canklecat

I never felt any need to update an old school square taper, caged bearing bottom bracket with any other bike. But my early 1990s Univega Via Carisma needs frequent attention to snug up the BB and it's getting annoying.

Best I can figure, the very thing that makes the Via Carisma comfy on chipseal and rough stuff -- springy yet responsive Bi-Axial Power Oval chromoly steel frame -- also makes the BB lock rings loosen every few months. I can tweak the non-drive side without pulling the crank, but I can't reach the drive side bits and bobs without pulling the crank and triple chainring. If I could it'd be less annoying.

So, whattaya think... Shimano's entry level UN55 cartridge BB? Or have y'all found others that work as well or better?

BTW, yup, I've chased down every other possible source for creaking. This has been an ongoing challenge since I got the bike three years ago. I usually do the BB last, after eliminating other possible sources for creaking and squeaking:

• Last time it was the black enamel/painted spokes on the rear wheel, creaking from friction where they crossed. Easy fix with a few spoke adjustments and soft paraffin at the friction points. But that didn't work this time.
• I've replaced the chain. Same KMC Z72 I like for most bikes. I got three years and several thousand miles from the last chain. New chain didn't fix the creaking.
• Swapped rear wheels. Didn't help. (That's how I identified squeaky spokes as a source last year.)
• Replaced the 3 year old cheap pedals. No help.
• Checked crank arm tightness. No help.
• Checked chainring bolts. No help.
• Snugged down left/non-drive-side cup and lock ring. That helped a little. There's still a tiny bit of play on the right/drive side, but I'll need to pull the crank arm/chainrings to fix it. And it'll be temporary, again.

JaccoW

I have something similar going on but mine has plastic cups because the steel-cupped one I brought was too narrow for a triple setup.
Bike shop replaced them with a longer one they had in stock... with plastic cups. It is now creaking after a year.

Shimano seems to be a popular well-regarded choice. Besides, many of the alternatives are either much more expensive or very hard to come by.

What crank are you using?

jcb3

+1 on the UN55.

I initially got a 127 for a shimano 62xx triple, but it was too wide - 124 was better

Classtime 

If there is play on the drive side crank, there is play on the nds also. There is no adjusting done on the ds. If you tighten the fixed cup sufficiently, it won't loosen. In my experience, that goes for Italian and French threads too but double up on the torq. The UN 5_ work fine but they are consumable and annoy me because of that.

Spaghetti Legs 

I would call the UN55 mid-level rather than entry level and it is a good BB for the money. If you can’t get your current BB to tighten down adequately without any play, the threads in the shell might need to be chased, or at least cleaned up well. You might also try blue Loctite (241 or 243 I believe) to keep the cups from loosening up.

Reynolds 531 

Actually face the backside of the lockrings, if you were considering keeping the old BB. Of course, your idea to change out the BB for Shimano is the best choice.

canklecat

Shimano Exage, 110 ,
bcd with 50/40/30 triple.

Road Fan

Canklecat,

High level:

I think you have eliminated everything but the BB mechanicals themselves. I would work more to evaluate my existing BB before replacing it. Usually these have the fit the OEM thought was perfect, and decades of durability left with maintenance. In the overhaul process I'd evaluate the condition and then either clean and rebuild or discard and replace. The replacement might not fit as well, and unless torqued correctly might not remain tight, leading to wearout or at least more creaking, so you'll have to consider this. As a replacement a UN55 is a decent quality and cost-effective part, but it might not position your crank arms optimally. For this bike I'd say optimally means to put the crank arms (and chainrings of course) at the same distance from the frame center as they are now. Discrete spindles were often chosen with the left NDS stub at a different length from the right DS stub. I don't know if this is the case with your bike, but most UN55s and nearly all other integrated BBs have symmetrical stub lengths (Token, Tange, IRD, et cetera). This might or might not concern you. Using a recommendation your buds here give you will almost for sure give you adequate clearance to the chainstays and prevent your crank arm from beating holes in your chainstays. But it might not give you the same pedal to pedal spacing ("Q factor" or "tread") or the same chainline. The objective need for both factors to be correct is controversial (almost as bad as chain lube), so it's just a matter of what floats your boat.

I think your continual need to snug the lockring is a sign your cups and spindles at least need adjusting to help the BB remain stable in that flexy frame. In the vintage literature there are a lot of good instructions on how to handle this - not special for flexy steel, but pertinent since nearly all vintage 531db frames are what we now see as flexy. The old Anybody's Bike Book by Tom Cuthbertson (I have the edition from 1971) is what I'd recommend. Because of the flexiness of your frame, it's probably extra-important to have the lockring and the fixed cup tight, to prevent the old BB from wearing out and to keep it running play-free. If after all this the spindle is rough and cannot be smoothed by adjustment, you may have a worn-out BB where something needs replacement. So it needs to be disassembled and cleaned, inspected for wear and the bad stuff renewed. At this point you need the UN55 or to find NOS parts.

