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Pinion Bearing Issues

And knowing that my outer bearing is inevitable to failure I run the Third bearing as well for backup "thumbsup"

Never thought this way!!! "thumbsup" And you know my opinion, it's not the pinion, but the bearings that fail and destroy the pinion

YES THE XL NEEDS A BOOT
Done this already, both front and rear

"thumbsup"
 
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Finally got some testing in today.

No Shield or cup.


With shield or cup.


The small amount of dirt in last pic is probably due to the dry lube I used on the barrel pin pivot for the driveshaft.
 
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Looks a ton better. As long as the bearing seals hold off that tiny amount of dirt, that should be the fix.
 
Agreed..
I'd much prefer a shield than a trap .. I preferred SteveO's mod
I tried graphite dust and dry lube.. but... no lube no problems
 
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You can try with a 1/8 air filter from nitro engines. You can bond it with the drive shaft and rotate around the rear axle (I wouldn't recommend) or you can bond on the rear axle (or front diff case) and the drive shaft will rotate inside the filter. It won't keep the water away, but you won't have any dust, for sure. I'm pretty happy with my rubber hose mod for the rear, it is much tougher than any sponge. I'm using the air filter only in front, it's not that expose as the rear

Sent from my Sony Xperia Z5
 
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The cup shield has been working great. No failures at all since the shield install and I still check the pinion bearings after every bash session. The grease still gets dirty BUT the bearing doesn't fail any more. Most I have gone is 5 packs on a bash session (out of lipos) and no problems.
 
Hi Steve, I think I may have found a cap similar to the one you are using. Was thinking of the cap for automotive brake cleaners. Although the plastic of your cap seems thicker/better this might be worth a shot. Haven't tried it yet but that was my first thought since they are so readily available. Thoughts?
 
Anything that will keep the crud out so you can keep on bashing. I just used those cups because I had em layin around in a box at work. And they were FREE.
 
Have you tried the HPI 104968 AXLE BOOT 25 X 47 MM, it will need to be zip tied on the axle and some cutting to size when using the plastic rear shaft. No cutting for aftermarket steel shaft, the hump on the wide end presented some problems for me so I cut it, 5 runs with steel shaft so far no bearing failures yet. You also might wanna look at the smaller HPI Racing 86479 Axle Boot 22 x 47 mm, both boots can accommodate 6.5 mm shafts.
 
Here is what I was thinking guys... finally got around to posting a pic
Just a standard cap you find on automotive sprays, degreasers etc
Let me know what you think. I will give it a go sometime this week
Dimensions:
OD 1.3"
ID 1.25"
Depth 1.05"

 
Mine blew out last Thursday after some crazy "watch this!" hill climbs. Totally worth it. (short video soon).

I'm thinking I'll just replace it with the stock housing and try to make some kind of ghetto boot.

Tony, do you have any pics the HPI boot installed? I saw the boot in your YXL Concept thread but I'm sure if that's the HPI mentioned in this thread. How is the 3D printed boot plate you made holding up? Can I order one from you or upload it to shapeways? (BTW, thanks for using a real camera. DoF in your photos is very nice).
 
Here is the RTR with the HPI Racing 86479 Axle Boot 22 x 47 mm, 3 mm smaller and has a tighter grip on the rear axle housing pinion hole, rubber is cuffed at the end no zip ties and it held up after 3 runs and still holding.



The black arrow indicates the end of the pinion hole just below is the cvd ball joint that's where the accordion bellows should be. It will be shortened to about 10 mm starting from the white arrow, I'll silicone seal both ends for some water and mud action this weekend.

 
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Mine blew out last Thursday after some crazy
"watch this!" hill climbs. Totally worth it. (short video soon).


I'm thinking I'll just replace it with the stock housing and try to make some kind of ghetto boot.

Tony, do you have any pics the HPI boot installed? I saw the boot in your
YXL Concept thread but I'm sure if that's the HPI mentioned in this thread.
How is the 3D printed boot plate you made holding up? Can I order one from you or upload it to shapeways? (BTW, thanks for using a real camera. DoF in your photos is very nice).

This is different, the one on the YXL Concept thread is geared towards the use of the WB Drive Shaft AX 31034 plastic shaft, it can also be used with the HR DS which is a tad bigger than the AX 31034. The printed adapter is holding steady, it could be a tighter fit but its screwed on anyways



If you go with the CMT route I can reload the model to shapeway's website and you can order it there just give me a couple of days as I'm redesigning it for screws smaller than M3 or I can upload the original with the M3 screws, you will also need to get this from Ebay. BTW right now shapeways has free shipping so both parts will cost you around $14. From there you can either glue the adapter or drill the AX 31044 to mount it and don't forget to silicone or caulk seal both ends whichever you have laying around the house.
 
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Thanks for tackling this issue! We definitely think in different ways which a great thing as long as we can hear each other out...

So advantages and disadvantages....

Disadvantage:

Dirt could enter through the front of the boot and cause premature bearing failure ...

The boot could act like a funnel for water..

Will the friction cause the fixed boot get wound up in the driveshaft?

Advantages :

The boot is fixed and isn't gonna cause drivetrain vibration... which could lead to premature bearing failure..

Looks awesome!!!

The boot ready exists.... but modifications are needed to accept the boot...


.....hmm can't get past the front of the boot being open to the direction of travel and funneling dirt into the spinning bearings...

Sorry....for thinking out loud... I don't have any experience with Rc boots but in the 1 to 1 world spinning parts cause a vacuum which would tend to cause the boot to get twisted up...
I'd opt for a semi-solid cup that shields from oncoming debris...like Pro Mod Steve's simple,effective boot that doesn't require a adapter or modifications to the housing..
 
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I like the boot idea if a happy medium can be found between sealing at the shaft and not soo tight it twists up and fails. My method is by no means fool proof but it's a start to something better.
 
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