Archive for the ‘bottom brackets’ Category

the green frame

the green frame

This frame is the next project, and one that came re-built as a single speed but I’ve decided to fully overhaul it and make a few changes. I think it dates somewhere between 1958-60.

a spot of colour under a clamp

a spot of colour under a clamp

It was originally a beautiful emerald green over gold and has faded to a more sedate shade that still looks rather elegant. The paint and decals are arguably in the best condition of any of my Special Sports frames. That doesn’t mean it looks like new, however !

the head lugs differ

the head lugs differ, original loose ball headset

One difference from the other Special Sports frames in my collection is with the head tube lugs, which are similar to those on my Flash in being a bit more ornate at the top and down tubes. The other lugs are standard for the Special Sports.

serial number

serial number

I’ve had a few dramas removing the fixed bottom bracket cup from both the Flash and this bike. If you are having problems with an English ‘BSA type’ fixed cup that has no flats on it, e.g. T.D.C or Brampton, have a try at this method :

shift ... you so and so !

shift … you so and so !

You’ll need a fairly short M16 bolt and nut and some appropriate spacing washers. Five bucks or so from Bunnings ( unless you need lots of washers – I had some already ). Just make sure to use loosely fitting inner washers inside the cup, or the bolt or washers may not come back out. I’ve used a socket spanner to hold the bolt and a large shifter ( a ring spanner is better ) to tighten the nut clockwise – which also happens to be the unscrew direction of the drive side cup.

out, out !!

out, out !!

Voila !

It let go – probably had been there for 50 years. Don’t forget to put anti-seize compound on the new one !!!

the inside washers help the socket grip the bolt head fully without fouling on the cup sides

the inside washers help in engaging the bolt head fully without the large socket fouling on the cup sides.

I’m also making it a habit to re-tap the BB threads on the tight ones. The new fixed cup ( or cartridge ) should thread in most of the way by hand if the BB threads are good. Unfortunately the tap and face kits to do this aren’t cheap, but the Lifeline one ( from Wiggle ) is reasonably priced and works well.

I have quite a bit more to do on this one … it’s time for a ride !

the reborn flash

the reborn flash

See Ya !

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I guess I’m something of a slave to the square taper bottom bracket – they’re almost ubiquitous on the bikes I work with apart from the dreaded pre 1980s (or so) cottered ones. I know there’s stuff that is lighter, faster, more aero ( etc., etc. ), but it all seems to get outdated so quickly nowadays … ( read splined ‘Octalink’, and we won’t mention that ‘Isis’ one here …  hmmm, nasty name .. ). We’re now into ‘hollowtechs’, ‘mega-exos’ and various pressfits, but none of the hard rubbish bikes I find seem to have these fitted  — funny, that.

You can even recycle used tapered ones sometimes, if they’ve been reasonably cared for, though the attrition rate is very high on your typically neglected ‘chuck-out’ bikes. Of course usability depends on the chain line of your intended build, so it helps to have a variety to choose from.

The re-cyclist’s motto – “If in doubt, chuck it out” — I mean, even a freebie re-cyclist must have standards you know … and there’s not much that’s worse than pedalling away on a grinding, grumbling BB.

Here then is a sample of my rejected parts from a recent cull of dismantle-a-thon BB components :

scrap !

scrap !

( The 3rd law of re-cycling states that for every dismantle-a-thon there is an equal and opposite need for a de-grease, clean and sort-out-fest …. ).

And some of the saves :

with no ball bearings

various square tapers, with no ball bearings

and some useful bits ...

and some useful bits …

These days it’s more common to buy a sealed cartridge, the advantage of which, of course, is no maintenance, but if anything does go wrong there’s little one can do. While I generally don’t have a problem with the old style BBs they can be vulnerable to grit and water ingress, and not just the cheap ones either. Sometimes the bearings can be good on one side and shot on the other. It seems the drive side fixed cups suffer the worst, in my humble experience. Murphy’s law …

Usually the ball bearings and axle races are first to go, suffering tiny pits on the rolling surfaces, and gradually the pits grow larger and deeper until the harder cups are also affected. I find that loose ball arrangements generally last better than caged ball bearings and are much, much easier to clean and degrease too. I may be the only person alive that sometimes recycles those cages – with a toothbrush and kero yet !
It’s probably a good idea to replace the balls when servicing, but if everything is shiny bright and smooth I reckon it should be OK to simply clean and regrease.

i like these rubber seals ...

i like these rubber seals …

Although the inner plastic sleeved bearings should last longest, the contaminants can get in via the outer gap between axle and cup. Some cups, typically the better ones e.g. some Shimano came with rubber seals at this point ( above ) and all the cartridges seem to have these as well, for longevity – a necessity when they can’t be serviced.

some cartridges

some cartridges

Removing the dreaded neglected BB can be a total nightmare, even with the recyclist’s essential tools.

