Plastic shock ends are wallered out on revo 3.3

[corneileous]

But hey, since were talking about shocks an aftermarket shocks, I have a question that I can’t get cleared up about the different options of springs that come with those hot racing shock absorber sets that that I ordered.

I’m trying to figure out how the blue springs that I think will come pre-mounted on the shock absorbers and the chrome plated springs that come as an option are compared to the Traxxas cool springs because the pound rating or whatever it is that hot racing uses to describe their blue with their silver rings does not seem to be the same as how Traxxas describes the spring rates of their springs.

Example given, I run the tan Traxxas springs on the back which are 23.4 lb/in (4.1 N/mm) and the gold springs; 21.7 lb/in (3.8 N/mm) on the front. Hot Racing says their chrome stiff springs are a 6.8lb rate and their blue medium springs are a 4.2lb rate. The guy at hobby ECT who sold me the shocks said that the chrome springs are a lot stiffer than even the 90 mm black springs for the Revo 3.3 but their medium blue Springs, I think he said were somewhere between the gold and the tan traxxas springs. How is he (or hot racing) coming up with those numbers because the numbers that Traxxas uses is obviously not the same numbers that hot Racing uses to define their springs?

 

[olds97_lss]

I've never had hot racing shocks, so I can't say. TBH, I never compared the RC Raven springs to other traxxas springs... lol!

As for the shims on the posts, the photo I put in here earlier shows you what they do:

You can see the top of the post is lower than the top of the inner race of the top bearing. So when you tighten the bolt down, it's only tightening the inside race against the shims/spacers down to the inside race of the bottom bearing. The space that the shims take up is a hair more than the thickness of the between the bearing seats in the rocker arm. If you shim it right, you will have a tiny bit of play with the bolt tightened when you pull up on the rocker.

When I took that photo, I had an extra shim under the bearing to make the space a bit more exaggerated and easy to see.

 

[corneileous]

I've never had hot racing shocks, so I can't say. TBH, I never compared the RC Raven springs to other traxxas springs... lol!

I dunno, I’ll just have to take the guy’s word for it that sold me the stuff about where he said the springs that come with those shocks compare to the Traxxas springs.

As for the shims on the posts, the photo I put in here earlier shows you what they do:

You can see the top of the post is lower than the top of the inner race of the top bearing. So when you tighten the bolt down, it's only tightening the inside race against the shims/spacers down to the inside race of the bottom bearing. The space that the shims take up is a hair more than the thickness of the between the bearing seats in the rocker arm. If you shim it right, you will have a tiny bit of play with the bolt tightened when you pull up on the rocker.

When I took that photo, I had an extra shim under the bearing to make the space a bit more exaggerated and easy to see.

I guess I’m just not seeing that area as being my problem. I mean I guess it could be, I dunno. I’ll just have to wait til this weekend to mess with it more to try and figure out exactly where my binding is coming from when I tighten the screw. It just really seems like I need to find a shim washer that’s the same size inner diameter as the screw hole on the post with an outer diameter no larger than the diameter of the rocker arm post to go between the top of the post and the bottom of the screw.

 

[corneileous]

Here’s some pics that shows my issue. Is it possible to find some shims that are I guess the same outside diameter as the rocker post but are the same size inside diameter as the post screws?

 

[olds97_lss]

Yes, that is the issue I had. I was unable to find any 4x1mm shims that would effectively raise the bolt head, which is why I did what I did by using inside races of bearings and 5mm shims to space the bearings apart.

Don't know why I didn't think about it at the time, but you could probably use 4mm ID bearings inner race. May need to stack them up on a bolt, put them in a dremel and file down the race grooves some. Then you would need 5mm shims to take up any extra slop.
https://www.fasteddybearings.com/4x7x2-5-metal-shielded-bearing-mr74-zz/
https://www.amazon.com/CRC-Shim-Set-5mm-20/dp/B0006O4CRC

 

[corneileous]

Yes, that is the issue I had. I was unable to find any 4x1mm shims that would effectively raise the bolt head, which is why I did what I did by using inside races of bearings and 5mm shims to space the bearings apart.

Is that what size I need? Or what are those measurements, 4mm’s around and 1mm thick, or what?

I wonder if I could just grind away a little bit of material on my rocker posts on top of the hex nut where you put a wrench on it to tighten the post to the car? Yeah, the posts would be too long for the stock rockers of I ever decided to go back to them but it’s a whole lot easier to make them shorter with a thin washer below the bottom bearing than it is to find a shim that’s exactly the same size inner diameter as the threaded hole and the same exact outer diameter as the rocker post itself.

 

[olds97_lss]

4mm ID
5mm OD

The bolt is 4mm.
The bearing is 5mm.
Thickness of .5mm-1mm or so.

I think all I found were 4x6mm as a 4x5mm shim is so narrow it would likely tear/distort if you tightened down on it.

In the end, it's a stupid problem to have and I've given you one proven way to deal with it by adding a crush spacer and a potential second way to extend the post with a 4mm bearing inner race.

