Bicycle Mechanics - bearing size for hub

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View Full Version : bearing size for hub


hugging corners
02-11-11, 12:01 PM
hello
my bearing in the hub gave up
i need help to determine the size, and i have looked around and cant find info.

it is Schwinn road bike
700x25 wheel
suntour gpx hub
it has quick wheel release mechanism
look like this http://cgi.ebay.com/NOS-Suntour-GPX-Hubset-36-Hole-w-126-mm-Spacing-/270613078785?pt=Cycling_Parts_Accessories&hash=item3f01cbe301

can someone help me with size, and are there special tool needed to remove it?
thanx H/C


bikeman715
02-11-11, 12:44 PM
You need 18 bearing in the 1/4 " for the rear. (9 balls per side ). For the front you need 20 3/16" bearing ( 10 balls per side). You need a 13 MM (for the front )& 15 MM (for the rear ) cone wrenches. A box wrench in 17 MM will work for the locking nuts. You can use the cone wrench to remove any seals in the hubs to get to the bearing.

hugging corners
02-11-11, 02:17 PM
Thanx for this POWER HINT. all the numbers i needed
Thank you H/C


hugging corners
02-11-11, 03:21 PM
i hate to make it more complicated but have more questions
http://cgi.ebay.com/2-Bicycle-Bearings-Model-27-3-Piece-BB-Crank-9x1-4-/200570451151?pt=Cycling_Parts_Accessories&hash=item2eb2ee34cf

so that would be back rim,
i bike about 20 miles a day (race it in traffic)
are there any stronger (like sealed) bearing available for this hub
I've also seen ceramic bearings, could not find relative size- are these any good or do they come 9 x1/4

quote rear 18, front 20 - what these numbers represent


thanxH/C

HillRider
02-11-11, 03:27 PM
You need loose bearing balls in the number and size bikeman715 posted. Try to find Grade 25 balls.

There are hubs that use sealed cartridge bearings but these aren't them.

Yes, you can buy individual ceramic bearing balls in the required sizes and substitute them for the steel bearings but at much higher cost and with negligibly tiny benefits.

davidad
02-11-11, 07:02 PM
I have Suntour XC 9000 front hubs and they use 6001 2RS radial bearings(cartridge bearings). If yours are conventional cup and cone hubs then the front will use 20 3/16" balls and the back will need 18 1/4" balls. Grade 25C is overkill but not too much more expensive than the grade 200's. Ceramic bearings are necessary in very high seep applications where there can be high heat like a cars turbo charger turning 100,000 rpm.
Your hubs will be flying along at 168rpm at 15mph.
I overhaul every 2500 to 3000 miles and my hubs are over 10 years old and going strong.