Just thought I would share a mini-tutorial on replacement of the seat-stay bearings on my Carbine. I noticed that the non-drive side bearing was not rotating smoothly (maybe contributing to the same side bolt backing out – even though loctited) and got some replacement enduro bearings. The hardest part was gathering all the bolts/washers/sleeves/bearings, while the actual replacement took about 15 minutes. The usual disclaimers apply (perform at your own risk, damage may occur, etc) and there are probably better methods out there...just wanted to share my methods.
In general, you want to find washers that are slightly smaller than the opening you need to press through and bolt(s) that fit as snugly as possible in the bearings. The seat-stay bolts are M12x1.75 pitch and the bearings are 6901. M12 bolts are big, so pressing the bearings out with an M12 bolt would have required a specialty washer stack or thin sleeve (slot washer I believe), not readily available. You might be able to stack up the Intense black 3mm washers that come between the upper linkage and the seatstay, but using both at 6mm may not be enough to push out the bearing. A 3-inch long 5/16 inch diameter bolt/washer combo worked fine enough here. The other tough part was finding the right size “receiving sleeve”. This ended up being a 1-inch long section of 1-inch copper pipe tubing, cut straight with a pipe tubing cutter and “de-burred” so it doesn’t mark up the bearing lugs on the seat-stays.
1” copper pipe sleeve – cut to about an inch with pipe cutter and de-burred with file.
3-inch long 5/16” bolt/washers/nut and a 13mm socket
5/8-inch bearing plate (home depot “foundation hardware” section) or other washer stack wider than copper sleeve
4-inch long M12 bolt/washers/nut and 3/4 inch socket
Same 5/8-inch bearing plate and washer stack as above
1) Relieve shock pressure and detach shock from upper rocker link. Remove seat-stay M12 bolts and 3mm black washers, set-aside.
2) Stack several 5/16” washers on 5/16” bolt and insert through bearing from inside out.
3) Place copper sleeve, bearing plate, washer stack, and nut – hand tighten ensuring that the copper sleeve is centered on the bearing lug – so that the bearing doesn’t “hook-up” on anything on its way out. Continually check this during pressing.
4) Use crescent wrench/sockets to tighten the assembly. For me, there was not much force required (maybe 5 ft-lbs or 60 in-lbs). Bearing pops out nicely into the sleeve.
5) With the bearing out, clean the metal lug at the end of the seat-stay, grease both the lug and the new bearing, and prepare the press-in kit. The 4-inch M12 bolt reaches all the way to the other bearing which helps keep the whole press straight. Ensure the bearing plate rests firm and flat against the inside of the lug.
6) Press that new bearing in until snug and confirm there is no gap on the inside of the lug.
7) Repeat other side!
8) In reassembling the upper linkage, use Loctite 243 (oil-resistant, better than blue 242) on the inner threads of the upper link. Using Loctite on the threads of the M12 bolts causes the bolt to be Loctited to the bearing when the bolt is pushed through, which doesn’t make a huge difference performance wise, but makes taking it all apart again most difficult.
9) Go out and ride! Me and my Carbine at D.ville last month.
Downieville Classic Downhill Middle Butcher Intense Carbine - YouTube
Results 1 to 2 of 2