Rear Suspension Bearing Replacement
Anyone replace the bearings on their KHS yet? After deciding it's time to service the thing, I took apart the rear triangle with intent to clean and regrease (if needed). Most of the bearings were siezed or rough so I'm in the process of replacing (just put in the order for equivalent bearings from bearingsdirect.com - about $30 all told, including shipping).
I'm wondering, has anyone tried the MAX bearings from enduro seals? Basically a cagelss bearing with more balls to increase surface area and hopefully, longetivity. They only make two of the sizes, but the other is a small size, one I'm thinking sees lower load and didn't seem to feel as rough as the others. Or does anyone have a supplier for bearings with equivalent sizes but higher load ratings? (i.e. equivalent needle bearings or non-caged bearings?)
Has anyone seen different results from their suspension components? Any longer lasting bearings? Anyone had any success with bushings?
I've never changed bearings, but am interested in how your swap goes. Here's a thread bump and let us know what you end up doing.
Just got new bearings yesterday - will be doing the swap later today. The new bearings are the same specification as the old bearings (caged, shielded, deep groove, radial, ball-bearings).
I'm a little dissappointed with KHS for what appear to be undersized bearings and for using three different sized bearings when they all could have been made the same size.
I've had the frame for about a year - I tried to avoid hosing the thing down to discourage corrosion (the bearings and pivots are shielded well enough that dust isn't a problem). Seems like the couple of rides in the wet can be enough to displace the lubrication in the bearings. The stock bearings are really rough and require a lot of encouragement to turn a full 360 degrees. I'm sure that I'll be destroying them to get them out (the stepped design on the linkages is kind of a bummer, too) so I'll be able to check for pitting and/or galling. I'll also check to see if they're dry or still lubed.
I'm torn about pulling the shields off the new bearings and repacking with better grease. Seems like the stock stuff is a litte on the thin side but, at twenty bucks a year, seems like it might be a worthwhile experiment to see if the stock lube holds up - maybe dissasemble in 6 months and check.
More to come.
So - finally got all the bearings back in. I initially ordered the wrong ones for the seat-stay section - got 609-2RS instead of 608-2RS. This is good new as it means that the MAX bearings I originally wanted to get as replacements, are available for all sizes. I held off on the MAX bearings - enduro seals sells these - because I thought I needed the 608 size which was not available. The writing on the bearing shield is easily hidden by dirt. The full contingent of radial ball bearings for the XC-204 is as follows:
To get the bearings out, you need an arbor press (bench vise might work instead), an insert that will fit in the small diameter of the counterbore used to thread an axle through the bearings (I think about 12mm or 1/2 inche should be spot on), and a cup (or washer or nut - something sturdy that's deeper than the bearing) that's larger than the outer diameter of the biggest bearing (but not by much, 30mm should be a good match). Stack all three of those things together and press the bearings out (keep track of what goes where, two have the same outer diameter). Use the old bearing to press in the new ones (so you're pressing on the outer race instead of just the inner race and the shield). When you reassemble, after pressing everything in, give the shields and metal bits a healthy coat of grease. Tighten stuff as tight as you want when you tightening a fastener contacting an inner race on the bearings (that's a nice little bit of designwork - the width stackup on the axles is used to ensure that the inner race is moving relative to the outer race, rather than the axle moving relative to the inner race). I had to use a lower torque on the rocker arm to air can bolt/axle assembly otherwise binding resulted. It looks like the same use of width stackup design work was not used for the air can interface.
The bearings I removed ranged from not too bad (one still had a little bit of grease inside), to almost completely siezed (one moved about 10 degrees). In an earlier post, I'd said that the bearings looked undersized - I don't think that was the case. I do think that alignment challenges may have warranted a different bearing type (maybe two angular contact bearings?) and/or may have resulted in the primary deterioration of the bearings. After I pressed them out, most were able to provide full range of motion with relatively little grinding. The side load used to press them out may have broken free any corrosion that was present prior to removal. I certainly wasn't getting full ROM prior to removal on any of them.
Reassembly has resulted in much smoother motion. I have yet to ride to see if the difference is noticeable in the saddle.
I've been wondering about mine lately as it seems like the rear is getting a little jumpy over bumps. I'll pull the shock to see how it feels and may do the bearings this winter anyway.
Thanks for the info on the sizes.
No Problem on the sizes. You'd have seen them yourself when you took things apart (of course, you might have problems telling the difference between an 8 and a 9 ).
Finally got everything back together completely and went for a quick spin around the block last night. Suspension seems a lot plusher and more sensitive than before. Could also be that I've been riding my road bike for the past week though.
The cost on the bearings from bearingsdirect.com was around $25-$30 (with shipping). If I were to do this again, I'd give the enduroseals MAX bearings a go - partly because I think the grease in them will be a bit thicker and better suited toward harsh environments (as opposed to thin for dealing with high rotation speeds), and partly because I think they'll last a bit longer (most of the corrosion I saw was on the cages, which I think ends up breaking off and inhibiting motion). Also, the price is about the same, maybe slightly higher for the MAX bearings. If you get regular bearings, make sure you get rubber sealed bearings, not shielded bearings.
are the part numbers and prices around the same for the Enduroseals? I've read a lot of good things about their bearings.
The number I listed above can be used to identify the EnduroSeals equivalent bearing.
I just got back from riding in Sedona, AZ and I've got to say, the new bearings make things buttery smooth. The suspension feels a lot more squishier (presumably since there's less compression damping in the entire system), to the point where I'm running the shock about 10psi higher than I normally run. This seems like it keeps the rear tire in better contact with the ground, and adds a bit of stiffness when climbing. Yeehaw.
In summary, if you're thinking it might be time to service the suspension system, consider ponying up the $30 for new bearings - it makes a helluva difference.
Good to hear