bellcrank slop

[LazyBoy42]

todays my first day of bashing my 4wd since i have been racing it, i just got my ******* 6.0 25c pack a try with my mmp/ballistic 4.5 and when i turn left, the truck will vere to the left once the tx has returned to neutral, and the same with right. when ou wiggle whe wheels, there is 3/4mm of slop. my turnbuckle rod ends are fine, checked them. any other ideas before i have to pull my undertray?

also what size are belcrank bearings?

[SF1688]

I think the slops seems to be a built-in issue...perhaps to do with the tolerance for the aluminium parts...mine is the same on the UE...

[MVB]

the bellcrank slop is alo my biggest concern with mu slash 4x4.

I just can not gen rid of it.

I have read somewhere that the STRC aluminum bellcrank still has that slop..

[El Sob]

I think just about everyone has that slop. I have it in my right front only.

[Gadgeteer]

yep, the slop is is due to the tie bar that holds the left and right bellcrank together, i think this is to prevent the likelihood of binding(beacuse of dirt) if the tolerance was tighter.

On 8th scale buggies, the tolerance seems to be much tighter, requiring stronger servos for steering....

[sewerdog]

the strc has the same slop, just cant get rid of it . the slop is in the tie bar scews that hold the left and right bellcrank together the right side has more slop than the left on mine too ,guess there is no fix for it ,does make toe adjustments a little harder

[koolkat]

It is not too bad new - gets worse with heavy use with increased play in several places. There are lots of connections between the two wheels:
- wheel to axle x 2
- axle to steering block x 2
- steering block - c-hub x 2
- steering block - turnbuckle x2
- turnbuckle - bell-crank x 2
- bell-crank - link x2

So there are 12 joints that directly affect steering play and all get looser with use. In addition the below 8 also have a small affect in tightness of steering.

and you can add play in bits that also affect steering play:
- a-arms - c-hub x2
- a-arms - skidplate/gearbox/bumper x 2
- upper arms - c-hub x2
- upper arms - shock tower x 2

I bought a rolling chassis basically to use for spare parts for our three trucks. I just compared that to the three trucks that have had lots of use. Just about every single joint is a bit tighter on the rolling chassis - not much at each joint - but add it together and it is really noticeable.

[MVB]

sometimes i just replace most parts just for the better handeling the truck has when parts are new..

just like you say.: not much at each joint - but add it together and it is really noticeable

[sewerdog]

we had a traxxas rep at our track this weekend, he told me it was normal and should have no effect on the truck, thats what he told me ,sooo i guess we have to live with it

[MVB]

no effect on the truck.. wow and a traxxas rep told that?

[FSTR4X4]

no effect? how about shooting left and right on the road because your tires have slop. my 4x4 doesnt see the road because of the slop. my 2wd has slop but since it doesnt have power on those wheels it doesnt do anything crazy.

[revolt0]

Slop is built into most offroad racing vehicles to compensate for minor bumps and things that we run on on a the track. If everything was 100% tight with no slop every little stone, divet, etc would throw the truck all over the place. These are not touring cars that run on perfectly smooth tracks where very tight and percise control is needed and wanted.

[FSTR4X4]

Slop is built into most offroad racing vehicles to compensate for minor bumps and things that we run on on a the track. If everything was 100% tight with no slop every little stone, divet, etc would throw the truck all over the place. These are not touring cars that run on perfectly smooth tracks where very tight and percise control is needed and wanted.

which is why when they're new they dont have any slop and they handle amazing?

the amount of slop I have and every other truck ive seen means the difference between turning left and turning right. so basically the truck will never go straight

[dsiomtw]

I know this is an old thread but I stumbled on it while searching for answers to this same problem. The right definitely has a lot more slop than the left. People talk about the "slayden setup" and other setups which dictate for example 1.5 degrees toe out, but by my untrained eye the slop alone gives +/- 5 degrees of random toe so what is the point of even trying to set it???

[WiNandLeGeNd]

I have noticed this issue and it is a big problem when running a 2.4HP 2400kV on 4S going 57mph! My truck has maybe 30ish runs on it, so there shouldn't be that much wear on the thing. My old school rusty I had when I was a kid had quite a bit less slop that this. The tolerances are just too lose and accumulative effect is rather bad.

I believe there is a multi-step solution though. Try warping tefflon tape around the barrel screws several times until you can just barely shove the barrel screws into the tie bar holes. Even though the fitment will be tight, the tefflon is an excellent friction reducer and will allow relatively free movement due to its lubricating properties. Or you could also find some brass tubing that fits snugly around the barrel screws and drill out the tie bar a bit and use them as bushings (a bit of bushing oil wouldn't hurt), although this would be much more difficult to do with precision, but may provide for the tighest fitment.

Second try replacing the rod ends with the RPM nylon rod ends. To my understanding they have a very snug fit and the nylong is a somewhat self lubricating material and should provide for a tigher fit for a longer time period than the stock composites. I have not tried all of this yet, but will do so soon. I'll try and report back if it all works to reasonably reduce the slop. I think 1 to 2 mm is acceptable, but 3 or 4 mm is not!

[beetroot72]

I added the aluminum bell crank, aluminum carriers, aluminum turnbuckles and a Ace DS1015 servo...make sure the bell crank bearings are in good form as well!

The Servo was the most rewarding upgrade, not necessarily for slop but for ultimate responsiveness!

[JustinThyme]

After replacing all the bearings, aluminum bell crank set installed, all new ends and all joint shimmed even at the hinge pins I do still have a little slop but its very minute, especially compared to what it was with the stock parts right out of the box and its all between the servo horn and the cross link, left and right past the cross link are tight as they get with no play at all. If I set them for a specified toe they stay there. Just takes a little time and a stack of shims going through each and every joint and making them as sung as possible without adding binding.

[Dgb007]

we had a traxxas rep at our track this weekend, he told me it was normal and should have no effect on the truck, thats what he told me ,sooo i guess we have to live with it

Pay no attention to the 900 pound gorilla ,nothing to see here folks.

[beetroot72]

Pay no attention to the 900 pound gorilla ,nothing to see here folks.

Very Funny!
I guess with me the slop is more of a "type-a personality" annoyance. It just seems so wrong that I cant get it out of my brain. My truck drives just fine and I'm just a basher who doesn't really care where it goes when I turn! Still, it's an ongoing struggle.