Supercommuter?

For discussions about bikes and equipment.
rjb
Posts: 7200
Joined: 11 Jan 2007, 10:25am
Location: Somerset (originally 60/70's Plymouth)

Re: Supercommuter?

Post by rjb »

Brucey wrote: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.


Thanks Brucey, a bit of lathe work coming my way. Like the idea of the brass bushings - i once made some from a stainless tube to fit conventional pulleys in a Mavic 840 when the roller bearings disintergrated. :(
At the last count:- Peugeot 531 pro, Dawes Discovery Tandem, Dawes Kingpin X3, Raleigh 20 stowaway, 1965 Moulton deluxe, Falcon K2 MTB dropped bar tourer, Rudge Bi frame folder, Longstaff trike conversion on a Giant XTC 840 :D
belgiangoth
Posts: 1657
Joined: 29 Mar 2007, 4:10pm

Re: Supercommuter?

Post by belgiangoth »

Hi Brucey,

Those there hub brakes, do they need special brazing? Do they do derailleur hubs with hub brakes? (if not, what are the back brakes?)
If I had a baby elephant, I would put it on a recumbent trike so that it would become invisible.
Brucey
Posts: 44520
Joined: 4 Jan 2012, 6:25pm

Re: Supercommuter?

Post by Brucey »

belgiangoth wrote:Hi Brucey,

Those there hub brakes, do they need special brazing? Do they do derailleur hubs with hub brakes? (if not, what are the back brakes?)


No special brazing required; the brakes come with simple clips for the reaction arms that fit around most forks and chainstays (~3/4" dia IIRC). In case you need a different size, others are available, but in fact it isn't the work of a genius to make something that would do the job. The front reaction arm slots into its clip and is therefore QD (although the hub itself is nutted). The rear reaction arm bolts into its clip so there is an extra bolt to remove when taking the wheel out.

The front hub is model X-FD 70mm drum brake
The rear hub is a model X-RD 70mm drum brake, for screw-on freewheel. This can be respaced down to ~120mm if necessary but comes spaced to 135mm.

Other front options include XL-FD -90mm drum, X-FDD 70mm drum with generator, XL-FDD 90mm drum with generator.

Another interesting rear hub is the X-RDC 70mm drum brake with 8/9speed compatible shimano fitting freehub. This hub runs on a total of four cartridge bearings and is of the hope/campag style where the freehub body runs on the axle, on its own bearings. There are double seals on the far driveside, and a lip seal into the pawl space. This hub has three pawls which engage simultaneously, and is allegedly strong enough for tandem use. It comes spaced to 135mm. I guess it could be respaced to 130mm but the wheel dish would not be so favourable.

With the exception of the X-RDC freehub bearings, the other bearings fitted to these hubs are mostly shielded rather than fully sealed. This is OK for the bearings inside the drum brake and on front hubs without a generator, but the expansion and contraction of air inside a generator hub is a likely source of water ingress trouble. On the rear X-RD hub I replaced the bearings with 2RS type ones from the start as I felt that water would be likely to get in otherwise.

hth

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
Brucey
Posts: 44520
Joined: 4 Jan 2012, 6:25pm

Re: Supercommuter?

Post by Brucey »

Update;

After a year or so of use it has mostly worked out as planned; a chain and a half's worth of wear, onto the second freewheel now.

Issues in use include;

- springtime water ingress into freewheel #2, (which was installed without suitably sticky grease in the right places)
- the (SA supplied) rubber pads beneath the reaction arm clips have perished already.
- all plated parts (that were not coated with waxoyl) that saw road spray have corroded to some extent in winter salt.
- the chain has come unshipped a couple of times
- the brake cable can come dislodged from the brake arm
- the brakes don't pull the bike up as quickly as you would like

The brake cable can get knocked in bike racks etc. It can get knocked loose, it seems. In tests, it is evident that if the brake is adjusted correctly (so that it comes on in the first 25% of cable pull) it is very difficult to dislodge the cable, and in fact it can't be pulled out without backing the cable adjuster out. So it isn't a problem if you don't park the bike against things that might knock it, and/or if you keep the brake adjusted.

The lack of absolute power is more of a concern. Part of the issue is the 700c wheel size, and part the weight distribution. The same brakes on a 26" wheeled bike with an upright riding position (more weight on the rear wheel) will pull up in about 3/4 of the distance (good discs might be better again). It might be that glazed pads are to blame, that the pads have not bedded in fully yet, or that they just are not powerful enough. Weirdly, once you get to a certain retardation value, it doesn't matter how hard you pull on the brake lever, the bike seemingly won't slow down any faster. It might be that an upgrade to the XL version of the front hub is a good idea, (which was always on the cards from day one... ). As it is, there is zero chance of going over the bars I suppose.

