£1 per gramme weight-saving? Pah! £7.99 for 286g here.

[KneesUp]

I've read that it costs about £1 per gramme to lose weight off a bike give or take the odd pound, or gramme.

Well, it tuerns out that isn't the case if you start off with an old enough bike. I'm renovating an old Peugeot road bike bit by bit (and riding it in between) The bottom bracket has been a bit rough, so I took it out for a look. It's quite pitted, so I've decided to replace it rather than re-grease it.

I haven't managed to get the fixed cup out yet (I need a big nut and bolt)but I weighed the bits I have managed to remove and they are a whopping 584g without (much) grease.

A replacement cartridge bottom bracket from Shimano is £7.99 and weighs all of 308g

If I carry on at this rate I will only need to spend just north of £300 and the bike will weigh nothing at all!

So the moral is, start with an old bike and you can make it light for next to nothing.

(and on a serious note, I need lower gearing for my level of fitness / amount of hills locally, which means I need a long cage rear mech, which will save me another 200g. Seriously, if I'm not getting home from work before I set off I will be disappointed)

 

[Tyke]

Love your way of thinking I have an old Raleigh Persuit somewhere a few quid should make it lighter than my new bike. It was always faster but that might be something to do with me being 25 years younger then.

 

[KneesUp]

Love your way of thinking I have an old Raleigh Persuit somewhere a few quid should make it lighter than my new bike. It was always faster but that might be something to do with me being 25 years younger then.

The bike I had 20 years ago was definitely faster than this one too - strange that! (although the bike I had 20 years ago was stolen and was genuinely quite nice - 531 frame, indexed downtube shifters - quite the thing then, a 105 rear mech to replace the one I broke by adjusting it incorrectly and flinging into the spokes, and a 600 crankset I bought cheap of a friend - I'm still annoyed at myself for forgetting to lock the garage)

The Stronglight crankset on this bike weighs over 4kg including the pedals (which I can't get off at the moment). Strong it may be. Light it is not. I think I am going to modify my low-gearing plan by keeping the rear as it is and getting a cheap triple crank from Decathlon. The only freewheels I can find that will reasonably fit are six speed and have a bottom gear much lower than the other five (Shimano mega range) and as such will require a long cage mech. The wheel wouldn't need re-dishing because on closer inspection it's a six speed hub (says Shimano SIS on it) with a five speed freewheel on, which would explain why it needs a washer on one side of the quick release pin.

Anyway, the triple will mean less messing about and give a greater choice of ratios without such a big jump as if I used the mega-range freewheel. I very much doubt the pushrod front dérailleur will cope with a triple - even if it has the movement it won't be able to cope with the different cog sizes because it's not a parallelogram one - so I will need a new one of them, but I'm guessing a basic front mech to use with friction shifters isn't too hard to find.