FSA BB Cartridge replacement
 

I posted this question in bike mechanics however, I did not get a response so I thought I would post it here to see if I had more luck.

Thanks to this forum I was able to disassemble my FSA SL-K-light triple. It had been a little noisy and had a little more resistance than what I thought it should. I found the bearing on the drive side not turning at all. Surprisingly the spindle on the non drive side which had the good bearing was discolored.

Question 1. Is the spindle OK to use even though it is discolored? It is not grooved or pitted. Sorry unable to get a photo of the spindle.

Question 2. Will a Ultrega 6700 BB cartridge work fine on this or does the cartridge have to be specific to FSA?

I just went out and saw it has Megaexo BB8681 written on it. Hopefully this will shed some additional light on a replacement.

Easy to get this all over the internet. For example this one on ebay: http://www.ebay.com/itm/FSA-Mega-Exo...item46152525e6

With that easy availability and only $14.99 each delievered, why try to rig a non-specified replacement? I sense you may be thinking the FSA bearing was defective (forgive me if I am wrong) from its failure and a Shimano replacement would be better , but that is not necessarily indicated. If you read hear often, you will see that periodic BB bearing replacement is a common requirement.

Even Shimano's 105-5700 bb would work just fine as I've seen those online for less than $25. Just make sure to grease up the spindle, inner races of the bearings and install the crankset.

Both Shimano and FSA use 24mm axles. If your BB shell is 68mm you should be able to use a Hollowtec II as a replacement.

Thanks for the info folks. Just ordered a 6700 cartridge for it. Will try to post back when I get it installed and let you'll know how it worked.

I didn't think MegaExo was compatible with anything else. I would have just gone with an FSA one. You can order it directly from them.

I am glad you found what your were looking for. Just for general understanding, could you explain why you are so intent on making the change to the Ultegra specific bearing cartridge? In light of the easy availability of the FSA model (which may be identical to the Ultegra, I admit), the generic nature of such replacement cartridges, and the need to order either one, why not just go with the FSA? I'm just wondering what the driving force was for your choice. You seem to have been determined in the selection of the Ultegra.

Mostly price. The best price I found for the FSA was $42 + shipping. I got the Ultregra from Nashbar for Just over $20 due to coupon. I was also already ordering a chain (also Ultregra) and other stuff from Nashbar. Most of my components on the bike are Ultregra and I tend to try to keep the same level of components when possible. I searched thru several posts on the FSA cranks and some folks on here felt FSA is not that great. Don't know if Ultrega is any better. Nashbar did not carry that specific cartridge and I try to use the same vendors I have used in the past and had good results with.

Not to stretch this out, but it is hard to understand what you were trying to do. All that is necessary is to change the single faulty bearing cartridge. Based on the prices you mentioned and the fact you bought from Nashbar, it sounds like you are replacing the whole bottom bracket assembly which wasn't necessary. All you needed was a bearing cartridge for one side, or two if you wanted to be rigorous about preventive maintenance. My point was only that the bearings are not made and branded by the bike parts manufacturer, they are purchased and installed into the cups. There are better and worse brands of bearings, but great bearings can be readily used with any brand of bottom bracket cups. In other words there is no advantage buying the Ultegra name for a bottom bracket. The cups are just a holder for Japansese, or Taiwanese, or German, or at worst Chinese bearings. The FSA cups can hold a "best" bearing cartridge just as well as an Ultegra cup can. If you wanted to upgrade your bottom bracket, all you had to do was spend that money on better bearing cartridges, not on new cups. No big deal. I just wanted you to understand what is going on.

The carbon FSA cranks specify the BB8681 which I understand is slightly narrower than HTII and the MegaExo BB specified for the non-carbon FSA cranks. The effect of not using this specific BB is potentially too much bearing load with crank bolt torqued to spec. You might also have difficulty getting the crank spindle to fit the HTII BB as although both nominally 24mm, the FSA spindle is marginally bigger than Shimano's. I'd be interested to know how you get on with the Ultegra BB as they're cheaper and easier to get hold of than BB8681s.

Yeah, but he doesn't need the while thing, just the bearings. Those are easy to find.

UPDATE!

First, thanks for the info Rpenmanparker concerning bearing selection. What kind of specialty tools if any would I need to replace the bearings in the housing?

Ordered the 6700 for less than $25 and installed. The 6700 BB was definately tighter on the spindle than the 8681 BB. Had to tap it with the palm of my hand to get it on. Once assembled the crank was definately tougher to turn. If I tried to spin it it would maybe only go 1 revolution. I then checked out the instructions and noticed if it was going on a triple (which it is) I needed a ring and spacer which typically comes with the crank.

I have not got a chance to troubleshoot it so I am not sure if it is tougher to turn due to being tighter on the spindle or if it is due to assembling without the spacer. Any thoughts? Also where might I get the ring and spacer, direct from FSA?

Go to the FSA website. There is somewhere on it a replacement parts section. Just make sure you have the right model selected. Their site can be confusing. And while the parts aren't terribly expensive, their shipping is.

