Yeti Dlux Ofna Kit Install

[A1Fiddler]

Hey guys, here are my notes from the Dlux Ofna open diff kit install. Even after going through Erik's and 802coma's threads, there are a lot of unanswered questions and little things you need to know (or figure out). Here's a list of parts I used in addition to the full kit from Dlux:

M3x6mm set screws (x4) (if using 4-40 wheel screws)
M3x21mm (or longer) screws (x2)
M3 locknuts (x2)
3mm I.D. x6mm spacer (x2)
Dremel w/ cutting & sanding bits
Flat and square metal files
3/32” steel punch
Hammer
3mm drill bit & drill
Diff gasket & oil (I don't like to reuse diff gaskets)
Red and blue Loctite

I'm using STRC caster blocks and RPM a-arms with standard 30mm bolts and locknuts to hold them together. I'm also using Crawler Innovations 6-bolt wheels and Traxxas adjustable steering/camber links with Revo rod ends

Assembling the diff is no different than usual, just use the Dlux outputs. Don't bother installing the cups yet. I will say that I would feel better if there were a flat spot machined on the output for the cup's set screw. I would think this would prevent the cup from slipping, especially in a high powered application. I did coat it with red Loctite, but I considered filing a flat spot on it which you would want to do before putting the diff together.

Update: As I suspected, the output cups started slipping a few minutes into my first run with it (easy run, stock motor). I consider it necessary to grind a flat spot on the outputs to prevent this. I did, and was able to run a full race without issue.

There are some things you need to know about the knuckles. The rounded notch on the backside goes down. You'll notice when installing the arms that if you flip it you'll have funky camber, as the holes for the top arm are set farther in than the bottom. I opted to drill out the holes in the clear spacers so that it went together easier and to make sure the arm is getting pinched against the knuckle without any gap (this is where the 3mm drill bit comes in). Install the brass bushings with the flat sides facing in toward the caster block. When bolting the knuckle arms to the caster block, you want to eliminate play without binding your steering.




When it comes to installing the axle in the knuckle, the kit includes 4 spacers - 2 short and 2 long depending on which hub setting you're using. I opted to use the narrow one. In order to install the pin, I had to file down the spacer. Do it slowly and check the fit often. You don't want any slop but I had to work with it for a while to get it to spin semi-freely (trying to account for bearing break-in). This is where the flat file, punch, and hammer come in. One thing I'll point out here that I haven't seen anyone else mention yet is that when using 4-40 screws as I am, the holes for the cross pin are exposed, allowing the pin to potentially fall out. To solve this, I inserted M3x6mm set screws into each end (with blue Loctite) to lock the pin in place.



Now you want to file everything down so you get full steering. First, I shaved down the RPM arm a bit.



Then I worked on the caster block. This part is relatively simple. Just file down the lower side of the rear of the block so it's flush with the top (hard to explain, see pictures).



Then I went to work on the knuckle. Be careful not to grind it down so far that you start cutting into the screws holding the arms on (I almost went too far on one of them). You'll need to grind the bottom of the knuckle both front and back, though much more on the back. I used my Dremel w/ cutting wheel for this with good results, but I also have a lot of experience with it. Be careful here and you may want to do this with a hand file if you don't have a real steady hand.




You also need to clearance the top of the caster block to allow the steering arm full swing. This is also fairly simple, just see the pic.



You'll need to do some grinding, put it back together, and see how it fits. Get comfortable taking it apart and putting it back together as you'll be doing it a lot. My goal was to have the limiting factor be the base of the arms against the caster block and I got to that point. With everything assembled, the limiting factor is somewhere else.




Once you're done grinding everything down, slide the output cups on and assemble the knuckles/axles. You want the outputs to solidly capture the universal shaft at full suspension compression and droop. Get it in the ballpark, then tighten the output cups down and pull everything back apart so you can grind down the RPM arms. This was fairly easy with a Dremel bit I had for grinding plastic. I recommend removing the arms, grinding, putting them back on with the shock, then testing again. It sounds like a pain but it's not difficult. Just one screw for the arm and one for the shock.




