Supercommuter?

[belgiangoth]

Are hub brakes really adequate for commuting? (not rhetorical question, I had just been led to believe that they don't have the stopping power on large wheeled bikes).
I'd skip the rear derailleur and go fixed.

[Brucey]

Are hub brakes really adequate for commuting? .

yes, I that has been my experience. See my post of yesterday at 7.34pm.

cheers

[belgiangoth]

Just worked my way back there, not sure how I missed it. I like the idea of front hub breaks (though it rules out my SON dynohub), will you not need a very strong fork to deal with the moment necessary to brake with a hub gear (similar to disk brakes) compared with the greater distance (smaller moment) for rim brakes?

[Brucey]

yes, but the reaction arm extends almost half-way up the fork blade, about twice as far as a typical disc mount. Also I don't think the peak force with a 70mm drum is quite as high as with a disc brake, even if the averages are comparable in a hard stop.

I have heard of people bending curved fork tips out straight with disc brakes, but not drums. I guess you would think twice before fitting drums to the very lightest forks, but it seems not to be a problem for most forks out there.

cheers

[belgiangoth]

tempting. I'd want a dynamo with that though.

[Brucey]

tempting. I'd want a dynamo with that though.

you can have one, too, but it will either be a bottle generator, or a hub generator that (according to test data I have seen) is not very efficient when it is off-load.

SA do an X-FDD (70mm brake + hub generator) or an XL-FDD (90 mm brake plus hub generator).

The generator is available with a 3W output, or (for the Clogsters) a 2.4W output. I don't know about the 2.4W one, but IIRC the 3W one drags almost as much with the lights off as it does with them on. This is OK if you always ride in the dark, I suppose (the efficiency isn't that bad with the lghts on vs a lot of other generators BTW), or you don't worry about a few W of extra drag. I guess the extra drag might be the same as having a slightly low tyre pressure, or having a strong/heavy tyre vs a lighter, more supple one.

cheers

[belgiangoth]

The extra drag will help with stopping in a hurry!

[LuckyLuke]

Hi Brucey, compliments on a job well done. I didn't know of many of your special mods, interesting stuff. (Your code name isn't "Q" is it? )

I've been daydreaming of my perfect winter commuting bike for a while. I'd want:
-Hub brakes.
-Full length steel guards and front mudflap.
-Dynamo lights.
-Tubus rear rack.
-Drop bars.
-501 or 531 or equivalent frame, from an old road bike, tourer or early rigid MTB. Nice to ride, but not too nice or attractive to wrong 'uns.
-Room for 700c x 37 winter tyres, if going down the 700c route.

I like the idea of hub gears and a chaincase too, for lower maintenance, but like the closer ratios and performance of Disreli gears. On the one hand I'd want the low maintenance of a dutch style bike, but want something more responsive and faster, less of a slug. Your build looks like its got the balance right, and most importantly, it looks nice too.

If you don't mind me asking, how much do you expect a similar build as yours to cost?

Regards,

Luke

[robc02]

The generator is available with a 3W output, or (for the Clogsters) a 2.4W output. I don't know about the 2.4W one, but IIRC the 3W one drags almost as much with the lights off as it does with them on. This is OK if you always ride in the dark, I suppose (the efficiency isn't that bad with the lghts on vs a lot of other generators BTW), or you don't worry about a few W of extra drag

During the winter months I leave my lights on in the day as well - saves me having to remember to switch them on and off . I recently acquired a Sturmey Archer FDD 2.4W, though I haven't built it into a wheel yet so can't comment further. I am currently using a Son Dynohub and rim brake, but might change to the FDD for the benefit of the drum. (I can't have a rear drum to go with it as I am using an FM hub which, of course, was never made with a drum )

[mig]

The generator is available with a 3W output, or (for the Clogsters) a 2.4W output. I don't know about the 2.4W one, but IIRC the 3W one drags almost as much with the lights off as it does with them on. This is OK if you always ride in the dark, I suppose (the efficiency isn't that bad with the lghts on vs a lot of other generators BTW), or you don't worry about a few W of extra drag

During the winter months I leave my lights on in the day as well - saves me having to remember to switch them on and off . I recently acquired a Sturmey Archer FDD 2.4W, though I haven't built it into a wheel yet so can't comment further. I am currently using a Son Dynohub and rim brake, but might change to the FDD for the benefit of the drum. (I can't have a rear drum to go with it as I am using an FM hub which, of course, was never made with a drum )

does this mean you want rid of the son dynohub wheel ?

[robc02]

does this mean you want rid of the son dynohub wheel ?

No, you can't have too many dynamo wheels - you never know when you might build another bike to use one .

[mig]

^^ darn it!!

[Brucey]

Re the build; the cost of the parts alone was over £400; this was even though some of the parts were used, and some ( the handlebars, brake levers, tyres, mudguards, rack) came from my chum's parts stash/old bike. The wheels were the single most expensive parts and cost about half the budget for parts. Needless to say all the little tweaks and mods cost little in parts, but plenty in time. I could have slung the bike together in a lot less than half the time it actually took.

Still, it turned out OK, even if there are always a few extra things that I didn't do.

For flatland commuting, a hub like an AM, or an FM might give nice close ratios.

The next bike I do will probably have a rear mounted hub generator; either another FG converted to five-speed, or a five-speed derailleur with hub generator rear hub.

cheers

[rjb]

The rear mech is a light action 'preselect' type one, and the jockey pulley bushings are fitted with lube ports. I have found that these rear mechs (like any other) can bend in a crash, but (unlike many others) they can nearly always be bent back again, because the parts that bend are made of steel. The shift quality is very good indeed, probably the best 6s shift I have ever used.

Hi Brucey, did you drill the jockey wheels to provide the lub port any chance of a pic? What do you lub them with? I usually end up being a member of the black hand gang when i dismantle mine and grease them. Iv'e got one that seams to be "persistantly squeaking" and no amount of lubing seams to cure it.

[Brucey]

the M5 fixing bolts were replaced with centre and cross-drilled stainless button heads. The jockey pulley bushings can be either cross-drilled (ideally) or notched at both ends. Some are too hard to drill, hence the end notching as an alternative.

The pulleys can be lubed using a grease gun with a pointed nozzle, or some meant for nipples also seal well enough on the convex button head shape. If the pullies are especially dirty they can be purged first with WD40 or GT85 (the centre drilling size -at the top- is chosen so that the 'straw' you get with WD40 is a snug fit). Aerosol motocycle chain grease can be as good as anything, and can be used as a one-shot purge/lube.

Brass centre bushings can be machined to fit the pullies perfectly; they last as long as anything else, and can of course be cross-drilled easily.

Basically once these ports are in place, there is no excuse for not giving the pullies a shot of lube every time the chain is done; it takes a few seconds to do the job, and no dirty digits need arise.

cheers