Deeper level: find the Tom Cuthbertson book for good practical adjustment instructions that are now as useful as they were then. He also has good advice for the minimum level of special tooling you will need, at least for you original BB.

canklecat

Thanks, all. I think part of the problem is those dinky mating surfaces for wrenching the lock rings tight. They defy efforts to snug 'em down properly. Thin wrenches are okay for hub cones but terrible for anything that demands serious torque. Looks like the later splined rings and tools solved that particular problem.

Maybe I'll try thread locking compound, although mechanics differ on whether this is appropriate for bottom brackets. Same with chainring bolts -- nobody seems to agree on whether to use thread locker, grease or leave 'em dry.

I'm reluctant to use thread locker on the original lockrings for the same reason: the existing tools -- hooked Hozan "Rock Ring" wrench and thin cup wrenches -- are already a terrible design for serious torque anyway. It would be a nightmare to try to remove threaded fasteners jammed by thread locker with those inadequate tools.
@Road Fan: Roger that, the chainline consideration and Q-factor -- with aging knees I'd rather keep everything lined up as well as possible. And Cuthbertson's book. I had his book as a teenager back in the 1970s. Lost track of it somewhere along the way. I might buy another just for nostalgia... and the solid advice.

63rickert

This is why you go to an LBS that owns a Campy tool case. Or VAR tools. Send that fixed cup home with a big two-handled driver. DIY home tools are not sufficient for fixed cups and never were. While they are at it have them face the BB.

If I lived some place with no quality LBS and didn't want to search out shop quality vintage tools online - and pay for them and pay again to have them sharpened - I might give up and use a cartridge of some type.

The lock ring will work better if BB shell is faced. My usual when in a quandary about lube or locker is beeswax. When threadlocker makes removal difficult use heat. Heat softens/breaks down any Loctite product. Getting heat where needed is sometimes hard, it will always work. And if you just like threadlocker, Loctite Purple low strength is best for small threads, aluminum parts, most bike applications.

JohnDThompson 

Have you tried a lockring pliers rather than the hooked spanner? The official lockring pliers from e.g. VAR or Hozan tend to be expensive, but it's fairly trivial to fabricate a functional copy from a set of slip-jaw pliers:


https://www.instructables.com/id/DIY-Lockring-Pliers/

TiHabanero

Back in the day we ran into this quite often on aluminum frames that were the screw and glue type. Only a few times on steel frames. Face and chase the BB shell is the first step. It is quite possible the BB shell is not round. If so, there is little one can do outside of thread locker, and even that will eventually loosen.

We never used thread locker, as anti seize was the choice. It provided friction and prevented rust. However your situation may require more extreme measures.

merziac

I respectfully disagree, I can overpower ANY BB with zero damage and 100% success, it has never failed, period.

Road Fan

@merziac, In terms of power to remove a fixed cup, I agree, and I'm curious regarding your toolset. But @63rickert made other excellent comments, like removing everything and starting over with a freshly faced and thread-chased BB shell, new dust sleeve, and a good magnifying glass inspection of the bearing faces. @canklecat agreed with my comments about preserving his original Q and chainline, and that is NOT GUARANTEED without the original parts, or replacement parts that are carefully matched using the techniques of the Sutherland and Barnett handbooks.

Even for a cartridge replacement it's important to chase and face at least the drive side, since the main stability of the cartridge BB is the drive-side cup. So that side needs to be aligned correctly perpendicular to the BB axis, and the threads need to be clean for reasonably accurate torque setting and good thread contacting.

I think I can get adequate installation torque on a cartridge BB and I can remove a BB and most fixed cups. On my 1952 Rudge I benefitted from the Mark Stonich fixed cup tool. But I can't mechanically chase the threads (I can toothbrush them ... ) and I can't cut the faces with my tools. And the price for a quality set is what I'd like to spend on my next flexy vintage frame, workbench and vise, or to refurbish my Woodrup frame. LBSs' where I am will charge at most $100 to prep a BB and install the hard part. Another one of the good ones closed, however.

Road Fan

There are a wide range of hooked tools out there and some stay on the ring better than others. I rather like the technique of using a punch to direct force on the notch, and hammers of differing size to create motion of the ring. I have direct control of the engagement with the ring, but setting the ring while holding the adjustable cup becomes more of a challenge. Some of the newer BB designs are improvements on this score.
@JohnDThompson I like that tool! I have one of those slip-pliers, too! It can be locked with a toe-strap around the handles, too!

canklecat

@merziac: Any tips and tools that ease servicing of older BBs can only be a good thing. I'm definitely interested in your ideas for this chore. I'll PM my email contact info later.

