Are the GH knuckles any good?

[MooseSlash]

Like the title says, are they? I've heard that they are great, and they are bad, input anybody? Thanks!

[jimbo74]

the gh and gpm are the only knuckles i would currently run

i do have the gpm, the gh are fine as well

[BomberSTi]

Im running HR knuckles and i have no complaints i love them. haven't had any issues yet. me and my friend were running our trucks last night and he's got the mini summit with rpm knuckles and we bumped last night tire to tire in some side by side racing and his front left popped out both pillow balls and mine kept cruising.....so they have been passing my testing so far...

[BigFlash]

Ive been running GH on the front of my MERV for a while and don't have a single problem. they only kinda issue i have with them is the one bearing is a tight fit and can be tricky to get out.

[Mossie]

if i must take a shot , GPM ones are superB

but GH will do the job also

[chilidillo]

I've been running HR for about 6 months with no problems

[DiggerPede]

Kewl info. I was curious about the GPM myself. They look really nice, but the HR ones are just awesome look'n.

[jimbo74]

hr makes awesome looking stuff, and for the most part, i endorse them. however, their knuckles seem to have a 50/50 rate of threading issues... and for $20, i'm not willing to risk it, when there are no issues with the gpm or gh

[devildog88]

^ nailed it

[MooseSlash]

Thanks, guys! Lookin' at A Main right now at their price!

[multidookey]

i think there was a thread like this a while back that i read. not being mean just transferring info. and one guy i forget who it was wrote a super long story about his findings and he said that the hotracing were good for a while but started to were out because the inside is a circle so when your turning and if the suspension flexs it will limit your steering and the pillow ball will hit your knuckles and he said that the gh gpm rpm and even stock have a more squared out area so that it can get that added range of motion. and i will try to find a like to that post and post it. i hope this info helps though. and ones again this isnt really my story. just one that i heard.

Good call, i wanted to write a bit about my recent knuckle experiences anyway..

First, i never run the stock knuckles. I started with the RPM plastic knuckles at the rear and HR alloy at the front.
I got on pair of RPM for free and then added the HR before i even had a motor. That was last year.
I thought the front will take more stress, suspension up/down + steering, while the rear only take the suspension movement. So i put the HR alloy on the fronts and the RPM plastic in the back when i got my first motor.

HR alloy: With a proper hextool a now brainer to install and setup at first.
RPM plastic: Quite a bit finicky for my taste. The retainer caps are hold by two tinytiny screws each. These screws are weak and easy to strip. Managed to damage one and destroy another during the first install. Tricky to setup, but when you get it rite, the RPMs are great, very little play with still enough movement to not bind.

Well on the third run i had the first one of the famous pillow ball pop-outs on the RPMs. I could pop it back in with some axle grease, but not fun. That was after six packs 2S Lipo onroad. And this developped a habit. On subsequent runs i had more and more pop outs. Didnt took long to find out that the big bearing hole/carrier, facing the inward side, ovaled out badly. In the end you could see a gap with light coming throught between the bearing and the knuckle.

I got a pair of the GPM alloy silver as replacents for the RPM after that. Install was soso for me. The threads for the collars were not cut that proper, so i tend to strip the delrin collars on one knuckle while screwing them in. But once setup these neednothing to no attention, they simply work in my case. After about a year in use they look totally beaten up, dented and sandblased from my dirt running. But still going strong.

In contrast the HR alloys on the front needed some adjustments every other run on the lower collars, they are metall with a delrin washer facing the pillow ball and tend to come a bit loose every now and then. But overall i was ok with them for nearly one year. And i really liked the look.

I think it was last week, that one lower front pivot ball on the HR alloys started to pop out. Try to pop a pivot ball back into an alloy knuckle in the field...
Managed to repair the worn out alloy knuckle at home somehow with a few hits with a hammer. Then the next run i noticed suspension binding on the other front knuckle. After further inspection I found both HR alloy front knuckles are too worn out on the lower pivotball holes and have too deep kinks to safely hold and operate the ball at sharp turn/jumps. So i ordered GPM replacements for them too.
And after a couple of runs I can say I love the GPM way more then the HR in the front. You can set them tighter without steering binding, which allows more precise handling.

I think i just realized that the HR knuckles have some inherent design flaw, which make them weaker then other alloy designs for setup and durability: The opening facing the pivot ball is all round on the HR, whereas most other knuckles (including the stockers) have a more square pillow shaped opening. That may give better support and minimizes stess and wear.

