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resolvedAccording to Strava my 6-speed Brompton has done 550 miles from new. I use it (occasionally, as you can see) in all weathers and all year round. It currently has the factory-fitted chain on it.
According to my chain wear indicator, the chain is now over 1% stretched so must be replaced.
The Brompton manual says change the chain and sprockets every 2,000 miles or so. 558 << 2000.
If you're a Brompton owner, do you only get 500 miles from your chain?
In the winter yes, 500 miles wearing out a chain is not unknown. You might also need to replace the sprockets.
Weefolding is right about the non-longevity.
I think I squeezed out 800 miles from my 6 speed Brompton's original chain and sprockets. The rear rim lasted about 500 miles from those Fibrax brillo pads.
I replaced the chain with a Sram PC870 and 1500 miles later it's at 0.75% elongation. Sprockets were like-for-like replacement from Biketrax. For what it's worth, I use Green Oil and clean it every so often.
Do Bromptons do something in particular that speeds up chain and sprocket erosion? Asking for a friend.
Three things.
The chain runs closer to the ground, it runs faster and it wraps round a smaller sprocket.
Unlike a 'normal' hub geared bike Bromptons have an added chain tensioner for folding, so the chain doesn't just run round 'in a circle'.
Many old three speeds run 'for ever' even when the chain (and everything else) is very worn just by pulling the wheel back to maintain enough tension for it not to fall off.
6 speed Bromptons also have a derailleur which adds to chain wear (even though it's only 2-speed!)
Being a small wheeler the chain is a bit closer to the ground and more likely to pick up muck.
Plus what WFB said!
Thanks Arellcat and WFB. Looks like the answer to my original question is "Yes", then.
Have ordered new chain and sprockets, and look forward to taking off the back wheel for the first time. When the manufacturer of the bike says 'watch our video to show you how to remove the wheel' you know you're in for a fun evening.
I've also ordered some different brake blocks (Swissstop green) which I'm told work better and erode the rim less than the Fibrax ones. I was kind of aware that the grey gunk over the back of the bike is actually bits of my rims, but hadn't put two and two together in terms of the rim wearing out in 500 miles.
I used to fear removing the B's rear wheel too. On one morning commute it led to me walking 2km back home with a flat tyre. Having a spare tube would've helped, but only if I'd been able to remove the wheel!
1) Deflate tyre
2) Unscrew hub gear toggle chain from its adjuster
3) Optionally unscrew the chain from the axle
4) Unscrew window nut from axle
5) Remove chain tensioner (easier upside down with wheel 'parked')
6) Loosen axle nuts and remove wheel
Putting it back on is the reverse of removal, except that you mustn't screw the window nut back on much more than finger tight - all it does is hold the tensioner in place, and too tight will distort it. You adjust the toggle chain with the hub in 2nd gear, and the rod's end should line up with the end of the axle.
Have any Brompton owners ever tried the keep-a-spare-tube-wrapped-in-place-trick? Sounds almost more trouble than it's worth.
It's really not that hard to deal with the back wheel and the bike stays standing up for you with either wheel removed.
And no cb, that seems like more bother than just sticking with old school wheel fitting.
Bear in mind it's often possible to do a working repair on a tube without removing the wheel, if it's fairly obvious where the puncture was.
1 - locate puncture and deflate any remaining air as required
2 - remove tyre on 1 side
3 - pull out enough tube to effect a patch repair
4 - ensure inside of tyre is clear from whatever punctured it
5 - seat tube back in place
6 - seat tyre back in place, being careful not to pinch the tube
7 - inflate and hope nothing is pinched and you did a good patch job
Sometimes less hassle than removing a wheel on a fixed / hub geared / drum braked-type bike, if it's dry and you can see what you're doing.
@kaputnik. Indeed. I've only had one puncture on the Brompton and it was on the rear wheel. I didn't walk the bike home like Arellcat, instead I bagged it up and put it on the bus. At home I stood it on the kitchen table and did as you describe.
I don't bother carrying any tools on the Brompton because I only ride it round the town. I reckon that if I have a failure I will just jump in a bus or taxi and sort out the problem later.
My friend's ardour for the idea of a Brompton is cooling somewhat. Mean time to failure seems much too short.
@Instography. I don't count punctures as failures. They happen to any bike. I am a bit disappointed with the rate it seems to be eating 'consumables' like chains, but it is a specialised design and is optimised for what it does in the same way that a carbon road bike is. Those too aren't exactly cheap to run.
I was at a meeting in town this evening. Several people came by bike. I went by Brompton, folded it and took it into the room. The rest locked their bikes outside. At the end of the meeting I just unfolded mine and was ready to go while the others were all still messing about with locks and chains and stuff. It folds and unfolds in seconds.
There are compromises to make it pack so small, but the positives are that it makes multi-modal transport so easy and it's an outstanding piece of engineering, perfectly fit for its purpose.
Och, I know. My friend is very likely to find that the idea of a new bike on the C2W is irresistible.
Well I spent a happy evening yesterday taking the back wheel off and replacing the sprockets and chain. Like Arellcat said, it was actually quite simple (certainly no worse than the Alfine hub on my other bike). What made it particularly pleasant was that I had the bike 'parked' on the kitchen table, and did it all while sitting down. The only tricky bit was replacing the springy split ring that holds the sprockets on.
When doing the replacement I realised the cause of the short life of the components. Last year I went on an 'Essential Cycling Skills' course, which involved lots of riding round on a sandy all-weather pitch. Last night I found a lot of sand still stuck to all the bits round the rear hub. How embarrassing. I need to wash those bits of the bike more often, I reckon.
Next thing is to test ride it to make sure it's working...
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