On the plus side the bike rides very well, and the frame geometry, the tyres rims etc give a nice feel to the bike. My chum (who also has a carbon road bike for weekend jaunts) describes the bike as 'pretty fast' in the context of a commuting bike.

So on the whole the bike has worked out as planned. A few wrinkles but nothing too alarming...

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
RJS
Posts: 280
Joined: 16 Feb 2013, 10:05pm
Location: Torbay

Re: Supercommuter?

Post by RJS »

Hi Brucey,
just reread this thread from the start, I noticed a similaritey to the colour of your bike with hub brakes to another of your bikes "featured" in another of your threads, a coincidence perhaps:roll:
Cheers, Rob.
robc02
Posts: 1824
Joined: 23 Apr 2009, 7:12pm
Location: Stafford

Re: Supercommuter?

Post by robc02 »

The lack of absolute power is more of a concern. Part of the issue is the 700c wheel size, and part the weight distribution. The same brakes on a 26" wheeled bike with an upright riding position (more weight on the rear wheel) will pull up in about 3/4 of the distance (good discs might be better again). It might be that glazed pads are to blame, that the pads have not bedded in fully yet, or that they just are not powerful enough. Weirdly, once you get to a certain retardation value, it doesn't matter how hard you pull on the brake lever, the bike seemingly won't slow down any faster.


Did you do the floating backplate mod discussed on another thread? I have been using my floating cam backplate on a 700c bike with 35mm tyres and the braking is excellent (70mm drums). I can progressively apply the back brake until the wheel locks - only just, though. Only the rear brake has the mod, the front brake is very effective as it is. I am using Tektro drop bar levers for V-brakes.

My own winter commuter - a drop bar hub geared (SAFM) bike - has Weinmann 730 brakes. I fitted them just to get the bike going, but, while they are a far cry from the drums mentioned above or dual pivots, they have proved surprisingly satisfactory in this undulating area of Staffordshire.
Brucey
Posts: 44520
Joined: 4 Jan 2012, 6:25pm

Re: Supercommuter?

Post by Brucey »

re. the floating backplate conversion; I have trialled this on another bike (another thread that needs an update) and I think it made a significant difference. I've just installed a similar conversion on my chum's supercommuter bike and...... it didn't make any difference, not to start with, anyway.

In a few week's time (once everything has had a chance to bed in) we shall review the situation...

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
Mr. Viking
Posts: 371
Joined: 6 Jun 2012, 9:29pm
Location: Liverpool

Re: Supercommuter?

Post by Mr. Viking »

Are they the 70mm brakes?

I have them on my commuter and they aren't the most powerful of brakes, especially when my all up weight can be up to 145kg. Mine took a while to bed in, but only 150 miles or so. I find they do pull the bike up in time, but I really have to try to get the rear wheel to lock. I always take it easy on hills

When you say the SA hub brakes have smooth bearings, I had always thought mine seemed good. My bikes generally roll fairly fast due to my weight, but I find that with these hubs in particular I quite often have to brake if I'm riding with someone and we both stop pedalling.

That bike does look great. I would love to take my components and put them on a lighter frame like that. i would keep the hub gears though, and I'm a bit large for skinny tyres.
Last edited by Mr. Viking on 1 Aug 2013, 11:04am, edited 1 time in total.
townbikemark
Posts: 282
Joined: 7 Jun 2013, 8:01am
Contact:

Re: Supercommuter?

Post by townbikemark »

Brucey wrote:This is the new bike I built.



Wow! You do this for a living right? Not to ask a stupid question, being newish to the forum...
stereotype nonconformance...unpigeonholable...

http://townbikemark.blogspot.co.uk/
Brucey
Posts: 44520
Joined: 4 Jan 2012, 6:25pm

Re: Supercommuter?

Post by Brucey »

for a living? -no, just for fun....

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
OnYourRight
Posts: 283
Joined: 30 Jun 2013, 8:53pm

Re: Supercommuter?

Post by OnYourRight »

Well-focused bicycles like this one are pleasurable to contemplate. And your many modifications are truly impressive, even reminding me of the old French constructeurs!

I’m sure many of us would like to see more and larger photos, if you have a chance to photograph it sometime.

Are the mudguards Chromoplastics? What saddle? And why did you opt for Open Sport rims, if there was any particular reason?
Brucey
Posts: 44520
Joined: 4 Jan 2012, 6:25pm

Re: Supercommuter?