Now you want to coat the output cup set screw in red Loctite, verify the location of the output cup by cycling your suspension (watching the axle shaft in the cup), and tighten the screw. I recommend bracing the output cup with a wrench or something to prevent torquing it too much against the diff housing and o-rings while tightening it.

[nfcrockett]

Great write up. I've been considering this kit but wasn't exactly sure how much work went into installing it.

[A1Fiddler]

Originally Posted by nfcrockett

Great write up. I've been considering these but wasn't exactly sure how much work when into installing them.

Thanks. It is quite a bit of work but I think it's worth it in the end. What was annoying was trying to figure everything out and ordering a bunch of parts I didn't know I needed until after I started putting it together, hence the write-up and parts list. As far as I know this is the only option for a bulletproof front-end with the open diff. Plus I think the Ofna shafts are a better fit than the MIP shafts. Less rotating mass.

[rob4607]

So not to be a pita but if the kit is made for the yeti then why did you have to radius or shav so much off and also order so many parts? I have seen post stating "if you have RPM arms" you have to shave and radius areas to make it work, to me the guys that are going to spend this much on a front end will most likely already be running rpm arms. And secondly I wouldn't want to modify it to the point I couldn't still be able to use the stock arms in a pinch if there is a part need. I hope this makes sense, I understand some slight filing and massaging but this seems to be some serious removal of material and it would look a lot better removing it at the mill or whatever is being used.

[trig n tahoe]

My bro ninja run this set up. I don't know if he went to this extent to make it work, maybe we can get him to chime in

[fr8cture]

Woah man. Resize your pics!

[A1Fiddler]

Originally Posted by rob4607

So not to be a pita but if the kit is made for the yeti then why did you have to radius or shav so much off and also order so many parts? I have seen post stating "if you have RPM arms" you have to shave and radius areas to make it work, to me the guys that are going to spend this much on a front end will most likely already be running rpm arms. And secondly I wouldn't want to modify it to the point I couldn't still be able to use the stock arms in a pinch if there is a part need. I hope this makes sense, I understand some slight filing and massaging but this seems to be some serious removal of material and it would look a lot better removing it at the mill or whatever is being used.

That would be a question for the manufacturer.

Originally Posted by trig n tahoe

My bro ninja run this set up. I don't know if he went to this extent to make it work, maybe we can get him to chime in

I spent most of my time getting everything I could out of the steering. After all was said and done, I was actually able to turn up my steering trim over the stock setup, which is important in racing.

Originally Posted by fr8cture

Woah man. Resize your pics!

I can do that. I thought the auto-resize was good enough.

Edit: Better?

[binaryterror]

Originally Posted by rob4607

So not to be a pita but if the kit is made for the yeti then why did you have to radius or shav so much off and also order so many parts? I have seen post stating "if you have RPM arms" you have to shave and radius areas to make it work, to me the guys that are going to spend this much on a front end will most likely already be running rpm arms.

Welcome to the world of how to work on a crawler/racer. To get the best and work with a kit that isn't nationally flying off the shelves you will be doing work.

If you really think this is too much work, Traxxas makes some cool vehicles, or keep the Yeti closer to stock.

[Sapes]

I agree with rob4607 here. He bought an after market part for the Yeti. It should fit with minimal tweaking in my opinion. It shouldn't require you to remove that much material. Now wether it was designed for stock a arms over RPM? I don't know if these have been installed correctly. I'm just saying it's a aftermarket part for the Yeti and I think your Traxxas comment was rude.

[binaryterror]

Originally Posted by Sapes

I agree with rob4607 here. He bought an after market part for the Yeti. It should fit with minimal tweaking in my opinion. It shouldn't require you to remove that much material. Now wether it was designed for stock a arms over RPM? I don't know if these have been installed correctly. I'm just saying it's a aftermarket part for the Yeti and I think your Traxxas comment was rude.

DLUX makes top level high performance parts, that means he thinks not about the new user who might not even have a file or dremel. His goal is to provide the best part and might require some user work. BEST never looks at ease of install.