According to posts on other sites I have found, you first remove the caps from the outside of the cartridges. They often break when you try to get them out so it is helpful to buy some spares along with the cartridges. Then secure the cup in a vise (cushioned with wood blocks to protect the cup) and punch out the cartridge from behind. One recommendation I saw was to use an old 27.2 mm seat post as the punch and a rubber mallet to provide the impact. One source says to use the mallet to hammer the new cartridge into the cup and replace the cover, but I think a vise with cushioned faces or a big C clamp with wood blocks would make a good press for getting the cartridge in.

I don't see why you couldn't remove one cup from the frame and use the frame as your "vise" to hold the second cup. Run your punch through the BB shell to knock out the cartridge from behind. Then use the C clamp to press the new cartridge in while facing the cartridge and the opposite side of the BB shell with wood blocks. When done on the one side, take out that cup and replace the other one to service it. Then reinstall the cup you serviced first. A vise shouldn't be necessary.

Edit: After further looking, I am wondering whether the Park tools for BB90, BB86, etc. wouldn't work just as well for removing and replacing cartridges in threaded cups. See here: http://www.parktool.com/product/pres...l-set-bbt-90-3 and t buy it: http://www.ebay.com/itm/Park-Tool-BB...item5d40011bf7

The punch tool should work fine. I imagine the press adapters would work okay too. You just need a homemade or simple purchased press. These are all over ebay or can be made from a threaded rod, appropriate nuts and large washers. Here is one on ebay that looks pretty good: http://www.ebay.com/itm/BB24-Bottom-...item3ccfdd4e2a

Went to FSA website and after considerable navigating did find some spacers and washers listed. However, based on their website I was unsure which ones I needed. Called the tech line and the tech was not helpful saying that you could not use the 6700 in place of the MegaExo. Obviously MegaExo is what they sell. I called the most helpful LBS in this area and they don't mess with FSA cranks so he was unsure which ones I needed.

Any ideas which direction to go from here? Any idea which washer and spacer I would need from the FSA website?

One thought for you to get expert advice is to PM #campag4life . He is one of the most knowledgeable gurus re: such things. Unfortunately I have not seen any trace of him on this forum for a few months. I can only hope he is just taking a short break from the rest of us and will be back soon. In any case he may respond to a PM.

If there is anything I can still offer you of any value, it may be this. I fully recognize this may be advice you don't want to hear, but at this point if I were you, I would punt. Sell the Ultegra BB you bought and buy the full Mega Exo set of cups. I now realize that after all is said and done the bearing cartridge replacement may be more trouble than it is worth. Just go with the like-branded OEM replacement of the whole BB. You should get most of your money back for the Ultegra.

Here's my $2c.

You're supposed to use BB8681 with FSA carbon cranks: it's different from the normal FSA mega exo BB and different from the Shimano ones. I picked up a BB8681 a few months ago and it came with a spacer, but I understood that to be for MTB frames. From what I'm reading now, FSA triples do not need a spacer, but my double FSA SLK does use a wavy washer on the non-drive side.

I've never had an external BB, whether Shimano Tiagra, 105, Ultegra, FSA, that did not have some bearing friction when installed correctly, i.e. the crank arms do not spin as freely as you see with square taper BBs so stopping after 1 revolution is not unusual IME. They do loosen up a little in use, but the drag is not a concern when riding.

If I were you, I'd run with the Ultegra BB you have now if you've installed the crank to the correct torque spec and:
there is no lateral movement of the crank through the frame
there is no play at the bearings when you move the crank arms from side to side
the cranks spin smoothly on the BB (not necessarily free running)
the crank arms to appear to be the correct distance from the chain stays and do not hit them
shifting at the front appears to work as before without huge adjustment of the FD

I don't see how you can really have a serious problem with this BB if it appears to work correctly as determined by the above. It may not last as long as it should, but you'll do no harm to your frame or crank and you should get at least 1000-2000 miles from it.

Otherwise, pony up for a replacement BB8681.

Replacing bearings seems like too much hassle if you don't have the correct tools to remove and install them in the cups.

I agree with everything else you said, but don't quite know what you mean by this. All of my FSA carbon cranks (SL-K Light) for use with outboard mounted bearings (screw threads into a BSA BB) came with Mega Exo BBs. What do you mean that the BB8681 is supposed to be used. Mega Exo is clearly specified in all the FSA literature. Thanks for clarifying this.

Basically there are different types of Mega Exo BB specified for different types of crank. The carbon ones (SLK light, K-Force light) should be using BB8681 or BB8200 (ceramic)). It's hard to find the relevant literature on the current FSA website, but this old document sums it up:
http://www.bike-components.de/bedien...structions.pdf

Some other info here shows that BB8681 is for the carbon cranks and BB6200 (was BB6000) for the alloy cranks
http://www.fullspeedahead.com/storag...-chart-web.pdf

Found this post too which states that the bearings are 6mm wide in the BBs for the carbon cranks to allow room for the wavy washer as opposed to 7mm in Shimano BBs.
http://www.bikeforums.net/showthread...=1#post8412886

Seems then that a Shimano BB would possibly be OK without the wavy washer, but the bearing load is going to be hit or miss.

Bobones, thanks for digging up those threads. I will probably run by another LBS and pick there brains and see if they can come up with any ideas. If I do find a way to get it to work I will post it here. In hindsight I should have just gone back with another BB8681. < $30 lesson learned.