I run high offset wheels, so that might put more stress on the knuckles then normal stance or light offset wheels?

Long story short, from my experience after one year, if you want a reliable, lasting knuckle go GPM. Or GH or Integy which seem to have a similar design as GPM.

So much text, I'll give you some pix to cheer you up a bit.

Fresh GPMs


Worn out HRs



Used GPMs, doing their duty on dirt



this was posted by CMD-J and heres a link to the thread its called 1/16 knuckles (axile carriers) if the link doesnt work
http://traxxas.com/forums/showthread...acing+knuckles

there were also pics on his post and i see they didnt go through. so if you want to see them go to the thread.

[MooseSlash]

Thanks multidookey! That was one of the most helpful posts I've ever read.

[chilidillo]

Maybe I'm all wet, but aren't the GPM knuckles a round peg in a square hole? Had GPM's for a short while and had 2 pivot balls break at the base of the ball.

[multidookey]

no problem. i read that and thought it was great and seeing this reminded me of it. so yeah no problem. and chilidillo idk i havent gotten them yet im still waiting to get enough money. and from what i have seen its like a square whole that is rounded out a little. and that is supposed to help when turning and then the suspension moves. and if that is where they broke then maybe your suspension was traveling to much? because they are in the square so that is doesnt put as much strain on the pivot ball.

[DiggerPede]

Hmmmm.....glad ya'll passed the info along. Not that i'm currently looking to replace the RPM as of yet. But good to know when i decide to.

[Mossie]

i did see on topics on other forums that their are PPL who crack the HR Knuckles

not all but a few

[minirevobasher]

For GH aluminum knuckles for $15, are they better then the rpm ones? Since i only have problems of pivot balls popping out in the front, i think i will do aluminum in the front and rpm in the rear.

[jimbo74]

my rpms popped out in the rear also, just not as much.... also.... the rear rpms and fronts severly ovaled out the holes, you could actually see light around the bearing when held up to a light


gh knuckles as well as the gpms are far superior to rpm, stocks, or otherwise

[minirevobasher]

my rpms popped out in the rear also, just not as much.... also.... the rear rpms and fronts severly ovaled out the holes, you could actually see light around the bearing when held up to a light


gh knuckles as well as the gpms are far superior to rpm, stocks, or otherwise

So you think GH will be ok?

[jimbo74]

So you think GH will be ok?

yup.... in the second post in this thread i said:

the gh and gpm are the only knuckles i would currently run

i do have the gpm, the gh are fine as well

[multidookey]

honestly i also must say that i do think that the best are gh or gpm and the rpm are good (better served for the on roads since they don't get as much strain) but if you put the hr in the rear then what i said about the steering and suspension travel i should retract. because in the rear you don't have to worry about that since it only moves up and down. but in my preference i have rpm on my rally and gpm around my merv and gpm font on my slash and gh on the rear of my slash. and with all of those setups i have never had a problem with them.

[minirevobasher]

The only reason im holding back on the rpm are because of popping out. I only seem to pop out ones in the front though so thats why i was thinking aluminum up front and rpm in rear.

[multidookey]

well i would say if you run into stuff alot (not cartwheel) then you could probably get away with rpm rear and gpm or gh in the front. but if you do cartwheels and land rear straight down on jumps then get gpm or gh all around. just to be safe i would get aluminum all around because its a pain to put them back in after they come out and it just gets annoying.

[BigFlash]

i'm with jimbo. My RPM's on the rear ovaled out rear bearing mount. I would say for any of the wide wheelbased mini's to stay away from them. On the other hand my rally has had rpm on the front for a while now and have no issues.

[CMD-J]

Yeah, i think that nailed it pretty good. Plastic RPMs seem to be perfectly fine on the smaller wheeled 1/16, like Rally, Fiesta, Mustang -maybe even the Slash. But not so much recommended on the MERV, Summit and Grave Digger with heavy and offset wheels.

[NITRO FUMES]

Two thumbs up for the GPM alloy knuckles !! As a manager of the car department at a local
hobby shop we get to see a ton of different products run past our counter. Just installed a
full set on my merv when I did my BBC for some added strength and durability. Formally ran
the RPM knuckles with no problems when set up correctly. GPM has great finish and fit well
with none of the problems of cross threaded pivot ball caps like i have heard with the HR knuckles