Planned obsolescence in cycling

Wut. Exclusively used GXP on all my bikes for 10+ years and never had a single issue.

How many km/ miles did you get out of 1 bb normally before it sounded like it had sand in the bearings instead of grease?

So what's the difference between this and a GXP BB? It's functionally identical.

Same here, I change more often cables than BBs. It's contamination what kills them, SRAM aren't the worst sealed but Shimano BBs are better at that

External BBs care a lot more about faced ends than other types; no amount of sealing will preserve the bearings if they're a tad cocked.

They are not.
The Sram axle is stepped, which causes the nds bearing to take all the axial load, causing it to wear out quicker than the ds one.

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They are not.

I know the difference between a HT2 and a GXP BB; I was asking why a HT2 BB with an added GXP sleeve and wave washer would last any longer than a GXP BB

You can use a Shimano ht2 BB with a '22 to 24mm' adapter and a wavey washer on the driveside

You'd then effectivelly be using a GXP crank to prematurely fuck an HT2 bb.

Its the stepped axle and shifting of axial loads to a single bearing that causes the issues with GXP and you'd still be doing that with an adapted HT2 bb

The bearings in an HT2 bb might be superior to those in a GXP bb but given that the GXP nds bearing has a smaller ID you'd hope that it ran larger balls to cope with all the axial loads so adapting an HT2 bb actually sounds like a way to make a shit system even worse.

Because of the adapter there is no step anymore, it's basically a straight 24mm spindle. So the axial loads are now shared between the 2 bearings, like with Shimano cranks.
And apparently the bearing quality of Shimano is better too.

given that the GXP nds bearing has a smaller ID you'd hope that it ran larger balls

I've never seen a GXP BB like that; they're the source of the adapter sleeves, aren't they?

Because of the adapter there is no step anymore, it's basically a straight 24mm spindle. So the axial loads are now shared between the 2 bearings, like with Shimano cranks.

This sounds like a GXP BB being used with a HT2 crank.

... Just realised, this is a fair old derail here, lads

This sounds like a GXP BB being used with a HT2 crank.

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Related to earlier in the thread (DMR pedals), in a fit of pique I have bought the following tools if anyone wants to borrow them?

• DMR Original V12 & Vault Tool*
  
• DMR V8 Classic and V8 Mag Servicing Tool
  
  

*also works for V11s too apparently

A Different Take

This is an article I wrote some time ago for the Veteran Club newsletter. I hope its relevance can be seen as the opposite approach to the desire to have the latest bike. I can only hope that it won't be TL;DR.

I'm well aware that this Dragonfly Roadster wasn't ever a very good bike. However, if you're not racing the important question is whether you perceive the bike to be satisfactory.

A Dragonfly

My Mother was the proud owner of this Dragonfly. (see pics. below)

A completely standard rod braked roadster, it was never really a great machine but my Mum was very attached to it, and rejected more modern and apparently superior machines that were offered to her. There are two aspects which I believe are worth recording, but I’ll describe the bike first.

It arrived as a twenty first birthday present in 1934, although I understand it was a 1933 model which my Grandfather acquired for her at the discounted price of 3 guineas (reduced from 4 ) as it was old stock. It has a 22” frame with 26 x 1 3/8th Westwood rims, bolted up seat stays and ‘North Road’ upturned bars with an expander bolt stem. The Williams chainset shown in the photo is a late addition (I reduced her gearing slightly as she approached eighty). The original gearing was 66.4” The head badge was a transfer of a dragonfly, but there is only a tiny fragment remaining.

One small adjustment my grandfather (a former track rider) made for her was to put the handlebars down as far as they would go, which gave her a slightly more efficient riding position than most users of this type of machine. It is not especially heavy – about 30lbs if you removed the remains of the child seat, and this is probably its best feature.

This brings me to the first point of interest. Nowadays we generally think of these roadsters as just utility machines, only suitable for shopping or commuting, but originally they were also used for recreational riding. My Mother certainly used hers as a touring mount – I don’t know how much she did, although cycling was not her main sporting interest. However, there is a story I think will bear repeating.

One summer in the late 1930s she went on a youth hostel trip with a friend which took them from London into Wales, and what was intended to be their penultimate night was spent at the newly opened Wilderhope hostel. They got a good start in the morning which was necessary since their next intended stop was Oxford, about 100 miles, quite an ambitious target for anyone carrying luggage and using a single gear. Luck was on their side and they had a good tail wind which got them to their destination by mid evening, only to find the hostel full. This was a blow since money was clearly not plentiful – there was some discussion and in the end they decided that with the wind still favourable and some moonlight, they would push on home to Teddington (Middx.), about another 55miles including the ascent of the steep side of the Chiltern ridge to Stokenchurch. They arrived, still in good spirits, at 2 am.

Perhaps it was the memory of this ride that made her so keen to stick to her Dragonfly, or possibly sheer bloody mindedness, but I believe the second point of interest is that many people of my Mother’s generation expected things to last, literally, a lifetime. They did not feel the pull of retail therapy: they had acquired the tools for life which they felt were necessary and they were jolly well going to keep to what they had. For example, at some point about 1980 my Mum complained to me that her bike didn’t feel quite right, and that the chain had become much too tight.
It didn’t take long to diagnose two broken chainstays – the chain was all that was holding the bike up! I told her the machine was knackered, but she insisted she wanted it mended. Some third world style patches were brazed onto those chainstays without even doing much dismantling, and as you can see in the photograph they are still holding the bike up. Faced as we are with the problems of debt and global warming perhaps there is a lesson here.

The Dragonfly now hangs in my garage and is unlikely to get much more use. Everything about it is worn out, excepting that C34 chainset I fitted near the end. All the same I do have a small hope at the back of my mind that some day, probably after I’ve gone, some one will see fit to restore it.

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What bars?

On a more serious note, I enjoyed the article, thanks. It would be nice to see it all fixed up.

Needs leaving as it is - it's only original once, as they say. Spend the time on recording it's history/provenance

Great tale, thank you