Post by Brucey »

thank you for your kind words.

The mudguards are indeed chromoplastics, and were one of the few parts that could be re-used from the old bike. They seem pretty good to me, although the mudflaps are short, and aluminium piece in the centre will corrode in time.

The saddle is an OEM one as fitted to several 'Giant' models. It is nothing special, but was selected because has a good shape (if you are used to a racing saddle) and, perhaps most importantly for a utility bike, it has an outer cover which is waterproof.

The rims were selected because they are a middleweight stainless single eyelet, double-wall rim. Remember that the old rims had double eyelets, and the inner eyelet actually corroded right through, giving no support in the end. The single eyelet rim is about twice the wall thickness at the eyelet, thus making it (I hope) less likely to crack than a thinner walled rim. They built up very nicely, very true, with even spoke tension. I treated the rim internally with a corrosion proofing compound, and sealed the hollow section where the valve passes through the rim, to prevent water ingress. In the event of a prang, a new rim is about £22, i.e. about half the price of an open pro, and only 40 or 50 g heavier. In the absence of a prang, they should last for ever, corrosion aside. By contrast, on (say) a training bike with rim brakes, they might last two or three winters before the rim wears out. [also, if either wheel is scrapped for any reason, the rims can easily find a new home because they have a braking surface...]

My view is that unless you are carrying a load, a rim weighing 450-500g should be adequate for many purposes. The issues being rim wear, rim cost, rim interchangeability (ERD value), rim width, rim weight, rim strength (including resistance to corrosion). In older mavics , E2, MA2 through to Module 3 CD might do, the flaws being wear and corrosion resistance. Having said that the Module 3 CD rim had 2mm braking surfaces and weighed 500g. You can't buy a rim like that any more.... so much for progress.... :roll:

I reckon that a similar spec bike (with a few tweaks here and there) might make a nice audax/light touring machine, too. I'm not sure that every nook and cranny of this particular bike would bear very close scrutiny in fact; part of the mission was to make something that didn't look (at first glance) too much worth stealing.

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
mig
Posts: 2702
Joined: 19 Oct 2011, 9:39pm

Re: Supercommuter?

Post by mig »

i very much like this thread with its interesting & practical ideas.

was the raleigh 501 frame totally new? i ask as you blocked up the holes in the frame tubes - would this be recommended of an older frame? (so long as it was dry when they were blocked.) also what did you block them with please? and was the plastic film heated when applied to the frame?
Brucey
Posts: 44520
Joined: 4 Jan 2012, 6:25pm

Re: Supercommuter?

Post by Brucey »

the frame wasn't new, but was very lightly used. I previously had it built up as a 'mule' for experimenting with aero handlebars for a few years.

The plastic film is self-adhesive; just in case the film edges might lift, the edges are separately taped; not very pretty, but that wasn't on the list of objectives. To stop the tape from peeling, some zip ties might help.

The frame was bone dry inside and freshly waxoyled inside prior to covering over the holes, mostly using tape. Obviously if water gets/is inside, it is very bad news if all the holes are blocked.

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
Brucey
Posts: 44520
Joined: 4 Jan 2012, 6:25pm

Re: Supercommuter?

Post by Brucey »

update;

about eighteen months on, the bike has eaten another transmission (so it just about to get its fourth chain and third freewheel I think) but that, tyres and chain lubricant have been the only consumables thus far, as expected.

The floating brake plate conversion has finally taken effect, and the front brake -previously described as 'a bit weak'- now 'works pretty well without me pulling as hard as I can'. I shall see how it is for myself at some point.

BTW the possibility of breaking an axle in one of these rear hubs (screw on freewheel, but stronger than usual because of the spacers and the clamping action of the trapped cartridge bearings) has been mentioned. The proprietor of an LBS has been fitting these hubs (in various forms) for about 30 years now (and indeed uses them himself on his utility bike). He recently showed me a customer's bike that he built up about 25 years ago, in a vaguely similar style; a Raleigh 'Richmond' (531) frame, a 3x7 freewheel transmission, hub brakes, and flat bars. This bike has been used for a ~12 mile round trip commute for that time (big lad plus panniers) and has finally broken a rear axle. We estimate that the total mileage is between 50000 and 60000 miles. It is the only such axle breakage that I or the LBS proprietor has ever seen; (by contrast he sees conventional freewheel hubs with broken axles almost daily, certainly weekly). The axle broke just to the right of the RH cartridge bearing, and I thought the radius at that point was a little sharper than it could have been.

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
Post Reply