 

[corneileous]

4mm ID
5mm OD

The bolt is 4mm.
The bearing is 5mm.
Thickness of .5mm-1mm or so.

I think all I found were 4x6mm as a 4x5mm shim is so narrow it would likely tear/distort if you tightened down on it.

In the end, it's a stupid problem to have and I've given you one proven way to deal with it by adding a crush spacer and a potential second way to extend the post with a 4mm bearing inner race.

I found on hot racing’s website a 4x5.4mm, 1mm thickness steel shim but I’m assuming that wouldn’t work because that extra .4mm’s of the shim would be overlapping the inner race of the top bearing and defeat the purpose of trying to minimize the tightening force of the screw to the top bearing.

But even though I still don’t understand how adding cylindrical spacers stacked up on the rocker arm post between the top and bottom bearings is gonna make the rocker arm stem longer so that the screw doesn’t apply any pressure at all to the top bearing but either way, I don’t even have any old bearings I could use to try and fix my problem that way.

But when you had to deal with this issue, did you have to shim all four rockers, or just one or some? I would hope that their manufacturing process would be true and the same as all the others to where if one would essentially be too tall, they all would.

I just wish hot racing would answer their emails because it’d be really nice to see what their solution is bein’ that they made their rocker arms thicker than what they’re replacing.

 

[olds97_lss]

I had to do all 4 on all 3 of my current revo's with the rockers I have on them. The brands are integy and hot racing. I had one set of integy front rockers that were P1 (didn't have P2's available at the time) and those were the only ones that fit without shims. I've since replaced them with a set of P2's.

What the shims do is lock the distance between the bearings via the inner race. The screw tightens on the inner race. The spacers/shims are stacked so that when the center races are tighted via the screw, the outer race is essentially floating .5mm or so above the base of the seat in the rocker. My rockers move up and down about .5mm. I shimmed them as close as I could with what I had.

 

[corneileous]

Hello everybody. Just a quick update, I got my problem solved with those new aluminum rockers. Since I took my front shocks off to change a few parts on them, I decided to pick up one of those new rockers and began figuring out what I could do to essentially make the threaded post that the rocker sits on so that when you tighten up the screw on top, the screw actually tightens against the top of the post and not the bearing which was causing the rocker to barely turn with quite a bit of resistance- well, I came up with the idea to grind away some material on the top of the hex that you put the wrench on to remove the rocker posts from the chassis and I was able to whittle away enough material so that now, the screw tightens against the top of that threaded post instead of the inside race of the bearing. I put them on, tightened the screw and they rotate dang near as easy as the stock rockers so, problem solved, I can finally use my new aluminum rockers I got from Hot Racing what, 8, 8 months ago? Lol.
Thanks everybody for your input.

 

[olds97_lss]

Yeah, same issue as what I had. Just needed a crush spacer between the bearings. Hopefully grinding on the post didn't make it weak. I tend to bend those and replace them at least once a year on my revo's when I'm running them. Would really suck if it snapped off in the bulkhead.

 

[corneileous]

Yeah, same issue as what I had. Just needed a crush spacer between the bearings. Hopefully grinding on the post didn't make it weak. I tend to bend those and replace them at least once a year on my revo's when I'm running them. Would really suck if it snapped off in the bulkhead.

Well, for whatever it’s worth, I was real careful and only ground the way maybe a 32nd of an inch off the top of the hex part that you put the wrench on to either remove or install that rocker post into the chassis. It didn’t take a whole lot. I was real careful about not touching the shaft that has the threads in it that the screw threads into that holds the rocker on there so, I guess if I do happen to break one, it’s not that hard to order a replacement. And besides that, I think Hot Racing actually sells their own version of those rocker posts so who knows, theirs might actually be made to where you can use their aluminum rockers with your bearings in them and they’ll probably fit down on that shaft exactly the same way the plastic Traxxas rockers fit down on the stock posts.…

But yeah, I still don’t understand what you were talking about when you were saying to use those crush washers or whatever it was you were talking about between the rocker and the bearing because the problem at hand was the fact that those hot racing rocker arms were made taller than the factory Traxxas plastic ones. The very top of that post was not long enough for those rockers. That’s why when I went to tighten the screw down to hold the rocker secure, the flat part of the screw was putting to much pressure on the bearing itself rather than on the top of the post. I really don’t see how adding anything between the rocker and the bottom bearing was going to make that rocker arms shorter. But oh well, I’ll try this to see how it works.

 

[olds97_lss]

The shims/spacers go between the bearings and only make contact with the inner race of the bearing, which is what the screw head touches that causes them to bind by putting load on the center race of the bearing due to the outer race/seat being too tall. By putting spacers/shims in there, the bearing is fully supported in the center, so it cannot put side load on it when you tighten the screw.

Notice in this photo, the post inside the bearing is shorter than the inside race of the top bearing now:

That bit of space is how much shimming it took to make it not bind when the bearings are in the rocker pivot I used.

