Brompton owners

When in perfect condition.....

One day I'll get myself a Brompton front wheel built with a Phil Wood hub.

For now, I'll use my relatively new Brompton hub until the rim wears out, which should not take too long with the gradients in Sheffield. A bit more Web searching suggests an optimal set of loose ball bearings will be Grade 10 Chrome, which have a hardness of 60-67 HRC, compared to the Grade 100 Stainless ball bearings with a hardness of 52-55 HRC. Simply Bearings seem to offer them relatively cheaply.

Campag, I've been led to believe, only use grade 100. Wouldn't softer balls balls save cup and cone wear.

The grade of bearing refers to the shape of the ball, rather than its hardness (which is measured by the HRC value) , with larger grade numbers indicating greater departure from a perfect sphere:
https://en.wikipedia.org/wiki/Ball_(bearing)

The ball bearing entry in the late Sheldon Brown's cycle maintenance Web archive at Harris Cyclery suggests that Shimano Dura Ace and Campagnolo Record use grade 25 ball bearings:
https://www.sheldonbrown.com/harris/bearings.html

In reply to the question raised by @ElephantBreath on harder vs softer materials --- Park Tools' Web site discusses the issue of ball bearings in the context of ceramic ball bearings being harder (HRC 75) than the bearing surfaces of the cup and cone system (HRC 55-60). They suggest that higher hardness values for the ball bearings "should provide good wear features for the entire bearing system, not simply the ball bearing itself. ":
https://www.parktool.com/blog/repair-help/ceramic-bearings

So from what I can see, the grade 10 chrome steel bearings with hardness of 60-67 HRC offered by Simply Bearings should well exceed the requirements of all qualities of cup and cone bicycle bearings, for what seems a reasonable cost.

Friends bikes up for sale... built it for him in November.

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what's replacing a rear triangle going to cost? Managed to snaggle a titanium one, so am going to swap it for original.

£22.50 parts of your hinge is worn, £12 if not. SJS charge £20 labour. Have seen up to £80 labour for this job...

Nice build.

Would have preferred an Alfine or some kind of gears!

He’s a moron... easy upgrade though!

Ps. Selling our two demo Rohloff bikes ... so I can build two more! Purple metallic and gloss black lacquer frame await!

How much for the one with disc?

£3045

Good price. I'm pricing one up with full Alfine through a trade acc and yeah, your price is pretty good for a build with Alfine!

thats £3045 with Deore M6000 and Rohloff!

I know that and I have my own build in mind. Gonna go Alfine Di2, dynamo disc front and build it up myself after flogging off bits from a 2020 S6L.

Smart. sounds fun!

We'll see, 9 weeks wait for the Brompton. Will strip it down and flog off the bits and see how far I can go with the funds raised from the bits.

Still thinking if I should keep the bits and update my M6R-X...

Blimey. I can’t be waiting to order bikes from Brompton, takes far too long!

I can't just take one out of stock, besides, I want one of the newly released colour!

Why not?

Either wrong bars, speed or colour...

I finally got to try out a Brompton and am now ready to take the plunge and buy one (when my Cyclescheme Application comes through)

Just wondered what people thought of the Alfine Conversions as I did not quite like the gear changing on 6 speed I was testing; albeit maybe it was just because it was heavily used and quite old? It just seemed quite hard to change gears when going uphill. I thought the brakes were pretty good so probably no need for me to go discs.

I’ve got a Alfine (courtesy of SJS), and changed from a 6speed. I found the Sturmey hub a lot smoother and freer running but for any hub gear you can’t change whilst putting significant pressure on the pedals. You need to back off then change gear, same as you would with a derailleur.

I change over as I wanted disk brakes so thought why not, but if you don’t need disk brakes then I’d have stayed with my 6 speed.

Ah thanks for the info, I guess I am just too used to riding my road bike. I guess I could use the money I thought about putting towards a conversion to lighter aftermarket parts!

Photo?

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