Rear wheel loose bearings on mso

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tysons_201

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noticed on my bike today that if i grab the wheel i can move it sideways and the movement is coming from the bearing area. The bearings arent wrecked its like the wheel isnt done up tight enough to hold the bearings in place or the part which holds the bearings in place has expanded allowing it to move up and down. This place is the same spot that broke on my last wheel where the bearings sit inside the hub. I also noticed that my axle is bent again.
Does anyone know how to fix this or do i need a stronger wheel?
 
I have worked out the problem, and i think i know the cause.
Because of the weak axles supplied with these bikes, the axle ends up bending fairly quickly and it bends at the bearing area causing along of pressure of the bearings and bearing housing on the hub. The bearings are meant to sit tightly in the hub but when the axle bends and the pressure of the bearing causes the bearings to spin inside the hub causing it to wear out the hub which ends up making the bearings sit loosely instead of tightly inside the hub.
The only fix for me is to buy a bigger bearing with a larger outside diameter and get a stronger axle to prevent further damage. Or i could somehow wrap the bearing in something so it sits tightly in the hub but this would be hard as there is not even 1mm gap inbetween the hub and the bearing as its not worn out much(just enough for the wheel to move noticably when you move it).
Any suggestions?
 
I wouldn't have thought the axle would bend unless it's been loose... I'd suggest getting a new wheel and axle, and tighten the nut up as tight as possible, and check it after each ride...

The amount the wheels are worth it's realy not worth stuffing around with the shagged out wheel, no matter what you do it's unlikely to last long....

Might be worth buying a high tensile bolt/axle from your local bolt supplier, just look up "Bolt & Nut" in the Yellow Pages, Coventry Fasteners is one of the better ones..

Goodluck..
 
yeah spoke with Linda from MSO today and she notified me that it is a problem with the bearings in the wheel which is causing them to break. They should have the problems sorted soon.
I am going to be getting a new wheel with 15mm high tensile axle and should fix the problem.
 
I swapped out front and rear with quality Jap bearings as soon as I got it and have had no problem.
 
Have you checked the rear axle for bending? do you jump the bike?
I only do very small jumps and the axle has bent on the sprocket side.
 
Yep...I checked the axle and it's not bent. I'm gonna chuck in higher tensile axles anyway. Maybe your chain is overtightened? I haven't gotten any serious air yet...
 
thinking about gettin a new wheel with 15mm axle. But the only problem is the slot in the swingarm is only big enough for a 12mm axle. Was just gunna drill it out bigger.
Chain wasnt overtightened its stretched and always comes loose straight away. Need a new high quality chain too.
 
Ive had the same problem, Ive had my bike for about a month and Ive bent 4 axles including a machined stonger axle I got made. I'm currently changine the back to 15mm axle and making better adjusters.
 
have you damaged any hubs? what sort of bike do you have?
Let me know how you go about swapping the 12mm for a 15mm and what you had to change.
 
i BROKE THE HUB. I have an AGB29. I ordered a new complete wheel with better hub and 15mm bearings cost around $150 inc freight. have to get different sprocket and modify the disc. Will hopefully fit it all tonight. will let you know how it goes.(I was jumping a full size FMX ramp at 30ft at night, It loved it)
 
yeah i've already broke 1 hub and bent 2 axles. The other hub is on its way out as theres a fair bit of bearing movement in the hub itself. Hoping all my sprocket and disk will fit on the new wheel with 15mm axle i will be buying soon off ebay.
 
What bike do you have and were r u getting your wheel from
 
Seems we lost a days worth of posts in the move so I'll repost what I said earlier....

Lot's of big bikes only run 12mm axles and don't have these problems... the only design fault I can think of that could cause these bikes to be prone to axle bending is if the chain tightens heaps as the suspension is compressed, or the locknuts are crap and the axle is comming loose...

If this is a common problem with these bikes and not a result of operator error, I'd be getting the supplier to replace the parts free of charge...

Keep in mind if you change to 15mm axles you'll have to get your forks and swingarm machined out (your asking for trouble if you just file them out), and replace your chain adjusters and rear brake caliper plate/mount....

I recon you should just get a good quality replacement 8.8 high tensile bolt/axle and locknut from a bolt supplier, and good quality bearings, and put them in new wheels...
 
Its not that bigger job to change to 15mm rear hub, you dont need to change the front hub(mine has not bent). all Ive done is digrinded the swingarm so the axle fits threw and got a different rear wheel. I think the problem is in the fact that there is a lot of un supported axle between the sproket and swing arm. My big bike has like 30mm at the most and the axle is 3 times thicker. I had a high tensile axle machined up and it bent just as quick.
 
I assume you have the spacer in there??

15axle.jpg
 
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yep, They just hold the wheel in the right spot. They dont stop the axle from bending. It all depends want your doing with your bike to how serious you get. I m putting the 15mm axle in so i can jump bigger and ride harder.
 
Finished the conversion last night test it out tomorrow, It seems ok.
 
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Carefull it doesn't all rattle loose... Just need lock washers and/or loctite on the sprocket bolts and loctite on the disk screws.... Would be worth getting a good quality locknut for your axle also..

Edit: was the disk a good fit on the new hub? The cap screws through the disk look like they they're off center, and not sitting snugly into the disk... if so it's likely to cause problems like shuddering and vibrations...
 
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