Dog bone's and Pro-Trac arms

[ReaperGN]

I did a dog bone on my eagle. For the most part its the same suspension as a Stampede. You can not set the suspension as high as a cvd setup but it has no pins to cut through your arms. The only thing needed to install it is to cut the inner drive cups down a bit. There is a groove on them so its very easy to do with a sharp saw. Later this week I will post a few pics of it in my pede.

Here are the parts

86885 HPI Racing Rear Axle 5x41mm

86234 HPI Racing Cup Joint 7x19mm

86886 HPI Racing Drive Shaft 6x86mm




More pictures

http://s573.photobucket.com/albums/s.../Blue%20Eagle/

[Oaks]

Now job, man. I saw your thread over in the vintage section. Sounds like a fun project

[AbSoLooT1]

Or... Even easier if someone really wanted to... Can get the MIP CVDs for the losi xxxt. They are a bit longer, and solves the issue. MUCH cheaper and easier. at about 18 dollars. (if already as MIP 08123)

[ReaperGN]

A HPI dog bone setup is only 30 dollars making it cheaper than buying cvd's new. Its also much simpler than any cvd setup.

[AbSoLooT1]

Conclusion: HPI much cheaper if someone doesnt already own MIP 08123, 14 dollars more (total of 30), if someone already owns Stampede/Rustler MIP Cvds and just needs to adapt em to Protrac Arms.

[ReaperGN]

I forgot one part. I had some in my parts box so I never thought to share. You need 4mm set screws to hold the cup joints to the diff. Dubro offers some for only 1.47 (2170).

While looking up other part possibility's I came across some heavy duty cup joints. The part number is HPI 86314. For an extra dollar one can get a stronger cup joint that should last longer.

I also came across these but can find any detailed specs. Some people have installed 1/8 dog bones so it is possible to use these. If they would fit the HPI cup joints it would add some customization to a rather dull area. They come in orange, green, black, red, and blue.

[Oaks]

A HPI dog bone setup is only 30 dollars making it cheaper than buying cvd's new. Its also much simpler than any cvd setup.

Hey Reaper, I feel like i've seen that simple before. From the old school, is that similar to what the Traxxas Bullet had?

You told me about this setup, too. You might have already known that the 4x4 axles are working pretty well for me, but this set up is cool. Let us know how it holds up. Also, i'm wondering, are the racing rear axles the same lenght for those of us running adapters and such?

[ReaperGN]

I think the bullet used sliders. But many other buggy's and stadium trucks have used bones.

What do you mean by racing axles?

[Oaks]

In your original post...86885 HPI Racing Rear Axle 5x41mm. Are these pretty much the same size as stock?

[ReaperGN]

I see whats going on here. They are the stock part. HPI just likes to put racing after their name. Those are the outputs out at the wheel. They slide right in with no issues. They do set the pin hole out a little further. You can either fill the gap with spacers or fuel tubing like I did. The reason for the extra distance is HPI hex's sit further down onto the pin. So you could just get their hex's if you want a perfect fit. The ones in the picture are actually an older model. I had to dremel them a little bit to get clearance for the newer bones. The 86885's are 1mm longer and require no dremeling.

On a side note this setup can be used on the stock arms as well.


Also you could get these but they are a good chunk of money more.

[Oaks]

Cool man, so the extra 3mm's are already accounted for. The colored bones are pretty sweet, too. Any chance you might gear the blue eagle up for high speed, or is this truck for racing?

[ReaperGN]

I dont have enough info on the colored ones to say they will work with my parts so do not buy them until they have been verified.

As to the Eagle its geared 25/76 and never gets hot. I plan on doing some speed runs once all the bugs get worked out. It could be used for racing but that's not something I plan on doing.

Hopefully my parts will be in tomorrow so I can post some pede pictures of the bones. This setup was originally intended for a stock pede so it will bolt right in. I really want to convert the pede over so I dont have cvd pins any more. They killed my arms and carriers.

