Fighting Buggy turning range

[Lhodgo]

Any tips on improving the turning circle of a new built Fighting Buggy. It currently has the turning circle of a bus and makes it garbage to drive. Have I missed something? Can it be adjusted?

[Fuijo]

Well, it's a dune buggy. So if on sand, give it more power to make it slide.

If on a high grip surface, then fit a ball-diff. But it's not really for high-grip surfaces.

[Terz1]

I love how you described that Lhodgo  .

[Saito2]

For being Tamiya's "competition" version of the SRB, I was always surprised it didn't have a diff which was becoming more commonplace by that time. Anyway, the buggy does indeed steer like a super tanker. No diff plus a lot of the weight on the rear equal loads of understeer. A diff (more than likely a ball-type) will help for sure. One must be careful when trying to physically get more steering angle out of the front linkage. Go too far, and the inboard steering upright will over-center and effectively jamb the wheel. One thing I've found that helps is matching the rear tires to the surface. The stock pin spikes work on looser surfaces. They grip enough to keep the heavy rearend from completely washing out. On higher bite surfaces, its understeer-city, with pin spikes however. I like Sand Scorcher/Grasshopper sand paddle tires on higher bite areas like grass. They offer little lateral grip, so the rear end can "come around more" in a turn, aiding steering. For all-out performance, which is likely beyond the scope of this question, some more radical changes must be implemented. The cool floating rear suspension would have to go and there would be much drilling/hacking of the heavy diff casing to get as much weigh off the rear in an attempt to more balance the buggy.

[Lhodgo]

Thanks Saito2 it sounds as though a trip to the beach may be a simpler solution!  your knowledge is priceless thanks!

[mongoose1983]

13 hours ago, Saito2 said:

For being Tamiya's "competition" version of the SRB, I was always surprised it didn't have a diff which was becoming more commonplace by that time. [...]

As far as I understand, when the Super Champ was released in 1982 differentials were yet to be developed for off-road duties. I'm positive Kyosho buggies did not have them either, and I doubt the AYK 566B had one.

[Saito2]

I'm pretty sure the aftermarket had developed ball and gear diffs for the SRB platform by '82. The Wild Willy came out around '82 and had a diff as did the Marui Land Cruiser and CJ7. The Frog had a diff the next year. I just felt the benefits of a diff in competition were becoming apparent by that time, although this is strictly my opinion as I have no knowledge of what was going on behind the scenes development-wise.

[Mokei Kagaku]

On 10.9.2016 at 6:57 AM, mongoose1983 said:

As far as I understand, when the Super Champ was released in 1982 differentials were yet to be developed for off-road duties. I'm positive Kyosho buggies did not have them either, and I doubt the AYK 566B had one.

You definitely have a point, but there are several reasons why one might think that Tamiya should have included a diff:

1. An optional diff was available for the Kyosho Circuit 20 and though I'm not 100% sure, I think the optional diff for the Scorpion series was available before the release of the Super Champ too. It was at least available before the release of the Tomahawk.

2. The Kyosho Tomahawk is a competition buggy of the same "generation" as the Super Champ, and came with a diff.

3. In organized buggy racing, most acknowledged that a diff was a benefit or even needed at the time the Super Champ was released. After all, it had been available from CRP, Thorp and others for quite some time by then, and hardly anyone who seriously raced an SRB or Scorpion in the Modified class would consider running without a diff.

5. The Wild Willy was released at almost exactly the same time as the Super Champ (the first shipments of SC and WW arrived together at the Tamiya distributor I worked for). And why did Tamiya think an "unserious" stunt/wheelie/fun-model like the Wild Willy should have a diff if they thought the Super Champ didn't need one? Personally, I think it's reasonable to believe that Tamiya at that time knew perfectly well that the Super Champ should have had a diff, but dropped it for cost reasons and/or because of the time required to develop a durable diff that small (not easy in the early 80s) and didn't want to wait that long to get the Super Champ on the market. The buggy market was extremely volatile at that time, so even 3-6 months delay would most likely have made the Super Champ virtually unsaleable for its intended use as a competition buggy.

To be fair to Tamiya, it can be argued that 1982/1983 was the breaking point for diff in buggies though. Released a little earlier, nobody would have questioned the lack of a diff. Released a little later, everybody would have shook their heads in disbelief for the very same reason.

 

[Shodog]

I've ran my rough rider in stock form and with a diff. Ultimately I went with the stock spool. 