There are bolt on people, and there are still many who like to work on their cars and handle some more extreme modifications. Luckily there are options out there for both users it just may not be the same end result.

Did he have to clearance the arm, carrier and knuckle? No that was to get the most benefit, you could technically leave that alone if you are less apt to mod.

Also the RPM arm is very different near the diff than the stock unit. You would not need to modify as much, if at all on the Axial arms for the diff cup clearance issue.

Again, this is a small vendor offering great parts. Unlike the big name companies or Chinese part makers, DLUX has to buy every option to test against, he does not get free or even pre-release samples. To expect him to own every possible A Arm, mounting method, carrier and differing tolerances (he isn't able to get prints from Axial or other companies) just can't happen.

The Traxxas comment wasn't rude, its a fact. Traxxas took the pain out of RC by focusing on simple and bolt on goodies. Take it as you will, this mod and its benefits are extreme durability and steering levels. If you want that from your Yeti, you will have to do some modifications. If you just want durability and slight improvements, there are plenty of available option parts and companies who just produce the same Axial part in other materials. To each their own, weigh the benefits and make a decision, not all parts are for all users.

Crawling hasn't ever had strong bolt on following due to the smaller niche market. Just like real cars/jeeps. The bolt on stuff is cool and great, but for that extra you'll not be getting a simple bolt on option, you'll be doing work.

[Sapes]

Originally Posted by binaryterror

DLUX makes top level high performance parts, that means he thinks not about the new user who might not even have a file or dremel. His goal is to provide the best part and might require some user work. BEST never looks at ease of install.

There are bolt on people, and there are still many who like to work on their cars and handle some more extreme modifications. Luckily there are options out there for both users it just may not be the same end result.

Did he have to clearance the arm, carrier and knuckle? No that was to get the most benefit, you could technically leave that alone if you are less apt to mod.

Also the RPM arm is very different near the diff than the stock unit. You would not need to modify as much, if at all on the Axial arms for the diff cup clearance issue.

Again, this is a small vendor offering great parts. Unlike the big name companies or Chinese part makers, DLUX has to buy every option to test against, he does not get free or even pre-release samples. To expect him to own every possible A Arm, mounting method, carrier and differing tolerances (he isn't able to get prints from Axial or other companies) just can't happen.

The Traxxas comment wasn't rude, its a fact. Traxxas took the pain out of RC by focusing on simple and bolt on goodies. Take it as you will, this mod and its benefits are extreme durability and steering levels. If you want that from your Yeti, you will have to do some modifications. If you just want durability and slight improvements, there are plenty of available option parts and companies who just produce the same Axial part in other materials. To each their own, weigh the benefits and make a decision, not all parts are for all users.

Crawling hasn't ever had strong bolt on following due to the smaller niche market. Just like real cars/jeeps. The bolt on stuff is cool and great, but for that extra you'll not be getting a simple bolt on option, you'll be doing work.

I'm not knocking Dlux. He stuff looks amazing. I even said I didn't know if the problem was RPM arms. That's all you had to say. It doesn't work with RPM arms. I'm done. P.S I would love to own the DLUX 1808 axles I think that's what they are called. He does amazing work.

[binaryterror]

Originally Posted by Sapes

I even said I didn't know if the problem was RPM arms. That's all you had to say. It doesn't work with RPM arms.

But as proven, it certainly does work with RPM arms.

[Sh0rtBus]

Anyone even considering this option should almost be required to read DickyT's write-up, as he was the initial tester. He made mention of needing to clearance several things during install to make it work, including the RPM arms. I agree....it is a lot of material to remove but that's part of the fun. This kit was basically designed to be the top of the line, last part you'd need to buy for the Yeti front end. Limiting factor is the wheels you want to run. And there are even options to make just about any work.

[djjiz]

Had to clearance all of my Dlux knuckles to make them work.

Does it make my stomach sick? Yes.
Does the end result fulfill my basic needs? Yes
Would I do it again? YES!