[Oaks]

Thanks for the red. Time will tell, ay? But I'll say this, I haven't been posting too much, but if youre running the motor esc combo I think you are...switch to 32P. Yeah, I ran some 19/50 and it starts to wake up, lol. I think there may be room for a 24, definitely 23 and funny enough I think a stock gear cover fits small 32P spurs without noise if you trim the front corner of the spur teeth and mesh towards the back of the gear running RRP pinions. Thanks for coming thru with the HPI goods. Dog bones/drive cups = less slack than cvds?

[ReaperGN]

Thanks for the red. Time will tell, ay? Thanks for coming thru with the HPI goods. Dog bones/drive cups = less slack than cvds?

No problem.

There is actually a little more slack with a dog bone setup. But there are no pins to worry about and they can be replaced in about a minute. Bones dont work well on the front of a RC but on the rear they are hard to beat. My 2400 will definitely find the weak points of the setup. Everybody claims that 48 pitch falls apart but that's just not the case for me. MY 3800 only ate a spur if the motor came loose and so far the 2400 has not even broken in the new 76. So I will stick with 48 until I start blowing through spur gears. Which technically should happen once the dog bones start to wear things down.

[Oaks]

Right on. I was running 25/76 and it was just mean. I was thinking about a fun video contest for the community. Street setup, 2 cones about 20 ft apart, start at one and dash for a few laps, post the vid, and let the group calc the time, lol, the 2400 is sick

[ReaperGN]

For anyone wondering why I dont just use cvd's here is your answer.

[Raptorpede]

What happened there ?

[ReaperGN]

That's what happens when cvd's throw a pin.

[ReaperGN]

Here are some pictures of this setup in a Stampede. You may need to use a few 5mm washers on the stub axles and place fuel tubing in to the cups so that the bone is setting in the proper location. And encase I forgot to mention it you should install 5x8mm bushings behind the cups on the diff. This will stop the bones from pushing the diff outputs together. If you dont there is a chance of chewing up some diff gears.

http://s573.photobucket.com/albums/s...e/Dog%20Bones/

[Oaks]

Are those nitro rustler/ 4x4 pede rear carriers?

[ReaperGN]

When I got them I didn't pay much attention. Ends up they are for the 4x4 slash and nitro models. I actually prefer them. They appear to be stronger and bend less when the wheel pushes inward.

http://www.rpmrcproducts.com/product...ires/80732.htm

[Oaks]

That's the rumor, thanks for the confirmation. I hear the TRX aluminums ones are adjustable adding and extra degree of - toe?

[ReaperGN]

Not sure if they do or dont. The nitro's use arm mounts separate from the trans so I know those are adjustable. On my eagle I reduced the Pro-Trac toe in by one degree and am very happy with it.

[scootroc]

I have all the parts to make this happen. My question is: are there any problems with tossing the bones out with a brushless system?

[ReaperGN]

I have not had any issues with that. And the rig I run them in had a Castle 2400 running on 3 cell lipo. There is a chance of it happening if you dont align the bones properly. I am using different carriers that appear to stick out a bit further than On my Blue Eagle. Give me a couple minutes and I will check the fit with standard carriers.

[Oaks]

I like how those carriers stick out a pinch further for the hex pin. How does the bushing work behind the inner drive cup?

[ReaperGN]

You will have to use washers to position the stub axle and fuel tubing to position the bone.

Here is about were the bone should set.




This shows how much space needs to be filled with washers.




This one shows how far out the stub axle can move.




And this one shows about were the bone should set in the diff cup.

[ReaperGN]

I like how those carriers stick out a pinch further for the hex pin. How does the bushing work behind the inner drive cup?

When the cup pushes inward it will also move the diff output inward which will cause the diff gears to eat each other. The bushing will limit movement by hitting the bearing in the trans case and not allowing the diff output to go any further. You could also use washers.

