Steering modification of Mugen Bulldog
Posted: Sun Mar 22, 2009 10:45 am
I found the Mugen bulldog has terrible steering. 
The original 4wds was a terrible idea with tons of oversteer and the plastic was too sloppy and resulted in no accuracy even to run straight. That was my memory in 1985. Back then I locked out the rear steering, modified the front using the original dual bellcrank set up but the amount of steering was very limited, hotshots literally ran circles around my bulldog in half the radius of the bulldog....
This time I change the setup a bit: direct steering like a 1/12 scale, well almost. I know this will cause a lot of bump steering but what the heck, it is fast, accurate, direct and most importantly, I would never run this car off-road anyway!
I chose tamiya F103 turnbuckles for the rear, which makes it very easy to change the toe-in. Front end, being a little odd in the tie rod length, I just get whatever it is available in my tool box.
I made some graphite brace for the anti-roll bars to stiffen them up, I grease the sway bars and shrink wrap the bars because they rust like anything without the grease and they are never shiny.
Also got a Kimborough servo saver and added a graphite extension. Take a look at the bulldog steering hub and you would notice the arms was about 45 degree from the car's long axis and therefore there is a need to make the servo saver at a 45 degree to make use of the geometry and maximise its steering angles.
With all these work, after almost 4 years sort of R&D, I would say, I am reasonable happy with the results.
The original 4wds was a terrible idea with tons of oversteer and the plastic was too sloppy and resulted in no accuracy even to run straight. That was my memory in 1985. Back then I locked out the rear steering, modified the front using the original dual bellcrank set up but the amount of steering was very limited, hotshots literally ran circles around my bulldog in half the radius of the bulldog....
This time I change the setup a bit: direct steering like a 1/12 scale, well almost. I know this will cause a lot of bump steering but what the heck, it is fast, accurate, direct and most importantly, I would never run this car off-road anyway!
I chose tamiya F103 turnbuckles for the rear, which makes it very easy to change the toe-in. Front end, being a little odd in the tie rod length, I just get whatever it is available in my tool box.
I made some graphite brace for the anti-roll bars to stiffen them up, I grease the sway bars and shrink wrap the bars because they rust like anything without the grease and they are never shiny.
Also got a Kimborough servo saver and added a graphite extension. Take a look at the bulldog steering hub and you would notice the arms was about 45 degree from the car's long axis and therefore there is a need to make the servo saver at a 45 degree to make use of the geometry and maximise its steering angles.
With all these work, after almost 4 years sort of R&D, I would say, I am reasonable happy with the results.
