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Pinion Bearing Issues

You do need shims for the third bearing. How many depends on what type of pinion you have. Check my thread and, if you have any question, please ask. Unfortunately, not even version 1.000.000.000 of any new housing will resolve the bearing issue. The problem is the bearing itself, not the housing. It is severe undersized for the job and, since no dedicated producer manufacture this specific size (Skf, Koyo, etc), we are stuck with toy-grade bearings. Well, maybe Boca has some $80 ceramic bearings, but I'm curious how many people are ready to spend this kind of money.

Sent from my Sony Xperia Z5
 
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I second the 3rd pinion mod. It creates a much beefier rolling mechanism. I also agree that the issue is the size of bearing we are limited to. A lot of the bearings on this beast should be much bigger for the size and ability this thing has. What I will say is that if there was a magical $80 bearing that would fix this Achilles heel I would spend the money in an instant.
 
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The third bearing is great ..It protects the pinion from catastrophic disaster from the outer pinion blowing from (Dirt) .. Its not a fix for the HD gear but is important to do to prevent pinion/ring gear carnage .. The true fix is protection the outer bearing..I run a vanquish which is a big advantage mainly because of the 24mmX5 compared to the 21mmx4mm bearing also less shimming is required for the 3rd bearing.. But the outer bearing still fails..I think pro mod Steve's deflector is the cheapest most effective option along with the 3rd bearing.. Harley contacted me about the V2 and it sounded like he was considering a boot.. Time will tell.. But I think a stock axle with modded HD gears with the 3rd bearing , quality bearings and a deflector is all any true basher needs..
BTW I do intend on trying a bushing... surprised no one has yet...
 
I second the 3rd pinion mod. It creates a much beefier rolling mechanism. I also agree that the issue is the size of bearing we are limited to. A lot of the bearings on this beast should be much bigger for the size and ability this thing has. What I will say is that if there was a magical $80 beating that would fix this Achilles heel I would spend the money in an instant.

The main advantage using three bearings is that you distribute the forces, more or less equal, to all three of them hence less forces on each of them. Beside this, if you are lazy enough and you don't change them when you should and one of them is failing (usually the outer one), it is not as catastrophic as when you are using only two.
I'm not very sure a $90 ceramic bearing (not $80 :lmao:) is what you need. They do have some qualities, not sure those qualities are needed here. Maybe a regular $25 stainless or a $18 chrome bearing is better. Nevertheless, me personally I'm not interested in spending that amount of money. I prefer using cheaper bearings with this mod, check them every 10-15 hours of running time and change what and when is needed
 
a vanquish ... is a big advantage mainly because of the 24mmX5 compared to the 21mmx4mm bearing ... But I think a stock axle with modded HD gears with the 3rd bearing , quality bearings and a deflector is all any true basher needs..
BTW I do intend on trying a bushing... surprised no one has yet...

You are absolutely right!! The only amendment is you don't need your mod, since you need to remove the original spacer anyway and add some shims. Removing that edge means more shims.
I was thinking using a bushing, but I have two problems: my turner is on vacation and I don't know what king of brass I should use. I suppose a very hard one. Probably I will google to find out what... However I consider it will be a GREAT problem lubricating a bushing, since you'll not have any kind of protection against the dust. But, even so, you will not have any catastrophic failures anymore
 
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You are absolutely right!! The only amendment is you don't need your mod, since you need to remove the original spacer anyway and add some shims. Removing that edge means more shims.
I was thinking using a bushing, but I have two problems: my turner is on vacation and I don't know what king of brass I should use. I suppose a very hard one. Probably I will google to find out what... However I consider it will be a GREAT problem lubricating a bushing, since you'll not have any kind of protection against the dust. But, even so, you will not have any catastrophic failures anymore

after countless times going over and over about BHB's HD gear mod one would think you understand what is actually happening. The material that gets removed is post shims, meaning it pushes the pinion out beyond the bearings and shims. The shims just eat up the slop in the bearing area not add overall length. The haunch that gets removed shortens the reach of the pinion into the gear mesh
 
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I was talking with Lockup RC about a bushing. I had asked them about making their Black Ice bushing in a larger size but there was issue with the materials (I'll look through my PMs later). He did mention that they may be testing a larger size in the future. I'll ping him for a status update.

It's a issue on vehicles that use AR60 axles. Dlux makes an AR60 housing with a larger bearing and the F9 I just put on the Bomber has a giant bearing. I don't think it's realized as often as it with the YZXL. True crawlers don't get the abuse the YXL does. I don't read the 1/10 Yeti forums but it's a "go fast" with an AR60. I never had an issue with my bomber stock. I broke the housing jumping, but not bearing wear.
 
I rebuilt the rear axle...again.

This time I did 3 bearings and a few shims. I also put the HPI boot on the drive shaft. It doesn't fit well on the stock drive shaft, but at least it provides some protection. It actually looks pretty cool. I'll take a photo of it when I get home.

I was looking at the SuperShafty site today and they have a thrust mod for AR60s. I sent them an email regarding the YXL and linked this thread.

AR60 THRUST WASHER MOD - Super Shafty
 
I used this type of bearing on my Losi XXL transmission instead of the original plastic crap. And this is the type of bearing it might make bushing mod work. Unfortunately, on a quick google search, there is no thrust bearing with the needed dimensions. Closest is 15x28 :(
 
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I forgot to take a photo of the boot.

I drove the YXL a bit in the front yard and park next door last Sunday. It was funny because my daughter was driving a little 1/24 truck I got her for Christmas and would drive it under the YXL and laugh. When I punched the YXL she ran away...so funny. I asked her why she hates on the YXL. "I don't hate it, I just don't like it near me." Hopefully she feels that way about boys for the next 100 years.

Anyway, everything seemed to hold up with the very pussified driving I was doing. The heat that gets generated on that pinion output worries me though. It's noticeable after a few passes at full throttle on 6s. Thursday I'll give it some more serious testing.
 
I didn't post pics because the bearing failed with the boot. Then Crawlapollooza took some time. I was pissed I didn't get to take the YXL to Crawlapollooza.

There was a guy doing some hill runs and bashing with a YXL on Saturday at Crawlapollooza. I commented to my buddies that I bet he blows the rear bearing. After a few runs I noticed the guy messing around with the rear axle then carry the YXL off /doh.

I really have no desire to mess with the YXL for a while. It's such a stupid ass RC. I used to love it now I just want to kick it every time I see it. I'm going to start calling by my ex-wife's name. I hate it that much right now.

My hate will fade and I'll give it another go. RCs are so much better than women, I can't stay mad at them long.
 
When your hate will eventually fade, try and do the third bearing mod. You will love your rig again, I promise you

Sent from my Sony Xperia Z5
 
I'm going to try a boot on mine since I just had a blow out.

Otherwise, there's always the Kraken Vekta...
 
For what it's worth. I had several sessions in sand, and found sand inside of my gear box, but no sand on/in the bearing that sits on the outside of the pinion. Not using a boot.
 
Sure you can. Upload on photo bucket, get the direct link and under a new post click the img tag and paste the link. Thats it.
 
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Sent from my iPad using Tapatalk Pro
 
Nice job Brinkman BUT keep in mind this is NOT a fix all. I pull the rear pinion after every bash session or 4 packs (only have 8 3S now) and the pinion bearings are still dirty but not failing. Since the mod and pulling pinion every 4 packs all is good.
 
Does that orange cap just ride tightly on the HD DS without glue etc.? How is it secured? Any reason why you didn't try the HPI rubber boot?
 
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