Cycling UK Forum

Hi all!

I'm currently at the start of my second week touring from Rocamadour to Munch via the Alps.

Originally I had planned to get to Chamonix from Albertville; I'm currently in Voiron, going to Chambery tomorrow. I checked the elevation profile from Albertville to Chamonix and realized it's a bit much for me in one day on a loaded bike. Then I noticed that going to Chamonix from Annecy was gentler.

What have folks here done when heading into the Alps from this region?

- Tim

531colin wrote:Dropping the top tube can't influence the steering.
As for structural failure at the top of the head tube......
I've seen 1930s/1940s lugless Higgins Ultralite head tubes "spread" where the headset fits.....because its lugless, and the way to make a steel frame light is to use less metal.......
But I can't think of anything else.....anybody?

I asked the fellow who's building my frame about this, and he said something about increased stress at the joins, especially where the top tube meets the seat tube, if the joint at the head tube is lowered, and also that the closer the top tube/head tube joint is to the down tube/head tube joint, the more stress there is... something along those lines, I can't remember the terminology he used.

He said it wasn't very significant, but it was did change the stresses on the bike negatively.

- Tim

531colin wrote:As I posted originally, the small sizes have a dropped top tube. Look at the bike stood up against the green stone wall, I think its probably the second-smallest bike.

Got it - I was looking for that configuration regardless of size (and wasn't sure about the actual size of each of the bikes pictured).

So I take it you don't think there's anything sacrificed by lowering the top tube joint? No less strong of a bike, worse steering or anything?

- Tim

the snail wrote:The image of the elan at top left under the main pic looks like the head tube extends above the top tube

Weird, some of them do and some of them don't; I wonder if that is related to the official bike "size".

- Tim

531colin wrote:Go to Spa Cycles website and look at Elan....that's a Ti frame.....the small sizes have both seat tubes and head tubes extended above the top tube.....you can call that a dropped top tube, if you like, and its for standover for short legs.
Just to show alls fair in love and bicycles, the biggest size is limited by the available length of steerer in carbon forks.

I took a look - this? https://www.spacycles.co.uk/m1b0s21p355 ... -triple%29

I doesn't look like what we're talking about, that I can see - it seems to have a bunch of spacers. The "Ti Tourer" looks more like what you're describing, but that, too, looks like it has a bunch of spacers:

https://www.spacycles.co.uk/m1b0s21p255 ... -Ti-Tourer

Do you have a link for what you're describing?

- Tim

peetee wrote:I think most builders of steel bikes avoid sloping top tubes on lugged frames because of the difficulty of sourcing lugs with the required angles.

Just for the record, the bike I'm having built is titanium, so I couldn't have lugs on it even if I wanted to (unless they've found a new technique for adding lugs to titanium frames - at least, my builder doesn't do that). So that's not a concern.

- Tim

Hey again folks...

So as mentioned elsewhere, I'm having a custom touring bike built for me.

The builder is making it with a quite long head tube and about 13 degrees of slope in the top tube, so that I can have the handlebars high for comfort, but still be able to stand over the bike.

On another discussion on another site of handlebar height and sloping top tubes (which I can't find anymore), the topic came around to bikes built with long head tubes, but with quite a bit of head tube extending above the top tube/head tube joint; this way, you could have something close to a horizontal top tube, but still have handlebars mounted high up without a lot of spacers, tall quill stem, or extreme-angled threadless stem. Someone even posted a picture of such a bike (I think it was also a custom job).

It's too late to ask the builder to do that (he didn't seem to want to do that to the extent I wanted; he lowered the joint about a cm, but not much more).

Has anyone here ridden such a bike? Are there disadvantages (besides it looking kind of funny) to that design?

- Tim

Brucey wrote:some comments on nomenclature;

a) it is '650B' not '650b'

b) '650x33' is meaningless. '650Bx33' (or similar) has some meaning rather than none.

c) There are 650A, 650B, and 650C rims sizes and they are all different.

d) The 650A size is a French version of 26 x 1-3/8", similarly 650B = 26 x 1-1/2", and 650C = 26 x 1-3/4". The rim BSDs are 590, 584 and 571mm respectively.

e) The French standards are no longer maintained. To avoid confusion it is best to use the ISO tyre sizes, eg xx-590, xx-584, xx-571 etc.

cheers

Sure sure. For all references to "650b" or "650B" or whatever you prefer, in anything I've posted here, please translate to "X-584" with the "X" being whatever tire width I'm talking about.

- Tim

GELL71 wrote:I have a set of Donnelly MXP (650x33) on my cannondale slate. They're folding and tubeless. A bit heavy going for a touring bike, but they're lightweight and supple, so might not be too heavy on the resistance. They also appear to be pretty bullet proof. I've done a few flinty, rocky rides, with virtually no signs of damage.
I know canyon use 650b for their smaller frame size road bikes, it might be worth checking out what tyres they fit as standard.

rgds
Guy

The rims I got take tubes (unless there's some way of running tubeless tires on rims that normally take tubes); I haven't really looked into the tubeless world, tho'.

