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Having mostly Tamiya and Associated 2wd buggies in my runner stable, I am used to the 10.5-ish wheelbase common in gold tubs and Madcaps. I picked up a Traxxas Bandit awhile back and will probably get into modding it this winter. The first thing that struck me was how long its wheelbase was, like the old limo chassis TRX-1 (somewhere in the realm of 11.25") I'm guessing a longer wheelbase probably adds an understeer-y feel but aids stability. My JRX-Pro has an equally long wheelbase which was stretched over the previous JR-X2 which was more akin to the gold tub RC10. Traxxas went the other way, reducing the TRX-1 wheelbase with the follow-up TRX-3. Interestingly, Kyosho seemed to split the difference with a 11" wheelbase on their Triumph. So what was the purpose of all the wheelbase changing? Why did Losi go longer while Traxxas went shorter? Is there an ideal wheelbase for this style of buggy? I'm making a custom chassis for my Bandit which is what brought these question to mind.

Saito wrote: ↑Sat Nov 13, 2021 12:27 pm Having mostly Tamiya and Associated 2wd buggies in my runner stable, I am used to the 10.5-ish wheelbase common in gold tubs and Madcaps. I picked up a Traxxas Bandit awhile back and will probably get into modding it this winter. The first thing that struck me was how long its wheelbase was, like the old limo chassis TRX-1 (somewhere in the realm of 11.25") I'm guessing a longer wheelbase probably adds an understeer-y feel but aids stability. My JRX-Pro has an equally long wheelbase which was stretched over the previous JR-X2 which was more akin to the gold tub RC10. Traxxas went the other way, reducing the TRX-1 wheelbase with the follow-up TRX-3. Interestingly, Kyosho seemed to split the difference with a 11" wheelbase on their Triumph. So what was the purpose of all the wheelbase changing? Why did Losi go longer while Traxxas went shorter? Is there an ideal wheelbase for this style of buggy? I'm making a custom chassis for my Bandit which is what brought these question to mind.

I would think that top speed and track design would be influences on wheel base. Having a short track, lower speed and lots of twists would be better for a shorter wheel base to improve turning aggressiveness. Go to 1/8Th scale with long tracks, fast top speed and sweeper turns you can run longer chassis.

That's a great question. Why did 1/10-scale cars get significantly larger? Lord knows. They lengthened wheelbases, pushing the wheels farther apart, while widening the track accordingly, pushing the wheels outward as much as possible. Today's 1/10-scale car is way bigger than decades ago. RC cars (buggies, anyway) today look nothing like real buggies. Today's buggies do ridiculous jumps that bear no similarity to real-scale performance...just as RC helicopters do absolutely ridiculous sh!t that no real helicopter could do...because the toys are so much lighter and overpowered relative to their 1:1 counterparts.

Steering performance, understeer/oversteer is affected by so many factors that there's no perfect-for-all recommendation. Weight, weight distribution, wheelbase, track width all play a role, and what works for one chassis will be totally different for another.

The racing rules on size probably led to the size 1/10 cars became but originally they were scale models , all the original Tamiya offerings were anyway so the length and width were just copied not dictated by a set of racing rules.

JosephS wrote: ↑Sat Nov 13, 2021 1:41 pm

Saito wrote: ↑Sat Nov 13, 2021 12:27 pm Having mostly Tamiya and Associated 2wd buggies in my runner stable, I am used to the 10.5-ish wheelbase common in gold tubs and Madcaps. I picked up a Traxxas Bandit awhile back and will probably get into modding it this winter. The first thing that struck me was how long its wheelbase was, like the old limo chassis TRX-1 (somewhere in the realm of 11.25") I'm guessing a longer wheelbase probably adds an understeer-y feel but aids stability. My JRX-Pro has an equally long wheelbase which was stretched over the previous JR-X2 which was more akin to the gold tub RC10. Traxxas went the other way, reducing the TRX-1 wheelbase with the follow-up TRX-3. Interestingly, Kyosho seemed to split the difference with a 11" wheelbase on their Triumph. So what was the purpose of all the wheelbase changing? Why did Losi go longer while Traxxas went shorter? Is there an ideal wheelbase for this style of buggy? I'm making a custom chassis for my Bandit which is what brought these question to mind.

I would think that top speed and track design would be influences on wheel base. Having a short track, lower speed and lots of twists would be better for a shorter wheel base to improve turning aggressiveness. Go to 1/8Th scale with long tracks, fast top speed and sweeper turns you can run longer chassis.

I concur with this assessment. There are wheelbase and track width adjustments on many of the competition grade buggies from bitd. I think it is a combination of track size, surface conditions, driving style, etc.

There was a factory option short wheelbase chassis available for the TRX-1 and also a factory option long wheelbase chassis for the TRX-3/TCP. The TCP specifically also had wide front track width parts in the kit as optional.

I had no idea as a kid about any of the chassis options, even though they were listed right in the parts sheets. Who had the $50+ bucks for that stuff when any benefit other than cool factor would not be noticed by a casual Sunday/club racer. At least that was me. I would definately love to have a SWB TRX-1 and a LWB TRX-3 now but just for the cool factor...

I think Dadio is nail on the head with the rules aspect of todays cars. Push those corners out to clownish "scale" proportions for use on these modern high-grip turf and carpet surfaces, mad air, etc.

Thanks for the insights. In reading, the Bandit seems kind of prone to understeer. I'm thinking of bringing it down to a RC10 length wheelbase.

My brain says shorter arm cars would require a shorter chassis and longer arm cars would require a longer chassis to get the weight transfer balance right.