[A1Fiddler]

Originally Posted by djjiz

Had to clearance all of my Dlux knuckles to make them work.

Does it make my stomach sick? Yes.
Does the end result fulfill my basic needs? Yes
Would I do it again? YES!

Agreed, the increase in steering is a huge benefit and if I never break a shaft then it will have been worth the time and money. I ordered a Holmes Puller Pro XL motor and ESC to install now that my drivetrain is solid.

My intent was not to complain about how difficult this install is. My point is that with this guide, it's not difficult if you possess some basic mechanical skills. If I missed anything, I'll be sure and update accordingly.

[TM27]

I have the same set up on my Yeti . It was a major pain to get it set up with RPM Arms. Way too much post purchase Engineering in my honest opinion needs to be done to make it even close to usable. I do have a second question to see if you are having the same problem I am that is not something that can be fixed by a Dremel or a file . The slop in the bearings are terrible . I'm wondering if I have a set that maybe did not get checked ? The front wheels wonder all over the place . Bearings will not even work as designed with this much slop. Their website seems to be down at the moment . If you have contact info for them I'd appreciate it..

[A1Fiddler]

Originally Posted by TM27

I have the same set up on my Yeti . It was a major pain to get it set up with RPM Arms. Way too much post purchase Engineering in my honest opinion needs to be done to make it even close to usable. I do have a second question to see if you are having the same problem I am that is not something that can be fixed by a Dremel or a file . The slop in the bearings are terrible . I'm wondering if I have a set that maybe did not get checked ? The front wheels wonder all over the place . Bearings will not even work as designed with this much slop. Their website seems to be down at the moment . If you have contact info for them I'd appreciate it..

I'll PM you Erik's e-mail address. Is the slop in the bearings or is it because the spacer between the hub and the outer bearing is too small/loose? I got a bad knuckle and Erik quickly exchanged it for me. The new one has a slight amount of slop in the outer bearing but nothing that concerned me. My front-end seems fine.

[rob4607]

Binarys traxxas comment is the usual comment he makes in most threads that promotes him as the God of rc all knowing, all seeing and everyone else is wrong. Very typical of someone who will never move out of their moms basement.

Some people have lives, as it is I have enough to to tinker and perform fabrication and modifications on. House, rubicon (a real one, built not bought), 2 dirt bikes, 2 four wheelers, a 158.7 db crewmax, 2 yeti xl's, 2 yeti 1/10's, and at least a dozen other rc vehicles trust me when I say that I have the skils. My statement still stands, A product sold and marketed for anything specific should be much closer to where it needs to be as a finished product not one that has the be ground away to great lengths to make it work. I am not nocking his products at all as he has skills and comes up with some great stuff but it should be market as "here are some universal parts that will need to be modified greatly to suit your particular needs", again to many all this extra work and modification is a ton of fun, unfortunately I do not have that much extra free time. If it were some light filing and sanding I have no issues with that but remove and eighth of an inch or more is more involved than many would like is all that I am saying and that he could possibly sell a lot more if it was more finished for those of us that do not have the time.

I did end up with a ken block traxxas in a weird deal on some stuff that sits in a corner if you want it to run around in your moms basement I'll gladly send it your way...

Some days I wish this was PBB....


As for the 1808 axles they are really nice, for the price I would probably just stare at them on the dining room table forever, heck I don't want to mess up the curries on the yetis as it is!

[redsawacs]

Rob4607, your 13 yr old comments are adding nothing to this thread but drama. I think it relevant to ask you to keep your trolling posts to the chit chat section and allow the Original Post mark to continue his thread without your negativity.

If you would like to critique D_LUX, perhaps you should message him directly...

P.S. Binary has a point regarding Traxxas, perhaps you should consider what his comment actually means instead of considering it a direct attack on you. Again, I leave you with "........."

Sorry Fiddler, you may proceed.

[Erik D_lux]

Thanks for the great write up Andrew! Its always nice to have as much information out there as possible. I am sure it will be helpful.

My most sincere apologies go out to anybody who has been frustrated with my product or has had issues. I not only make parts but I use them too and I know there can be nothing more frustrating than a part that does not fit or work. I am sorry.

