Stronglight Bottom Bracket Misery

I've had a pretty good week parts-wise - my 1980s single bolt Dura Ace stem arrived - which looks so good I did a bit of a sex-wee after I put the bar tape on. I finally got hold of some chainring bolts that fitted and didn't come loose after a few days because they were slightly too long, and I was looking forward to finally getting my chainline sorted out by buying a new bottom bracket to replace the road double one (too long) that I'd been using up until now.

It came in the posts today - Stronglight 68 shell with a 107 spindle. I excitedly smeared it in anti-seize and started screwing it into the frame - and then it stopped.

On my Mercian, there's a steel band in between the bottom bracket threads which, while I thought was a nice bit of attention to detail when I got the frame, is proving a pain in the arse now. Basically, while my previous Shimano BB had tapered ends to the threaded part, the Stronglight one is the same thickness all the way - so the threaded section is essentially too long to fit snugly - I have around 5mm left sticking out when it's screwed in as far as it can go.

The question is, can I do anything? I'm looking at it two ways:

1) Could someone let me know if there's any way of reducing the size of the thread? I notice there's an unthreaded section about 5mm long which, if removed, would probably be enough for the BB to fit, but don't know how or whether to do this.

2) Can anyone let me know whether there are any bottom brackets out there (no need to be track specific) with a shorter (or tapered) threaded section that's likely to fit this Mercian - and if so, where I can get one from? Not looking to spend a lot - the Stronglight was a tenner, so you can see where I'm coming from on this!

If 2) turns out to be the easier option, anyone want to buy a Stronglight 68x107mm BB? Cost £10 and is brand new...

Thanks!

try a shimano BB?

try a shimano BB?
yep, a big £10 if that at wiggle or just screw the fucker in and pray to the gods!

try a shimano BB?

Thinking about it, but I've noticed that the BB cup is narrower on the Stronglight than on the Shimano. While it doesn't cause problems with the double spindle, I'm wondering if with a shorter spindle it might cause the cranks to rub or grind against the cups. I'm not using track cranks - just a pair of Campag Chorus on a single chainring.

And the Shimano ones come with plastic non-drive side cups, which isn't that important, but nice to have metal ones...

Hopefully photos show what I'm talking about - first one shows the band in between the threads - it ain't budging for nothing, and the second one shows the difference in the cup protruding from the shell.

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that collar in the BB is weird...

I've had tubes protruding into the lugged BB shell before, and had to put the bb taps through to clear them back a bit, but that thing looks to much to try and tap.

it's common in old frames designed before cartridge bbs came into play.

Still having problems, but thanks to discussions in other threads I think I know where I'm going...

I'm going to measure the how wide the threaded area in the bottom bracket shell is later, but was wondering if there are any ISO BBs out there that have a particularly narrow threaded section?

If you have a look at my pics above - esepcially the one of the Stronglight BB next to the Shimano, you'll see that the Shimano threads are shorter, and so fit the BB shell. The Stronglight is too long, and so hits the 'step' in the BB shell. I don't mind buying a loose cup BB, as I might be able to hacksaw off the extra length. I notice the Miche Primato doesn't have flanges, so would assume I don't have to screw it in all the way, but will that affect how I tighten the cranks?

that must be quite an old frame.
i assume the metal sleeve inside was there because there's an oil port on the BB Shell (that little nib on top next to the downtube), it's to prevent oil from getting into the other tubes (seatstays etc.)

i personally think u're not going to get the stronglight BB in... but remember stronglight BB's are JIS taper and miche are ISO if u're going to swap. chainline difference there.

i personally think u're not going to get the stronglight BB in... but remember stronglight BB's are JIS taper and miche are ISO if u're going to swap. chainline difference there.

Sorry Ed - old thread - we've already established that the Stronglight BB won't fit, so that's just languishing in a tool box until I can be bothered to list it on eBay (or give it away on here...).

The frame is indeed an old one - 1955 to be precise - although it has the modern decals on, so I'll be taking it up to Mercian when I pick up my Holdsworth for them to verify that it is actually a Mercian. I've got no reason to believe it isn't though - fantastic quality and geometry and the Nervex 48 lugs date it around that period too.

At the moment the cost of a BB is working out at less than the cost of a new set of cranks (although with the number I've bought that won't be the case soon), so what I'm looking to do now is find a BB that's ISO tapered that will fit in the BB shell without hitting that collar...

try a shimano BB?

or try to pick up something NOS at a jumble or from Tour De Ville bikes or Roberto

or take the frame down to your LBS (of course i don't mean evans or cyclesurgery or that sort) and see if they have anything that'll fit. sure they'll have a variety of BB's lying around they can try screw on.

Still here I'm afraid...

I should have a Miche Primato BB waiting on the doormat when I get home, and having had a bit of a search, it looks like my BB tool ain't gonna fit. Looking at the BB tools out there, they bear more than a passing resemblance to a cassette lockring remover. Would my Shimano cassette remover do the job, or is there that much of a difference between the Campag one (which apparently fits) and the Shimano?

While I'm at it, as I have a small stack of BBs, can anyone confirm that I can (safely) use the 107 spindle Shimano BB with a pair of Campag Chorus cranks on my geared. If the difference in chainline is around 4.5mm, then it stands to reason that this would create near enough the correct chainline for a road double? Or should I just buy a Campag BB?

Still here I'm afraid...

I should have a Miche Primato BB waiting on the doormat when I get home, and having had a bit of a search, it looks like my BB tool ain't gonna fit. Looking at the BB tools out there, they bear more than a passing resemblance to a cassette lockring remover. Would my Shimano cassette remover do the job, or is there that much of a difference between the Campag one (which apparently fits) and the Shimano?

shimano one won't fit.And it's not just any campag one, you need the record BB tool.

shimano one won't fit.And it's not just any campag one, you need the record BB tool.

Right you are - managed to get it in with various bodges, but will be getting the proper tool from Outspoken to do some fine tuning. The adjustable chainline thing is brilliant - I'm in full on stealthy silent running mode now. Shame the cartridge itself is just a generic Slovakian job, but then at that price it's no biggy. Amazed at the difference there is between the ISO and the JIS.