I'm talking with the guy who's building my wheels; he works for Rivendell, and says they have a few they use on their bikes that can work (nothing like the selection on 700c, but at least it's a few extra options for me). I'd still like to be able to get my Schwalbe Marathon tires at 32-584, but if that happens, it'll be far in the future I think.

I'll check into Canyon, in any case, thanks!

- Tim

PhilD28 wrote:You seem to be of the opinion that a 32mm section tyre will be faster than a 38mm or 42. This has been de bunked many times in the last 5 years. If you read some of the Bicycle Quarterly articles on testing different section tyres you might change your mind. Even road racers use 25mm or 28 mm section tyres-instead of 23 these days.

For me it's not just an opinion; when I first got my older touring bikes, they both came with something between 38mm and 44mm tires. I rode them for awhile, both loaded and unloaded, and then switched to 32mm on both. In my subjective experience, it felt faster and more responsive and less draggy when using the 32mm.

I've definitely read about tire width mattering less, and even went with 25mm tires for my new road bike based on that. But I get a feeling there's a "sweet spot/region" where tire size matters less, but at some point (and with some load sizes), the "contact patch" grows enough to produce more drag. Again, that's been my subjective experience with wider tires on a touring bike.

YMMV (and it apparently has). I haven't done as much mileage as you, at least on tours; maybe 5000 miles. I don't know how much the bike-shop owners I spoke with have done; the two I know best have done quite a bit of touring, though we didn't discuss tire width much, more about the viability of 650b wheels in the future. None of them told me I should be using any given width tire, tho'.

- Tim

cycle tramp wrote:

tbessie wrote:Hey all...

So I'm having my dream touring bike built; I decided to go for 650b wheels, as 1) this is for an S&S coupled bike, so it'll be slightly easier to fit in the case without as much playing with the parts, and 2) it seems like 26" will be slowly dying while 650b will be slowly taking its place.

- Tim

I remember my father being told that the new 700c wheel size would replace the old 27 x 1 1/8 and generally it did... however you can still get 27 × 1 1/8 tyres even now... i suspect the 559 wheel size might be with us slightly longer than then the bike journalists suspect.

Don't forget to show photographs of your bicycle!

Yeah, given the number of rims and tires currently available, it might have been smarter to go with 559 if I wanted a smaller wheel for packing purposes. The reason I went to 584 was based on articles and forum discussions I'd read, and advice from local bike shops. In the end, it was a toss-up and a hope. We'll see if it ends up paying off. :-/

I'll certainly post a photo of the new bike when it's ready!

This is part of a project of mine to get rid of the 1 road riding and 2 touring bikes I own, and replace them with "dream bikes" of the same type (well, only 1 touring bike). I've gotten rid of the road bike and one of the touring bikes, and will sell what's left of the other touring bike once the new touring bike is done.

Here's the "dream road bike" I got - first, the builder's own pix (my last name's "Bessie", thus the "Bessiematic" on the top tube):

https://www.flickr.com/photos/fireflybi ... 7860400401

... and mine of the finished bike:

https://photos.app.goo.gl/F3rVS7lwp9qE6V7u2

- Tim

le.voyageur wrote:Schwalbe also do at least one tyre that comes up at 35mm as it's 1.35"

Yeah, not a whole lot, tho', and not touring specific. Here's what they have under 40mm:

https://www.schwalbetires.com/node/2366

https://www.schwalbetires.com/node/282

https://www.schwalbetires.com/node/3026

https://www.schwalbetires.com/node/2956

That last one's the closest to something I'd want, and it's 37mm.

- Tim

tbessie wrote:

Brucey wrote:only tyres that are listed as xx-584 (in ISO size designation) will fit 650B rims. 584mm is the bead seat diameter of the rim.

Yeah, I read several articles on the subject after your earlier post, and got schooled. Thanks for all the continuing education.

... So there are a few choices. I expect you will find a -584 tyre that will suit you alright, but if you don't there may be another way with that frameset, (provided it doesn't have cantilever brake bosses, which would make changing rim size problematic).

BTW I have a folding bike that uses 559 wheels (no choice, cantilever brakes fitted) and it has ~32mm tyres on it. The rolling diameter of the wheels is ~24-1/2" or so, so the bike packs down small. I expect to be able to buy good tyres in that (niche) size for at least five or ten years to come, maybe longer. As it happens the frame will accept tyres up to 50mm quite happily so I am unlikely to get stuck even if (as pessimists would have it) in time, tyres for the 559mm rim become less plentiful; I will always be able to buy something.....

Well, given this is a custom frame, I got to choose what sized tired I wanted it to allow, what size mudguards, etc. I had told the builder that the largest tire I likely would use would be 38mm, so supposedly that's what he's building. The last communication we had, he had cut the tubes and was going to start welding soon. I emailed him my issues with tire sizes, and asked his advice. I prefer 32mm because the kind of touring I do, I prefer low rolling resistance to cushyness, even if rolling resistance probably isn't that important with a fully loaded bike.

