Big Rock Hot Racing Bell crank for big Rock. Servo arm screw hitting chassis.

[Ragga]

Hi Fam,

Installed the hot racing bell crank with the hot racing servo saver and a new 25k servo.

After installing the HR bell crank, the screw on the servo arm is hitting the chassis and not allowing full movement. Has anybody had that problem?

I had to reinstall the original big rock bell crank and everything works correctly.

Any suggestions on why would the servo arm screw keep hitting the chassis with the hot racing bell crank installed?

Do I need some kind of spacer somewhere to make the servo sit higher? Or do I need a flat screw instead of the rounded raised one that goes into the servo arm? Or am I doing something wrong? Watched videos and nobody else had that problem.

Thank you.

 

[morrjr71]

Hi Fam,

Installed the hot racing bell crank with the hot racing servo saver and a new 25k servo.

After installing the HR bell crank, the screw on the servo arm is hitting the chassis and not allowing full movement. Has anybody had that problem?

I had to reinstall the original big rock bell crank and everything works correctly.

Any suggestions on why would the servo arm screw keep hitting the chassis with the hot racing bell crank installed?

Do I need some kind of spacer somewhere to make the servo sit higher? Or do I need a flat screw instead of the rounded raised one that goes into the servo arm? Or am I doing something wrong? Watched videos and nobody else had that problem.

Thank you.

A pic of the problem would help us to help you.

 

[🇺🇸 DΞזΞפּ 🇺🇸]

this is a Typhon with the HR bell crank and HR servo saver
The linkage will slightly rub the body so I just cut a small piece of the corner.

 

[Ragga]

A pic of the problem would help us to help you.

Good idea. I should have done that. I just have to reinstall the HR bell crank back in though haha. May take me a couple days.

this is a Typhon with the HR bell crank and HR servo saver
View attachment 198712

Ok I see. I think it’s different than the big rock though? Servo is upside down on the big rock. Typhon looks right side up and free and clear from anything.

 

[drkern88]

I had a similar problem on my Typhon. I ended up keeping the HR servo saver but using the stock linkage

https://www.arrmaforum.com/threads/...d-questions-on-performance.47942/#post-674527

I also tried using a flat head screw instead of the rounded one and it still hit the chassis, causing it to bind up. I was really only interested in the servo saver part (25t) so I was happy to abandon the HR link. My steering is pretty tight now and I'm happy with it. Although I credit the removal of the slop from my steering to the Traxxas 5525 rod ends that I've put on

 

[morrjr71]

Good idea. I should have done that. I just have to reinstall the HR bell crank back in though haha. May take me a couple days.

Ok I see. I think it’s different than the big rock though? Servo is upside down on the big rock. Typhon looks right side up and free and clear from anything.

The servo mounting is different for the 6s series, which I believe is what the picture shows.

 

[pug]

this is a Typhon with the HR bell crank and HR servo saver
The linkage will slightly rub the body so I just cut a small piece of the corner.
View attachment 198712

That's a Typhon 6s, not a 3s.

 

[islandlife]

I had a similar problem on my granite using 25kg and 35kg amazon servo’s. I 3d printed some 2mm spacers to go between servo and chassis.

 

[Ragga]

I had a similar problem on my Typhon. I ended up keeping the HR servo saver but using the stock linkage

https://www.arrmaforum.com/threads/...d-questions-on-performance.47942/#post-674527

I also tried using a flat head screw instead of the rounded one and it still hit the chassis, causing it to bind up. I was really only interested in the servo saver part (25t) so I was happy to abandon the HR link. My steering is pretty tight now and I'm happy with it. Although I credit the removal of the slop from my steering to the Traxxas 5525 rod ends that I've put on

Oh ok. Thanks for the info!

I had a similar problem on my granite using 25kg and 35kg amazon servo’s. I 3d printed some 2mm spacers to go between servo and chassis.

3d print! Nice!

 

[Velodromed]

Hi Fam,

Installed the hot racing bell crank with the hot racing servo saver and a new 25k servo.

After installing the HR bell crank, the screw on the servo arm is hitting the chassis and not allowing full movement. Has anybody had that problem?

I had to reinstall the original big rock bell crank and everything works correctly.

Any suggestions on why would the servo arm screw keep hitting the chassis with the hot racing bell crank installed?

Do I need some kind of spacer somewhere to make the servo sit higher? Or do I need a flat screw instead of the rounded raised one that goes into the servo arm? Or am I doing something wrong? Watched videos and nobody else had that problem.