If you’ve ever had a truly stubborn one you’ll know that the moral of the story is to either grease all surfaces on re-assembly ( for steel to steel ), or preferably use copper anti-seize ( on steel to alloy interfaces ). You’ll thank yourself profusely ( or the new owner will ) when overhaul time comes !

My Essential BB Removers :

1) The Cyclus fixed cup remover – if you can find one ( or a large flat spanner if you can’t – good luck with this ! ). The problem with spanners is – they slip !

the magic cyclus fixed cup remover !!!

lower — the magic cyclus fixed cup remover !!! and a poor backup, top.

the tool's flats match the cup flats and the hex clamp holds it in place

the tool’s flats match the cup flats and the hex clamp then screws in to hold it all in place

2) The handy C-spanner for lock rings :

lhs adjustable cup and lockring tools

2) & 3) —left hand side adjustable cup and lockring tools …. and a rather heavy handed hammer !!

3) The Adjustable 2-pin spanner for adjustable L.H. cups ( above ).

splined tools - these are for cartridges

splined tools – these are for cartridges

4) For Cartridges – either the freewheel spline tool ( e.g. for Miche brand ) or the ‘Shimano’ spline tool – preferably one that can be bolted onto the axle for safety.

There are a few fixed cups around that don’t have flats on them, which means the Cyclus won’t work … curses.

You’re on your own here, generally with a pin spanner ( or the hammer & punch ) – so good luck !

a couple of fixed cups - the left is more common

a couple of fixed cups – the left is more common

these tools are good for adjusting but not so for removal

these tools are good for adjusting but not so great for removal – refer to hammer and punch !

Applying a penetrating or releasing agent around the cups beforehand may help, but it’s often unable to reach the worst affected threads because of the cup’s depth and tightness.

Of course there are also a couple of related issues to getting the BB out, and they are – removing the pedals (optional), and removing the cranks ( semi ).

On a really stubborn cotter pin or square taper axle it is sometimes possible to remove the axle together with the crank and pedal as a last resort IF you can get the drive side crank and chain wheel off. This is done by loosening the lock ring, then using a hammer and thin nail punch sideways on the pin holes of the adjustable cup to turn it slowly anti-clockwise and off, along with the axle and L.H. bearing still stuck together. This works well if you aren’t planning to keep the bottom end anyway.

Doesn’t do much for your prized punches though, or indeed the cup and lock ring, but, if it works ….

Often it’s the non drive side that is really stuck, so this can be a useful thing to know.

cottered crank set from the oxford international

cottered crank set removed from the oxford international -using the above technique

Recently, I had to remove a seized cartridge BB from an Apollo Kosciusko MTB. As a last resort I used a socket spanner on the spline tool with a long length of 2″ pipe as a lever. I don’t exactly recommend this, but it worked !

I won’t mention that the air was kind of purple coloured with profanities, and probably the previous owner’s ears were burning as well, during this procedure …

And you thought i was a sensitive new age recyclist, dear reader …

the heavy handed approach ...

the heavy handed approach … grrrr !

no wonder !!!

rust … no wonder !!!   (N.B. washers de-centred after i loosened the bolt )

if you’re going to use this subtle technique, the tool must be fixed to the axle as shown with large washers or similar, using the axle end bolts, for safety. ( Those of you with eagle eyes may notice that the above shot shows the cartridge mistakenly posing on the incorrect side – lol )

Of course it always helps to remember that the drive side fixed cartridge or cup loosens clockwise … that can be tricky to figure out if the bike’s upside down — Uh-oh !

spotted while riding

spotted while out riding

Happy Re-cycling …

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