bcpzx3

iTrader: (1)

undo the servo and move the wheels left to right by hand. See if it can move both ways freely. If so, your servo probably has a broken tooth.

kaboomwoom

i found this link very helpful for rc18 tuning/upgrades world wide web dot competitionx dot com/rc-support/rc18-series/

kmas

iTrader: (72)

I parted out my rc18t stuff, here is what is left if anyone wants a cherry exotek roller.

http://www.rctech.net/forum/r-c-item...r-package.html

vw addict

iTrader: (38)

I want to know if those GT-Z bodies on ebay will fit an RC18LM. It says 18R, will it fit the longer chassis too?

trdsupra88

iTrader: (25)

Yes it will, you must find your own way to cut the wheel wells but it fits perfect... I lined the front wheels with the marks then eyeballed the rear...

vw addict

iTrader: (38)

awesome, you didn't just mark everything before you painted?

65BAJA

I ended up putting the CM20/6800kv motor back in . The CM26/4600 was just too much.

The steering is way better with the new centerlink. I may end up carving a little bit out of the diff case to get better steering though. The ball cup bottoms out against the housing.

alanmeyer

iTrader: (16)

I have an RC18b that has a steering problem where it will go straight and then turn a bit so that I'm constantly providing steering input.

I went thru the process of buying a new stock servo saver kit and I added a spring to make it stronger (used a stock shock spring, recommended by my LHS). However, the problem is still basically the same.



My question is: Could this type of steering symptom be due to my front or rear diffs needing to be rebuilt? I have an RC18t that has even more play in the steering than my RC18b, but doesn't exhibit the steering problems.

What are some other items to look for?

derelicte

iTrader: (1)

I have this same problem and it is driving my crazy. I'm not sure how much material you can remove from the diff housing so I'm thinking of making little brackets that attach to the steering links that move the ballstuds further out.

If I succeed, I'll post the results.

derelicte

iTrader: (1)

I have the same setup with the cut shock section around my servo saver. One thing I read about this setup is the spring is lower than the bottom of the servo and rubs against the chassis so you need to either raise the servo or grind out a little of the chassis for clearance.

you could also have a bad servo. does the servo center correctly if you remove it from the car and try it on the bench?

alanmeyer

iTrader: (16)

I've also noticed that the spring/saver rubs on the bottom like you've pointed out. However, it's minimal because the wheels return to center 1000 times better than it was before I installed it. This is something that I will fix, though. Probably with some tape under the servo to space it up.

I've placed the servo on the table and observed its behavior. I've also simply removed the turnbuckles with the servo still mounted in the chassis and watched the arm return. I think that the only way for me to eliminate that as a problem, though is to swap the servo and see if the problem persists. I will be able to do that since I have 2 of these cars. I just haven't tried that yet.

It just seems odd that I have another RC18t that has a lot more play/slop in the steering yet doesn't exhibit this symptom. I've even swapped the tires.

Another difference is that I have a CM2080 motor, which exacerbates the steering problem. I'm not convinced that it's the motor, though. That's because the symptom occurs even at lower speed.

The main reason that I suspect the diff is that if the internal resistance is somehow uneven, that it could be causing some type of torque steer. My next experiment is to remove the front dog bones and see if the straight-line movement improves.

derelicte

iTrader: (1)

I pulled my servo off this afternoon and found a groove worn in the chassis where the cut spring section is, so I dremeled out the chassis to provide some clearance.

This made a huge improvement!

Before, I was never really able to move the servo by hand if I turned the front wheels. It just kind of torqued the servo saver a bit.

Now when I move the wheels by hand, it actually spins the servo quite easily.

I haven't run the car yet because I'm still in the process of installing a driven productions gear case cover and I seem to have lost the washer for the top motor mount screw.

However I hopeful that this will eliminate my steering centering issues.

Now I just need to see if I can address the poor turning radius caused by the ball cups hitting the diff case.

The bottom line is, if you do the spring coil mod you need to either raise the servo or dremel the chassis.

65BAJA

What is this coil spring mod? Pics?

alanmeyer

iTrader: (16)

Look up at my picture just up a few posts (#1868)

derelicte

iTrader: (1)

see here:

servo saver mod



I used a blue spring for mine. I'm not sure it matters all that much what spring you use (silver, bluer or gold). You definitely need to either raise the servo or grind out the chassis for clearance, though.