Cup and cone to cartridge: BB
 

Hey, does anyone know if in general, an old style cup and cone BB can be replaced with a modern Shimano style cartridge? The bike in question is an 85 Ross Mt. Hood. I suppose it will depend on how the frame is threaded. Thanks in advance for any responses!

In general, it can. Look at the markings on your current BB. 1.37 in x 24? Is the frame 68mm wide there?
Your Ross probably has 68mm English BB shell. The other number you need to know is the spindle length.
You probably don't have low-profile cranks, and thus have a long spindle from which the cranks attach at near right-angles.
You likely have JIS tapers on your cranks. Sakae? Make sure the new BB has the same taper.
Do your numbers correlate to what you see here? If so, you're in luck. There are more solutions out there as well.

Match the taper, the spindle length and threading...what crank you using?

Except for older Raleighs and older European bikes, almost everthing is English threaded and has been for quite a while and your shell width is very likely to be 68mm. So, yes, your old cup-and-cone bb can be replaced with a cartridge type but, as noted, the spindle length and taper must be compatible with your crank.

This worked fine on my old 1985 Ross Gran Tour.

Thanks guys. Great responses. Yes it's a Sakae CR crank and the shell is 68mm. Can't tell the spindle length without popping the cranks off though. It sounds like Shimano will have me covered.

Should I buy the cartridge and some tools and DIY or should I just put the bike on the waiting list at my LBS for professional wrenching? It does not look too hard to do, but then again - it never does until you're too far into it!

I've done this to all of m older bikes. It's not worth fussing with older BB's. Cartridges are better in every way except that they cost a few bucks extra to replace. But doing so is worth avoiding the frustration and time it takes to properly adjust a cup and cone BB.

It's hard to measure the spindle without at least removing the spindle nuts. It's usually better to completely disassemble everything. One reason is that on the older bikes, the spindle was often asymmetrical. Unless your mechanic is good or you show it specifically to the mechanic, they will give you or install the wrong size. In my experience, I have always needed the a 126-130 mm symmetric spindle, and usually I need to employ a BB spacer to get the right chainline. in general, the older cranks place the chainrings closer to the BB shell than do newer cranks. Sheldon has a great page on this. Make sure to look at the table about Japanese spindle lengths and symmetric equivalents.

http://www.sheldonbrown.com/bbsize.html

I also have a hell of a time getting the fixed cup removed. A good shop can pop them free in 5 minutes and will usually charge only a few bucks for the labor, if anything.

Installing a new cartridge BB is easy to do with the right tools. If you plan to do it more than 2-3 times in your life, it's cheaper to get the tools and DIY, otherwise have the mechanic do it. There is nothing precise about installing the new BB once the threading, size, etc are all matched.

If you do it yourself, pay attention to a couple things.

First, the fixed cup is probably left handed thread and may be difficult to loosen even with a tool designed for it. If you have access to a bench vise, you can usually get a grip on the flats with the vise and then turn the frame in the appropriate direction (clockwise) to loosen it up. Or, you can try the home made fixed cup removal tool that is described on the Sheldon Brown website. Cheaper than a bench vise and probably less likely for Murphy's intervention.

Second, when you go to install the new BB, be careful about threading it in. When you remove the old BB you should find that the cups screw in and out smoothly and with very little torque (once loosened). The new BB should thread in the same. If it starts to get tight before it is threaded home, something is wrong and you need to stop threading, back it out, and fix whatever is wrong. It's possible to screw this up, else there would never be a boogered up BB shell in existence, and there is. Spend a little time with it and if you have a problem threading that you can't solve without force, take it to a well-equipped LBS where they can chase the threads and get it installed properly.

^^As an addition to the above advice, thread it in BY HAND. Ideally you'll thread it in by hand, and then tighten it with the tool. At the very least get it in a minimum of half way before using any tools (that's halfway to seated, not a half thread). If you can't do this, something is wrong. If you force it you'll trash your frame or at least need to get the BB re-threaded as much as possible. Also, don't forget to grease the threads.

It definately will fit. I did the same thing to my '85 Mt. Hood. I don't remember what size I bought though. I had my BB out when I picked it up and my LBS owner walked me through the installation. Fifteen minutes later I left the shop with the new BB installed. Simple to install.

Walt

If the bike had a high quality cup and cone bb this is going to be superior to a Shimano cartridge... these older bottom brackets are worth the "trouble" when you consider how well they were made and how much smoother they are than most cartridges.

Have been cutting open some old cartridge bottom brackets of late comparing build quality and there are some less expensive cartridge units out there that cost less and are better made and even have an Al non drive cup which is less prone to cracking / stripping.

What cartridges have going for them is a low price, ease of installation, and a higher resistance to contamination... consider that a high end cup and cone bottom bracket from days past cost double what a Shimano cartridge bb costs now.

In building up my new old touring bike I changed out my cranks and needed a different bottom bracket... installed an NOS Shimano LX cup and cone and the old Tange bb assembly was still smooth as silk after 23 years and many thousands upon thousands of hard miles.

And there are some really beautiful cartridge bottom brackets out there... they just cost a fair bit more due to their higher quality.

Chasing the threads is something I do whenever I service a bottom bracket... in many cases the factory threads are a little rough or have some corrosion which makes re-installation more difficult. After this removal and service should always be a pretty easy task, as long as you grease those threads.

I tried replacing my Zeus cup and cone BB with a Campy Chorus 10sp and I never could get the fixed cup off. I gave up trying and put the old one back together to leave for another day, and in doing so I regreased and adjusted it so it would be rideable. I was astonished at how smooth it was again and put the Chorus crank on it instead of the old Zeus since both were the same square taper. Now it shifts better too. And to top it off, I found that the one thing about that bike that I didn't like was fixed. It no longer feels mushy going uphill. That is probably the new crank + smoothly adjusted BB. All in all this has been a great 'upgrade', and it was done with stuff I had on-hand at home (including the Chorus crank from a bike I crashed).

OP here, I had my wrench guy at the LBS put in a new cartridge for way less than all the tools alone would have cost to DIM... Back to smooth pedaling and now I can just change it out again and again if needed. There are some much better quality after markets cartridges out there, but I just bought the 27 buck Shimano. All's well. Thanks for the great input brethren and cistern...

+1
I've just replaced an FSA chainset with outboard bearings with a cup and cone Campag Record bb. The difference in smoothness and resistance is astonishing. Their durability is astonishing too if properly maintained.

The bike is a Ross with an SR crank. How good do you think the OEM bottom bracket really is?

Not quite fair to compare a piece of crap FSA bb with a campy record hub. A fair comparison would've been a ceramic FSA bb. But then again - I do get your point. I haven't found a single external BB that allows the crank to spin as well as a loose ball BB or a campy square taper cart.