21 January 2016

Replace Sram GXP 121mm pressfit fat bike bottom Bracket & making a bb press tool

Well after a few years of use the bearing on the drive side had gone on Krampgrease. I stripped it all down and the non drive side bearing is like new and nothing wrong with the bb cups/sleeve & caps etc just the bearing.
I did not have a replacement bearing to hand but did have a couple of spare bb's so popped a complete new bb in. I have kept all the old parts and will have a look for some replacement aftermarket bearings.
I have the same bb fitted on the Beargrease and that is still ok and is a year older but does less miles than the Krampgrease.
You don't need many tools to swap the bb - 8mm allen key to remove non drive side crank arm. Then a Park tool BBT-90.3 Press fit removal tool but I have seen other people use sockets etc. Once out cleaned the bb shell and applied fresh grease, greased up the new bb and gently pressed it into the shell just so it was in place.
I then have the press cups from the BBT-90.3 set but problem is they don't fit onto my Xtools press so I had a plan.
Looking at the HHP-3 press I decided to make my own from the following items, which is enough to make four really with nuts/washers left over -
M12 threaded bar £2.58 for 1m = 1no x 250mm = 64p
M12 Penny Washer £0.81 for 10no = 2no 16p
M12 nuts £2.94 for 50no = 2no 11p

That makes the press 91p and I will probably reuse the left over materials in years to come.
It worked like a dream and great value for money! Once pressed in cleaned off the excess grease. Slide the wave washer and spacer on the drive side crank spindle, slide it through and fitted the non drive crank arm and nipped it up and she's ready to rock and role again.

Trying out my new allen keys - oh they are lovely. This is a 10mm, its a 8mm you need to remove crank

cranks and ready to be cleaned

old bb out and drive side bearing pressed out and cleaned

new bb getting pressed in

new bar not cut down yet, checking to see if it was going to work ok first

and it did

so I cut it down and grinded the cut end on my bench grinder


not quite the same quality as my X-Tools one

where can I get some of these from?




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