[Raman36]

I have the solid axle in both my SS and RR / Buggy Champ.  Both my cars have the Hop up servo saver from the Super Champ / Fighting Buggy, which improves steering efficiency but not the turning radius.

The "fix" was adding an extensions piece which moves the left and right turnbuckles further  back eg straightens them with respect to steering knuckle.  

This alone will improve your steering radius drastically, even with the solid axle. 

The parts I used to achieve this were plastic bits in my tool box. I had intended to make a more permanent fix but never got around to it. 

 

 

[oz-trash-cowboy]

the simplest fix for large turning circle is to run it in a less space challenged area

[Country Mike]

Google ackerman steering and I think you could achieve it.

[ruebiracer]

On 27.10.2016 at 0:55 AM, Raman36 said:

I have the solid axle in both my SS and RR / Buggy Champ.  Both my cars have the Hop up servo saver from the Super Champ / Fighting Buggy, which improves steering efficiency but not the turning radius.

The "fix" was adding an extensions piece which moves the left and right turnbuckles further  back eg straightens them with respect to steering knuckle.  

This alone will improve your steering radius drastically, even with the solid axle. 

The parts I used to achieve this were plastic bits in my tool box. I had intended to make a more permanent fix but never got around to it. 

 

 

Really like your upgrade Raman!

I also bought an Fighting buggy servo saver to upgrade my Scorcher. What I´d like to know is how you build the long body post:

Turning down the original SS part, or build a extension for the short body post of the fighting buggy?

I´m still wondering, what would be the better solution!?

 

[Raman36]

I had a friend who is a machinist make my  a long post for the SS and a short post for the BC/RR.

 

Im guessing turning it down would probably be easier?

[moffman]

Like most of the other guy's have said ball diff is the way to go!, I to built my fighting buggy then took it in the garden for its maiden run and was shocked on its turning circle (the ferry I was on last month had a sharper turning circle than my fighting buggy!) And the train i was on this morning! I put the ball diff in it and although it was no mini cooper it was a 1000% better with the diff in it!

[Raman36]

23 hours ago, moffman said:

Like most of the other guy's have said ball diff is the way to go!, I to built my fighting buggy then took it in the garden for its maiden run and was shocked on its turning circle (the ferry I was on last month had a sharper turning circle than my fighting buggy!) And the train i was on this morning! I put the ball diff in it and although it was no mini cooper it was a 1000% better with the diff in it!

Before doing this mod I tested the car with solid axle and ball diff. The steering improved but not dramatically.

The simple mod I listed above improves the steering radius much more than the ball diff.

Observe the steering angles with stock kit linkage and you will see that the inner wheel is not turning enough.

[moffman]

15 minutes ago, Raman36 said:

Before doing this mod I tested the car with solid axle and ball diff. The steering improved but not dramatically.

The simple mod I listed above improves the steering radius much more than the ball diff.

Observe the steering angles with stock kit linkage and you will see that the inner wheel is not turning enough.

The thing with the ball diff is it makes it much more stable when you corner the solid axle has the tendency to flip it over and if there is one thing you don't want to do with the fighting buggy is flipping it on its roof because as we all know it's got to be one of the most fragile bodies together with the 959 that Tamya make! so surely if the mod you suggest to do for sharper radius do improve it the ball diff would be even more important to calm the back end down?

[Raman36]

I don't doubt your claim about the benefits of a diff vs spool. When I race my 419, I keep 4 spare diffs in my spares with different viscosity to tune for turning

[moffman]

10 hours ago, Raman36 said:

I don't doubt your claim about the benefits of a diff vs spool. When I race my 419, I keep 4 spare diffs in my spares with different viscosity to tune for turning

I think if anybody wants to race a fighting buggy (would be so cool to watch a load of them racing together!) forget about turning radius or ball diffs its spare bodies ya gona need the paper kitchen towels I've just got from tesco's has more strength in it that a FB body!

[ruebiracer]

On 17.11.2016 at 11:13 PM, Raman36 said:

I had a friend who is a machinist make my  a long post for the SS and a short post for the BC/RR.

 

Im guessing turning it down would probably be easier?

Thank you Raman!

Good to have a friend with machines!

I guess I´ll go the way you said and turn down my SS body post.

Your way seems only logical to me, as the Fighting buggy servo saver lever is shorter than the original SS saver lever.

So the steering angle of the wheels decreases. At least you need original SS geometry in my opinion, otherwise you cannot make tighter turns...

 

Br,

Matthias