In any case, I doubt I'll be able to swap out wheels. And I put in an order last week for some rather nice 650b wheels (Velocity Atlas rims, Phil Wood hubs), which will end up costing around $1250... so I'm rather invested in the whole 650b thing. I don't think I'll have any problems outfitting it for this year's tour, and for several years to come; however, many years down the road, I'm not sure sure. I do like the ability to saunter into a bike shop anywhere in the western world and get tires, rims, etc. (tho', of course, for that I should have gotten a bike built around a 700c rim).

So I got what I got, I can't really make any changes in it, it's rather all set in stone by this point. I'll just use the bike for some years, and if I find it being a pain to get tires and other bits for it, some time in the future I might switch back to 700c (or something else if some other smaller wheel size becomes a bigger standard than the current 650b resurgence).

As for brakes, it's going to have this modern take on center-pull brakes:

https://paulcomp.com/shop/components/racer/

They mount in a non-standard place, so going forward I'll always have to use these ones (or ones that mount in that place). I'm hoping that this particular brake is available until I'm done with the bike.

- Tim

Brucey wrote:only tyres that are listed as xx-584 (in ISO size designation) will fit 650B rims. 584mm is the bead seat diameter of the rim.

Yeah, I read several articles on the subject after your earlier post, and got schooled. Thanks for all the continuing education.

... So there are a few choices. I expect you will find a -584 tyre that will suit you alright, but if you don't there may be another way with that frameset, (provided it doesn't have cantilever brake bosses, which would make changing rim size problematic).

BTW I have a folding bike that uses 559 wheels (no choice, cantilever brakes fitted) and it has ~32mm tyres on it. The rolling diameter of the wheels is ~24-1/2" or so, so the bike packs down small. I expect to be able to buy good tyres in that (niche) size for at least five or ten years to come, maybe longer. As it happens the frame will accept tyres up to 50mm quite happily so I am unlikely to get stuck even if (as pessimists would have it) in time, tyres for the 559mm rim become less plentiful; I will always be able to buy something.....

Well, given this is a custom frame, I got to choose what sized tired I wanted it to allow, what size mudguards, etc. I had told the builder that the largest tire I likely would use would be 38mm, so supposedly that's what he's building. The last communication we had, he had cut the tubes and was going to start welding soon. I emailed him my issues with tire sizes, and asked his advice. I prefer 32mm because the kind of touring I do, I prefer low rolling resistance to cushyness, even if rolling resistance probably isn't that important with a fully loaded bike.

In any case, I doubt I'll be able to swap out wheels. And I put in an order last week for some rather nice 650b wheels (Velocity Atlas rims, Phil Wood hubs), which will end up costing around $1250... so I'm rather invested in the whole 650b thing. I don't think I'll have any problems outfitting it for this year's tour, and for several years to come; however, many years down the road, I'm not sure sure. I do like the ability to saunter into a bike shop anywhere in the western world and get tires, rims, etc. (tho', of course, for that I should have gotten a bike built around a 700c rim).

So I got what I got, I can't really make any changes in it, it's rather all set in stone by this point. I'll just use the bike for some years, and if I find it being a pain to get tires and other bits for it, some time in the future I might switch back to 700c (or something else if some other smaller wheel size becomes a bigger standard than the current 650b resurgence).

- Tim

Brucey wrote:... lots of stuff snipp'ed ...
If you want to buy 32mm tyres easily, maybe a different rim size would have been a better idea; 700C (622mm rim) would have been a good choice, however nothing is certain.... I am told that once upon a time (in the 1950s) the most popular tyre size in English lightweight bikes was 26 x 1-1/4" (32-597). Bikes commonly were still being sold with those size rims and tyres on about 30 years ago, and it was one of the original Dunlop sizes (like 26 x 1-1/2"). However now you will struggle to find any tyres or rims in that size. In the meantime the 27" size (630mm rim) has basically come and gone too.

Thanks for all the info! Very interesting!

Can tires with other ETRTO sizes also fit 650b rims? Or only ones that are so designated?

As for getting a more common rim for 32mm tires - well, as I mentioned, I chose this size for several specific reasons, so that's a non-starter. I'm stuck with this. If, in several years or more, I find that 650b rims and tires are disappearing, either I'll stock up on a bunch of tires, or have to get another bike made; I hope it doesn't happen.

Before I made this choice, I talked with a lot of bike shop owners and bike builders, and they said it would be better to get a 650b bike than a 26" bike, as they thought 26" was going to die out. But who knows if that'll happen. In any case, if I didn't care about smaller wheels in order to fit more easily into the S&S case, I would have gone with a 700c bike, since that's by far the most common.

So... oh well.

Meanwhile, I found a few 38mm tires out there that will work; Schwalbe still doesn't have much in that size for 650b, mostly 44mm and bigger.

I'm thinking I'll likely end up getting the Panaracer RibBMo in 38mm.

https://www.panaracer.com/lineup/urban_touring.html

As for my 32mm-34mm fenders, I hope that more tires become available so I can use 'em; otherwise, I'll have to get bigger fenders.

- Tim