by ruudxd

Looks like they are the stock 8 mm stub axles with flats ground on them to accept the grub screws is the hubs.
That should be quite easy to do on any 8mm stub axle I think?

Stock what?

this is a hybrid, right?

Coming up Blank on mt4 stub axle, or 8mm stub axle, thundertiger stub axle.

Pictures are nice to look at, but dont know where part came from..??

[ruudxd]

As far as I can see in the exploded views, both the MT4 and the ST1 came stoch with 8mm stub axles, like almost every 1:8th scale car I know of.
In the pictures I see a standard sub axle with some flat spots ground on them, done by the owner.
The MT4 comes with these axles, not in stock, but you should get the idea:

http://www.dollarhobbyz.com/collecti...shaft-assembly

The FG square hubs are like these, the part number depends on the width of the hub:

https://rc-car-online.de/en/products...5mm-steel.html

The other pieces look the be just a peace of brass pipe, with a ID of 8mm, and a bolt that fits in the axle, you should be able to get that in your local hardware store, or at a machine shop?

I think I am misunderstanding you, my English is not that good, sorry.