Sydewynder

Sure I'll run with you guys especially if racenut123 is running , but you said not if I have shuie's livery. Oh well too late.

Need to talk to Steve Wang for some go fast parts.

I still don't like the interference when the wheels are turned and the suspension is compressed. You guys have this problem?

Neil Rabara

What do you mean by interference? Describe what the problem is.

Sydewynder

Neil

When you turn the front wheels al the way to one side then compress the front suspension, the ball cup hits the underside of the front diff case. The suspension doesn't get it's full travel because the diff case wants to push the ball cup back.

psycho

If I don't compress the suspension, I don't have the problem. I don't think you will see that amount of suspension compression on track. Well, maybe if you crash, but you have bigger problems if you crash. Looks like we may be rained out this weekend.

Neil Rabara

There is not much you can do about that. Unless you change the geometry of the suspension, which isn't legal for TCS. For club racing, you may alter the geometry. Are you referring to the inside ball cup of the steering linkage? If so, mine do that.

Sydewynder

Maybe you don't crash but I do.

So no RCCAR fun run?

Sydewynder

Yes this is what I'm referring to. I guess that's the way it's designed. Thanks for confirming Neil.

Neil Rabara

I try to keep the geometry the same on both my carbon car and tcs car. Even though the handling characteristics are different, they drive similar due to the geometry. However, if I were to change something, the first thing I'd do is eliminate the bumpsteer.

psycho

Neil

Here's a question for you. I meant to ask at TCS, but forgot. If I were to use some Tamiya tie-rods and bend them in a manner that eliminates the bumpsteer, would that be legal? Would you mind asking the next time you speak with Fred?

Neil Rabara

Yes it would still be legal because you are using Tamiya parts. However you won't eliminate the bump steer no matter how much or how little you bend the tie rods. The reason for this is due to the locations of where the tie rods are attached. As far as geometry goes, it is the two points of attachment, not the bend or curve of the line that attaches the two points. As a result, the bump steer remains. The only way to remove the bump steer is to change the position of one or both of the attachment points. In this case, the steering linkage. You will have to raise the ball cup on the bell crank side, and/or lower the ball cup on the steering knuckle side. Neither of which is TCS legal. Besides if you raise the ball cup on the bell crank, it will hit the lower gearbox case. If you lower the ball cup on the steering knuckle side, it will hit the lower A-arm. Hope this helps.

TVree

Re: Bumpsteer--

FPM makes tie rods which are bent, and are meant to attach to the same spindle hole as the original ones, but with the ball facing downward. This works in eliminating bump steer, but the rods tend to roll over and rub the lower A-arms if you hit anything ---Neil, you've seen me "drive" :-) ---- and this limits the steering afterward. I'm back to the original setup with straight tie rods.

The FPM rods are not TCS legal, of course; but an interesting experiment to solve the problem!

For So CA racers---we're racing this Tuesday at SoCal again---part of the 2nd and 4th Tuesday group, which grew to 10 racers last time. See you there!

Terry V.

psycho

TVree hit the nail on the head. I have the FPM rods and there is virtually no bumpsteer with them since it allows you to put the ball on the bottom of the knuckle. Since there's nothing explicitly banning this and it doesn't seem to me to be out of the spirit of TCS, I'll make up a set from Tamiya parts and see what they say at tech, I guess.

Neil Rabara

Psycho, the following is rule number 5, 15 and 17 under the "All Vehicles" TCS rules:

5. Any Tamiya Hop-Op Option and spare part is allowed as long as it is used in the way it was designed, and on the vehicle it was designed for. Except for the GT1 class, it is strictly forbidden to cut, mill or lighten the chassis. It is strictly forbidden to re-engineer or modify the cars in any way other than with Tamiya Hop-Ups. (This applies to all classes)

Using say a hopup (steering rod) and bending it would violate this rule.


15. The use of thin shims (available at most hobby stores and now made available by Tamiya) to space out the slop or play in suspension arms, steering bellcranks and wheel axles is now permitted in all vehicles except in the TL-01 spec class. (New as of 2003 season). Shimming the aforementioned components of the car in a way that alters the geometry of the car or its basic design is not legal.

I read this to say that if the geometry is altered it is illegal (steering) because of the placement of the ball end on the knuckle (upside down).

The following is a blurb about loopholes:

17. If a driver finds a loophole within the rules, that exploitation will be deemed illegal.

What I am trying to get at is learn to drive the car with the bumpsteer rather than trying to get around the rules with a loophole by inverting the ball end on the steering knuckles.

psycho

Crap! That happens to me every time I start thinking!

Oh well, the no-bumpsteer rods work well on my cf club racer, so I guess I'll go back to that car.

Neil Rabara

I tried a one way and took out the bump steering in my carbon car tonight. Boy what a difference! It drives very similar to a sedan now. It doesn't corner as fast because of the long wheel base, but still fast enough.