Thank you.

A couple silicon spacers helped mine. Small washers would do the trick also.

 

[Ragga]

A couple silicon spacers helped mine. Small washers would do the trick also.

Thanks! Where do you put them?

 

[Velodromed]

Thanks! Where do you put them?

Under the servo and through the screw at each corner. Like reverse washers basically.

 

[Ragga]

Under the servo and through the screw at each corner. Like reverse washers basically.

Yes!!! I think that will work. Thank you!!

 

[🇺🇸 DΞזΞפּ 🇺🇸]

That's a Typhon 6s, not a 3s.

Ahhhh maybe his picture would have been more helpful lol my bad

 

[Ragga]

Ahhhh maybe his picture would have been more helpful lol my bad

Haha it would have been helpful for sure. No no, my bad.

 

[GRC]

I think I know which screw you're talking about. The screw that attaches the servo link to the bell crank. The one that you can see/screw in through the hole in the chassis right? That screw comes very close to the chassis, but it shouldn't touch. I've used the Hot Racing bellcrank without a problem. Most likely you didn't connect the servo saver, servo link, or bellcrank correctly and something is pushing the screw down. It can be a little confusing which parts go over and under each other. Or maybe a bearing fell out of your Hot Racing bellcrank? Check that all four are there.

P.S. The Hot Racing bellcrank doesn't improve performance. I've ditched it and gone back to stock plastic. If you're actually breaking bellcranks, the Hot Racing may be more durable. But I don't think many people break bellcranks.

 

[Ragga]

I think I know which screw you're talking about. The screw that attaches the servo link to the bell crank. The one that you can see/screw in through the hole in the chassis right? That screw comes very close to the chassis, but it shouldn't touch. I've used the Hot Racing bellcrank without a problem. Most likely you didn't connect the servo saver, servo link, or bellcrank correctly and something is pushing the screw down. It can be a little confusing which parts go over and under each other. Or maybe a bearing fell out of your Hot Racing bellcrank? Check that all four are there.

P.S. The Hot Racing bellcrank doesn't improve performance. I've ditched it and gone back to stock plastic. If you're actually breaking bellcranks, the Hot Racing may be more durable. But I don't think many people break bellcranks.

Yes that’s the screw! Ok I will check all when I go and take it apart again. So it doesn’t improve steering? Maaaan. I’m definitely breaking bellcranks.

On the servo saver, I’m wondering if I have it screwed down enough now. I do see a little bit of metal from the servo. I screwed the servo saver down more and the screw was hitting it less. The screw is very tight afraid to go too tight. Should the servo saver completely cover up the metal part it sits on from the servo?

Thanks for the info!!

 

[Velodromed]

Yes that’s the screw! Ok I will check all when I go and take it apart again. So it doesn’t improve steering? Maaaan. I’m definitely breaking bellcranks.

On the servo saver, I’m wondering if I have it screwed down enough now. I do see a little bit of metal from the servo. I screwed the servo saver down more and the screw was hitting it less. The screw is very tight afraid to go too tight. Should the servo saver completely cover up the metal part it sits on from the servo?

Thanks for the info!!

I also tried one and ditched it. I just bought several new steering sets from Jenny’s for a few bucks each. They include the servo saver also. Then I bought several s652 servos from 6s models ($17each). When steering lags or fails on one of my 3s cars I swap all or part out. Some upgrades just add weight and these 3s cars for bashing do not need the extra weight.

 

[Ragga]

I also tried one and ditched it. I just bought several new steering sets from Jenny’s for a few bucks each. They include the servo saver also. Then I bought several s652 servos from 6s models ($17each). When steering lags or fails on one of my 3s cars I swap all or part out. Some upgrades just add weight and these 3s cars for bashing do not need the extra weight.

Oh ok. Cool. Thanks again. Very helpful!

 

[GRC]

On the servo saver, I’m wondering if I have it screwed down enough now. I do see a little bit of metal from the servo. I screwed the servo saver down more and the screw was hitting it less. The screw is very tight afraid to go too tight. Should the servo saver completely cover up the metal part it sits on from the servo?

Not having the servo saver pushed all the way onto the servo could definitely be a reason that screw is too low. I'm able to push my servo saver all the way before using the screw. If you need the screw to push it all the way, you may have not put it on right.

Arrma Spektrum servos are 23t. Most other servos are 25t. The Hot Racing servo comes with 3 different adapters (23t, 24t, 25t) Using the wrong one would make it difficult to push the servo saver all the way down.