55murray

My 1980 Miyata 610 cranks get a little play in them every few turns. The whole BB was loose a few months back and I could not get the cranks off so I had my LBS do the work. They said it looked fine and they just cleaned and relubed, I forgot to ask but I doubt they replaced the bearings even. Is this something I need to worry about, sure seems a little odd to me.

rgvg

Sealed or cup and cone? I had a bike with the bottom bracket coming loose and I was soooo sure the adjustable cup was tight. Turns out the fixed side was loose. Doh.

merziac

So arms loose on the spindle, spindle in the cups or cups in the frame?

Set up and adjusted correctly, none of this should come loose at all.

I would not ride this until it is completely sorted out, cause, effect and remedy.

No way this would ever end up at the shop, exactly for this reason.

This is why we have cartridge BB's now, hate to think of the good cup and cone parts that have been lost this way.

philbob57

I recommend attending to it pretty quickly. I couldn't have ridden even 100 miles with a BB that got a little loose. I took it into an LBS I was close to when I realized what was happening, and a mechanic adjusted it correctly while I waited, but my axle got trashed, and I'm pretty sure that was because I had ridden with a loose BB. Maybe the Japanese stuff on your Miyata is more durable than the TA axle I had, but why take a chance?

55murray

Thanks, so clarifications are original cup and cone, and spindle starts to play in the cups. Just rode it 66 miles last night...

merziac

Well that still means one or both of the cups are coming loose so it all needs to come apart and be evaluated, sounds like one of the cups isn't staying tight.

I would get it apart, clean all the threads and have a good hard look at the cups and BB shell then get after it with this setup to make sure the fixed cup is tight.

This same setup will always get them off when they are stuck without damaging any parts, pieces, tools, frames or flesh, ever, period.

juvela

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one thing which might cause this symptom is damaged threads

simple enough to disassemble everything and check them

if damaged, chasing might be adequate to sort things

if damaged and chasing not adequate you could tap the shell out to italian

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one odd thing which can cause an adjustable cup to loosen is if bottom bracket threads to do not go far enough in toward the centre of the shell

had one case of this in me workshop where the adjustable cup was butting up against the end of the threads right at the point where the bearing adjustment was correct. this caused end loading on the cup which caused it to loosen - an odd problem indeed.

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SurferRosa

Might be as easy as replacing the lock ring ... if it's the adjustable cup that is moving on you. Blue Loctite might be of some help.

Sorta a pita, but you can usually tighten the lock ring without removing the nds arm

rustystrings61 

Are the bearings caged? I had similar problems with a Sugino BB when I put the caged bearings in facing the wrong way ...

55murray

Thanks much for all the info everyone! I'm taking your advise and putting the bike in inactive status until I take it apart and look at everything you pointed me to. I'll let you know what I find!

dddd

I've seen quite a few cup/cone bottom brackets where poor tolerances together with perhaps a less-than-perfect bb shell conspired to cause such symptoms.

So it may be no fault of the shop who rebuilt yours. I might just tighten the adjustment myself if that can get rid of the play without causing binding.

And as was mentioned, sometimes a bearing retainer gets put in backwards, or one or more balls falls out of place during assembly. Sometimes a ball breaks in half and causes problems, so I would inspect those closely and perhaps replace them with grade25 pieces.

Bianchi84

I'm wondering if incorrect number of / wrong size / mismatched loose bearings could be the issue. It might seem tight at first, but as things start moving it goes out of adjustment.

cbrstar

When you have a BB that old you have to take it apart and clean the old grease out completely because grease crystalizes over time . I've seen so many bike shops squirt a little bit of new grease in there without proper cleaning. And it works for a little while then gums up and things start to loosen. But with the amount of riding you have done with it loose there's a good chance it's shot now. Luckily BB's are not that expensive to replace and I'd just buy a new one.

55murray

Where would be a good place to get new parts, or good old parts? One thing I have not mentioned, is that when it came back from the shop I had to adjust both limit screws to get the shifting to work well again- it seemed that the rings moved closer enough to the frame to require this (it would jump off the large ring and would not reliably drop to my granny).

Yea, I have probably ridden the bike too much with this issue. It is my only decent road bike.

clubman 

Suffice to say that you can't trust at least one mechanic in that shop. I'd mention it to the boss just to see what he says. A standup guy would appreciate the feedback.

repechage

Oh dear-
upon taking it apart, note if the spindle has a longer side of favored projection, longer is for the drive side. (asymmetrical)
A big enough change in position upon service suggests to me-
flipped spindle
(other organic problems as noted earlier)
lubricated tapers /arms - I suggest dry fit, not lacquer thinner dry, but not greased.
there are many young mechanics that just don't have the "knowledge"

What brand / model of cranks are you working with?

merziac

When I jumped back into bikes about 10 years ago, I went around to most of the shops to gauge their C+V acumen, it was abysmal for the most part. The funny thing is, my local Performance was the most onboard from the manager on down.

The rest were always like "huh, what, oh so and so is the old bike guy" some of them were none to thrilled about it and some pointed me to a guy that was all of maybe 30 and far from enthusiastic so most were not a place I would recommend.

At this juncture we are too far down the line with threadless, cartridge, throwaway cookie cutter, profit at all costs crap to trust anybody else with our stuff, if we want it done right, we need to do it ourselves.

Most of this is not that hard, until it is and when a shop gets stuck, they are often quick to "upsell" you to the modern corner cutting cartridge or whatever "the old one was worn out, just old, too fussy, etc." , in other words they couldn't figure it out, may have screwed it up so here you are, not original anymore, old parts scrapped, SOL.

55murray

Thanks for that tip, I'll look out for that! It is a Suntour Custom Triple.

clubman 

Customs come in double and triple flavours...I have a triple mounted on a bike.

John E

Interesting -- I have never had an English or Swiss (left-threaded) fixed cup come loose, because they self-tighten as you ride. In contrast, I have had to resort to Loctite and heavy torque to keep some French and Italian fixed cups fixed, because they self-loosen as you ride.

55murray

That is dead ringer for what I have!

cbrstar

There's quite a few shops down the road in Indianapolis. I would try googling "BIke Co-Op" which I think there was 4 listed!. It would be the cheapest route and you will get a chance to learn how to fix it yourself.

clubman 

If I find time tomorrow, perhaps I can pop the crank off for a measurement.

Charles Wahl

I will second that emotion: count the bearing balls on each side, and measure their size -- when I first read this thread, that's the thought that occurred to me, but it's such a stupid error that I was embarrassed to bring it up. However, if bike shop maintenance was involved, there's no end of reasons why you may have gotten the know-nothing, who failed counting and "some of these balls are not like the others" in grade school, wrenching while doing a Lothario on his phone.

55murray

Well, everybody was pretty much spot on about this! Components pretty much trashed, the worst being the fixed side cup. That cup was not completely loose, but it was not as tight as it should have been it came loose with very little effort. Sure enough, the spindle had been reversed by the LBS, with the short side on the rings. It had caged 9 count bearings, properly installed, with some just falling out of the cages upon disassembly. Good news it the cranks are OK, the BB shell is good with all threads in fine shape.

Debating about trying to stay vintage or just get a cartridge, standard English size and threads, seems to be 124.5mm spindle. I don't think I need to worry about the offset on the spindle since the bike seemed to run just fine with the thing reversed!