I know when I work on things and I have somebody elses parts, I constantly think things like "why did they to this", "why is this like this?", "This is stupid." What it really comes down to is that when youre the hobbyist, its hard to see what the manufacturer is dealing when when providing your parts. There are a lot of things you guys cannot or just dont see. I dont think anybody is trying to make crappy or hard to fit parts and certainly, nobody is trying to frustrate you.

When I build parts, I have certain priorities in mind. My priorities might go something like:
Function
Cost
Ease of install
Looks

Unfortunately, ease of install is not at the top of the list for my products and I think some are figuring that out. Its just not my top priority and for that I really do apologize.

Originally Posted by A1Fiddler

What was annoying was trying to figure everything out and ordering a bunch of parts I didn't know I needed until after I started putting it together, hence the write-up and parts list.

Curious with the statement above, what extra parts did you need that I didnt include? Looks like I forgot the steering arm screws? They should have been included. Nothing else really should have been missing unless I forgot them though, which is possible.

Originally Posted by rob4607

So not to be a pita but if the kit is made for the yeti then why did you have to radius or shav so much off and also order so many parts?

If you see above, I say that its hard to see how this kit was engineered. It is a kit for the Yeti but at the same time, its more like universal parts that I made that are put into a kit that will work with the Yeti. The knuckles are in fact NOT made for the Yeti, thats why you have to run spacers under the arms to get them to fit the caster blocks. I saw that people were having issues with the shafts and wanted to make them something that they can fix the issue with.

Originally Posted by rob4607

I have seen post stating "if you have RPM arms" you have to shave and radius areas to make it work, to me the guys that are going to spend this much on a front end will most likely already be running rpm arms. And secondly I wouldn't want to modify it to the point I couldn't still be able to use the stock arms in a pinch if there is a part need. I hope this makes sense, I understand some slight filing and massaging but this seems to be some serious removal of material and it would look a lot better removing it at the mill or whatever is being used.

Let me see if I can break this down...

For modifying the RPM arms, I dont sell the arms with the kit and I dont know what arms people will be running. I dont know how to fix this issue. Maybe I should sell modified RPM arms? Would you guys be willing to buy an arm for extra cost that had a dremel taken to the center of it? To me, it seems like 99% would rather just do the work that probably takes 1 minute to save a bit of cash? If not, let me know and I would gladly do it.

I dont think anything was modded to the point where stock stuff wouldnt go back on????

I really think Andrew was being through with his write up. There really isnt much materiel removal that needs to happen. If you look at this picture, it shows very little materiel removal and what I am assuming is more than enough clearance? He also choose to remove from the RPM arm and the knuckle. You could do just the knuckle. Many ways to skin a cat.

Originally Posted by Sapes

Now wether it was designed for stock a arms over RPM?

I have to design around the stock arm. I have to choose something to base it on. If I designed it around the RPM arm, I would get a million emails asking why the stock arm does not fit or issues etc,. Nothing is constant in this hobby, as I think BianaryTerror was trying to explain. I wish it was.

Originally Posted by TM27

Way too much post purchase Engineering in my honest opinion needs to be done to make it even close to usable.

Can you explain what you had to do as far as engineering? It should just be clearancing the knuckles if you want full steering and you dont even need to do that. There should be no engineering unless youre running different parts? If grinding a little bit off the knuckle is a big deal, I can offer to do it for people?

Originally Posted by TM27

The slop in the bearings are terrible . I'm wondering if I have a set that maybe did not get checked ? The front wheels wonder all over the place . Bearings will not even work as designed with this much slop.

Sounds like you didnt install the aluminum spacer between the bearing and the hub? When assembled, the kit is VERY solid with almost no slop. Much more solid than any other setup I know of, by a mile.

Originally Posted by A1Fiddler

The new one has a slight amount of slop in the outer bearing but nothing that concerned me. My front-end seems fine.

If there is ever any bearing slop on any part, a drop of loc tite on the bearing will amaze you.