 

[corneileous]

The shims/spacers go between the bearings and only make contact with the inner race of the bearing, which is what the screw head touches that causes them to bind by putting load on the center race of the bearing due to the outer race/seat being too tall. By putting spacers/shims in there, the bearing is fully supported in the center, so it cannot put side load on it when you tighten the screw.

Notice in this photo, the post inside the bearing is shorter than the inside race of the top bearing now:

That bit of space is how much shimming it took to make it not bind when the bearings are in the rocker pivot I used.

Yeah, I remember you telling me about that last summer but see, here’s the million dollar question- I guess if I would’ve realized this then, I would’ve asked you along time ago but it just now came to me but if all you did was just put spacers on the shaft between the bearings, are you essentially still tightening up your screw against the inner part of the top bearing? See, that’s what screwing me up on what you did because by looking at that picture zoomed in, the inner part of your top bearing is actually quite a bit taller than the top of that threaded post so, that’s why I can’t see how what you did with those spacers is allowing you to tighten that screw up without putting everything in a bind that keeps the rocker from rotating.

 

[olds97_lss]

are you essentially still tightening up your screw against the inner part of the top bearing?

Yes. The issue with the aftermarket rockers is that the seat the outer race of the bearing to sit in is too far apart, which makes the inside race stick up above the post. So when you tighten the screw, it's putting side load on the bearing by crushing the inside races together from the side.

By putting spacers between the inner races, I'm not allowing the inside races to move when the screw is tightened. This is creating a bit of slop between the outer bearing seats in the rocker. So with the screw fully tight, I can move the rocker about .1-.2mm up and down because the outer races are now further apart than the seat that's milled into the rocker.

One of those things I suck at explaining and was a bit of an "ah ha" moment when I sorted it out.

With the first set, I actually took a dremel to the rockers by dremeling material off the inside race. It was a real pain to do and the rocker being aluminum, would get hot, fast. Took me over an hour just to do the first one. With arthritis in my hands... I could barely pick up my coffee the next day after that.

 

[corneileous]

Yes. The issue with the aftermarket rockers is that the seat the outer race of the bearing to sit in is too far apart, which makes the inside race stick up above the post. So when you tighten the screw, it's putting side load on the bearing by crushing the inside races together from the side.

By putting spacers between the inner races, I'm not allowing the inside races to move when the screw is tightened. This is creating a bit of slop between the outer bearing seats in the rocker. So with the screw fully tight, I can move the rocker about .1-.2mm up and down because the outer races are now further apart than the seat that's milled into the rocker.

One of those things I suck at explaining and was a bit of an "ah ha" moment when I sorted it out.

With the first set, I actually took a dremel to the rockers by dremeling material off the inside race. It was a real pain to do and the rocker being aluminum, would get hot, fast. Took me over an hour just to do the first one. With arthritis in my hands... I could barely pick up my coffee the next day after that.

Man, I don’t mean to sound like a broken record and if I do I sincerely apologize but see, that’s just the part that keeps confusing the heck out of me is because I just don’t see how putting spacers where you say you put them actually corrects the problem because for one, how do you even get spacers in there anyway because once you slide that rocker arm down over the post, that whole shaft is covered up. The problem that I first ran into when I tried my new rockers before I started breaking out the Dremel tool was that the stem the top screw screws into was actually tightening up against part of the bearing that slides over the shaft rather than on the top of the shaft like it does with the original rockers which is why I’ve always said from day one that the top hole on the top of the rocker didn’t seem like it was cut down deep enough so that when you put the bearing in there the inner part of that bearing drops below the top of that shaft so that like I said, when you tighten up the screw to secure the rocker arm to the post, it tightens up against the top of that shaft rather than the bearing which is what allows it to rotate freely.
Oh well, this way did work and I really didn’t have to take away that much material on top of the wrench hex to get the new rockers to go down further on the posts.

 

[olds97_lss]

Glad you got it to work for you. Without taking a dremel to one of my rockers to show you why the spacers work, I can't think of another way to explain it.

 

[corneileous]

Glad you got it to work for you. Without taking a dremel to one of my rockers to show you why the spacers work, I can't think of another way to explain it.

I took my revo out this afternoon for a single tank run to do a little more fine tuning to the carburetor and it ran great on the new rockers. Of course, I got rid of those cheesy shocks I got from Hot Racing and just put the original shocks back on but with new aluminum rod ends from Hot Racing.

 

[olds97_lss]

I just took the rear shocks off my ERBEv2 to replace he RC Raven dual rate springs with traxxas blue. I replaced the VDK#2 pistons in the rears a few bash sessions ago due to breaking one of the pistons for the 3rd or 4th time and went back to standard #2 pistons and 50wt. Should have changed the springs then, but it wasn't until I modified the RPM truetrack to fit the thing that I noticed it while I was adjusting the pivot ball cap. Poor thing didn't rebound at all after being compressed.