As good as the Hozan "Rock Ring" wrench is (I still crack up over the apparently true story of how that name occurred), a friend who's also a mechanic for the city bike fleet managed to break one. That surprised me because the Hozan is much sturdier than the typical cheap stamped metal wrenches I'd seen elsewhere. In fact, I had to talk my LBS out of one of their spares so I could have it that day. I paid a few bucks more than it would have cost online but I like my LBS folks and they've done lots of little freebies for me.

I'm wondering whether that dual-hook locking plier version in JohnDThompson's photo could compress or distort a lock ring. I suppose it just takes a little extra care to avoid squishing it out of round.

The real PITA is the drive side. That's one of the main reasons I'm considering trying an updated BB like the UN55, which turned out to be much less expensive than I'd expected. I figured it would cost about $50 but it's only around $15. So I'll probably give it a try just out of curiosity.

And I'll disassemble the original BB and measure the spindle to be sure the replacement suits my crank and chainline. I know the local REI has a UN55 in stock but I have no idea what size it is, and they rarely have an experienced mechanic on hand to discuss this stuff.

Thanks again, all, very helpful stuff.

Road Fan

One last thing: before you take down the original BB, measure (as well as is reasonable) the length of the stub spindle on the drive side or the non-drive side. To see if you can maintain your Q and chainline, you need the same spindle length AND the same right-side spindle length. The right-side is defined from the right edge of the BB shell to the end of the spindle. This controls chainline, and it's called side-end-right (SER, there is also a similar SEL). You can calculate it, because:

Spindle_length = SER + BB_shell_width + SEL.

And notice that BB shell, spindle length and SEL are easy to measure, before you pull off the chainring side.

So do whatever measurements you can, but if you measure the SER on the new UN55, you'll be able to predict if chainline will be matched and how much mismatch you may have. You can also see if shimming on the drive side will help to match it.

FlMTNdude

I have replaced the original bb on my bikes with a UN55. No regrets. Still have the originals in case I want to put them back on or as a temp if the cartridge type fails. Can definitely spend more for a little better bb such as interloc, but zero complaints. Meanwhile have had to service my non cartridge bearings 3x so far in the life of a $25 bb. I may have to build my next vintage wheel set with cartridge. I am not riding Eroica where I have to be period correct.

63rickert

[QUOTE=Road Fan
LBSs' where I am will charge at most $100 to prep a BB and install the hard part. Another one of the good ones closed, however.[/QUOTE]

I've never been charged anything like $100 for remove and re-install, chase and face. In recent years that service is usually not charged. When I ask to pay something they will most often suggest I buy something. The shops giving me this free service know very well that I am a cheapskate and have not ever rung much at all through their register. They also know that I am going to ride the bike. They know that I send them referrals. They know that I respect their craft.

Twice I've tried to remove a fixed cup using published suggestions with bolts and washers. Didn't work. Once a guy sat me down to demonstrate how it was done. The guy was not a dunce and had a decent mechanical resumé in other domains. Didn't work. If you can make it work with makeshift tools you are good. Congrats. You also have enough mechanical knowledge to know that Campy tool kits are expensive for good reason. Bicycle mechanics should not be done by "overpowering" and the downside of that approach should be obvious. Once the cup is removed there is simply no way to continue with chase and face without proper tools.

When the LBS are gone we will miss them.

merziac

All good points and totally agree for the most part, cleaning, inspection,and I use a 2 prong process for thread restore that has always got me there. I rarely face unless absolutely necessary as I have seen many frames where it has been done with impunity and are now narrow causing chainline and clearance issues when needing to push limits of spacing and chainring selection. The power is key, getting it undone and then properly tight in the end eliminates a lot of nonsense in between that often contributes to problems.

Going iterate here that I have and use Sugino BB tools that I have had for over 40 years, the lockring tool is especially effective as it seems to wrap around in a reverse spring loading way to grip the ring and always gets the job done as long as I keep the pressure lined up correctly. The DS tool is just plain tough and never fails me, again with the proper force applied.

merziac

Overpower was perhaps a poor choice of wording as it was meant to illustrate the challenge we know it can be. For me there is no downside as it has never damaged any cups, tools or frames. It is done in a very controlled manner with no slipping, distorting or problem of any sort, it just works exactly as it is supposed to.

I have been a mechanic/technician all my life, including at least 25 years professionally as a FoMoCo and ASE Senior Master technician, 30+ years drag racing motorcycles and many challenging repairs at the the track, on the road and everywhere in between. Good tools are key, patience and skill also go a long way with necessity being the mother of invention, thinking outside the box to get the job done also can have a huge impact when it combines all of the above to bring a better solution to light as it has done here.

merziac

Sounds good, my process was originally discovered for the DS and has been enhanced to include both sides.

JohnDThompson 

No worries. the lockring is supported by the cup it surrounds, so even an aluminum lockring doesn't get distorted.