[AbSoLooT1]

"if" you choose, this would be good information to have on the . "everything you need to know about Protrac" thread. its a good option. Thats if you deciede to post it there. If you do, I think itd be good because alot of folks go to that thread with protrac questions.

http://traxxas.com/forums/showthread...Massive-Thread.

Or at least post a pic or two, and link this thread there so the information doesnt have to be repeated, either way. Il leave it up to you.

[Oaks]

Good call Loot. It would be cool to see that thread include tuning info and tweaks for max performance. I wanted to add some shock position change related info for those who want to experiment. Maybe we could get some hard data back from testing and configuring shock placement and camber link changes

[ReaperGN]

Here is a slightly cheaper setup. It only costs about 25 dollars. The only downside is the hex pins are a bit thin. I have not tested it yet but evaders seem to do just fine with it. The axles also fit better than the HPI ones.

Cup Joints - DTXC8100
Axle's and pin's - DTXC6179
Bones - DTXC7457








Note: The cup joints have to be trimmed a bit for the bones to fit. It takes about 10 minutes with a dremel.

[Oaks]

Reaper, I really like the DTX setup, also. Keep us posted on the durability of the new setup.

[Dr. Isotope]

Tekno M6 setup for Slash 2wd. Cut the bone in half in the center, sleeve into a tool steel rod drilled to the same size as the bone, filled with JB-Weld. Set to 4" long. Let harden for about a week. Put heat-shrink over the whole job to nice up the look.


I've put 50+ packs through them.

[ReaperGN]

Here is a little update on the Duratrax setup. It works perfect on 2s. But the hex pins are to small and tend to break. To fix this just drill them out with a 5/64 bit and you can run the industry standard. Also dog bones are way nicer when things go wrong. Instead of chewing up your arms and carriers they simply fall out. This can be a problem in tall grass so if your running a ball cup setup you might want to keep a few spares in your box. If your thinking they fall out all the time then dont worry. That only happens if things are to loose. To space the bones properly you can use springs or fuel tubing.

[MidnightPumpkin]

I have the protrack arms on my build, is there a different transmission cup that can be used? The MIP has two grub screws that tighten down on the flats, I am concerned, and that is why I changed the cvd's on my other pede to the through hole type. The FLM diff does not have that, just flats

[ReaperGN]

There are a few different sets of planetary gears you can put in that diff. For the dog bone setups in this thread ones without holes will work better. The out drive cups use a larger grub screw so that if you get one with a pin attached you will have to drill out the diff output to accept the larger pin.

If you need outputs with holes here they are. But you will have to drill them out for these dog bone setups or just use a single grub screw like I am.

http://buy.traxxas.com/product_info....oducts_id=4867

[MidnightPumpkin]

Reaper, does 86234 HPI Racing Cup Joint 7x19mm cups you mentioned at the beginning fit with the MIP CVD's? I bought racer's edge boots for the cvd so the pins would not come out, and they worked great for years, just not happy with the small grubs on the transmission cup MP

reading the post above, it appears that they do, with modifacations

[ReaperGN]

MIP uses a much larger bone than the standard dog bone setup. Even if you can get the pins to fit the base will be to large to fit into the cups without removing so much materiel that the cups may fall apart. There are cvd setups you can get that will fit into the cups mentioned in this thread but that kind of defeats the purpose. I cleaned the dust off dog bone setups so that there were no pins to throw and a cheaper/stronger alternative to MIP cvd's.

Now if your outputs have the hole through them then you can use a set screw with a pin on the cups you already have. The pin is smaller than the screw so it wont hit the other threads.

[MidnightPumpkin]

Reaper, I picked up the gears with the hole and I will swap out the outdrives in the FLM. I have a set of Intergy cvd's that require the hole so I will go that route. This is the same setup that I am running on my other pede which is holding up so far. I will keep this thread in mind if problems arise, Thanks MP

[MidnightPumpkin]

Does the slash have a cvd set that will work with the protrac arms?