Folder with disc brakes?
 

Regular bike commuter in Portland, OR ... except I have a multimodal commute to the suburbs. It's getting to the point that I'm frequently having to let a train pass me by because all the bike spots are full, and our transit agency has gotten pretty strict about not letting on "extra" bikes except folders. I've been considering a folder for about a year, but today was the breaking point for me, as I had missed TWO trains on the way home this evening. And as it happened, as I got off the train that I finally DID make it onto, there was a Brompton owner unfolding his bike. I talked to him for a few minutes, and he kindly demonstrated the folding mechanism on his particular bike (pretty amazing) and said that he has NEVER missed a train because there wasn't room for his bike. OK, I'm sold.

Just one catch.

This is Portland, Oregon. It drizzles for half the year. My regular commute involves as much as 1000' of descending. I ride in a busy urban environment where panic stops are occasionally necessary. To me, that means disc brakes. I've been commuting with discs since 2004 and there is no way in heck I'm going back. For me this requirement is absolute. If anyone wants to take issue with it, I'm begging you in advance to please start a new thread and don't derail this one.

So for me that means no Bromptons, no Bike Fridays, no Dahons. It would be easy enough if a 26" folder were an option (Montague or Matrix would both be good) but our transit agency explicitly limits folding bikes to 20" wheels or smaller. I'm a total tire geek and uninterested in 16" or any oddball sizes like 18", so 20" it is. What are my choices? Near as I can tell:

• Swift folder, though it's a pretty expensive upgrade and pushes the bike over $1000. This is more than I'd like to spend, but I won't rule it out. I do like the idea of more "traditional" geometry also the 71 degree seat tube angle -- I'm a big believer in more "relaxed" seat positioning for reasons I won't go into at risk of derailing this thread. Also, can I assume I'm looking only at the steel Oregon version (which is available with disc tabs) and not the more affordable aluminum Xootr edition (which appears not to be)?
• Downtube. Not a deal-maker/breaker, but I do like the more compact fold, vs. the Swift. I have no need for full suspension (and am in the process of divesting my FS mountain bike, as I've discovered hardtails work just fine for me), so the "9" model (front suspension) looks right: disc tabs AND disc hubs front and rear. All I have to do is install the brakes and rotors already sitting in my parts box. And the price sure is right, even after adding in the rigid fork I would certainly want. Also, does anyone know the ETT length and angles on the Downtubes? This information seems awfully hard to come by, but I DO often ride 20+ miles in a day and need a bike that will fit me well enough to be comfortable on longer rides. Or does the stem ("mast?") adjust in a way that makes TT length less important?
• Uhhh ... Strida? I know, I'm reaching here. Not many choices. Seems cool (and has discs!) but maybe more of a toy? Especially since you can't get one with more than two gears: sorry, with my hills that's out of the question. The gear range of a typical 3-speed hub is my absolute minimum. But if the dropouts are long enough, maybe it can be upgraded to a gear hub? Another downside is its 45" length when folded may still make it difficult to travel with.
• Airnimal Rhino. Well out of my price range, I think. Correct me if I'm wrong.

Another requirement I have is the ability to fit a standard rack: I often drop off or pick up my young child at school with our Burley Piccolo trailercycle (which requires a proprietary rack), and expect to do so for several years yet to come. I understand that this may increase the folded size, but should still pass muster with the Transit Police. It looks like this should be doable on at least the Downtube or Swift without too much jerry-rigging.

One more feature that's not an absolute requirement but sure would be nice in a travel-capable bike would be the ability to handle moderate off-roading. Having a bike that can easily drop into a car trunk or go into an airline-legal bag suddenly opens up new riding opportunities, many of which would be on dirt. From everything I've read on this forum the Downtube has one of the most solid frames in the folding world and should be capable of light mountain biking with the right tires mounted. Maybe true of the Swift too? And even if Dahon made a disc 20"er, it sounds like maybe they're iffy for rugged terrain (or even curb drops, which I do on pretty much a daily basis)?

Are there other options in disc-equipped 20" folders I don't know about, or am I pretty much deciding between the $450 Downtube and the $1100-ish Swift?

Mercedes Benz has a folder that might be a good fit for you, but I doubt it will come within your levels of acceptability in regards to cost.

http://www.en-derin.com/wp-content/p...ding-bike2.jpg

Nothing will be as nice as the Downtube. I would consider the FS, since 20" wheels on high pressure tires are not 26" wheels with off road tires.

Just one catch: the size of a folded downtube can grow old really, really quick.

If I were you, I wouldn't think twice: Get a Brompton. I ride mine in mid traffic in Rio de Janeiro, Brazil. Your urban environment cannot be more panic stop demanding than Rio! It is hilly, it is wet, it is violent and it has over 11 million people with over 6 million tourists during summer. My Brompton had AMAZING stopping powers.

http://icaju.files.wordpress.com/200...tionamento.jpg

http://diariodorio.com/wp-content/up...de-janeiro.jpg




If you really feel the need of adding disk brakes to it, you are in Portland! You can always find a frame builder to add them to your Brompton. Best folding size, more than decent bike once unfolded, with the braking powers you want. Last time I quoted, it would cost 100 bucks of labor, 20 for the parts to be welded to the frame (I was adding V-Brakes though) and another 50 for the repainting.

http://farm3.static.flickr.com/2271/...82f1678d43.jpg


Good luck on your final decision.

I'm sure you could get disc brakes on a Bike Friday and if you're picky about geometry that'll be your only choice. Also, I wouldn't discount Dahon offhand: they make some nice bikes and I believe some have disc brakes.

Otherwise I'd definitely go with the Downtube because:
-There may be rack issues with the Swift due to the way it folds.
-Downtube already has the disc tabs.
-You're a discerning rider that puts in the miles. Save the $500 to upgrade the Downtube as you wear it out.
-The front suspension will be perfect for moderate offroading.

You can get some geometry measurements here:
http://downtube.com/Bike_Measurements/
The stem riser has adjustable height and the stem is adjustable around a circle.

However, I strongly suggest you not be so rigid about geometry because many of the geometry choices with 26"-27" wheels aren't handed down on stone tablets, but rather compromises relating to things like toe overlap, tube inventory (such as top tube lengths for different sizes), etc. Without these constraints you may find other geometries work just as well.

P.S. I know you said not to, but the fact is that there are also certain things which change with braking when you go to smaller wheels. All hub brakes work better with smaller wheels and you might find a drum brake sufficient.

It seems that Dahon makes a bike with stock hydraulic disc brakes, as well as a 8 speed IGH, front dynohub, lights, and a phone charger battery thing. http://us.dahon.com/bikes/1677/ios-xl Maybe a little steep in price, not sure about the standard rear rack. Anyhow another bike for you to check out.

Paint me surprised about your stance about disc brakes. I can lock up ALL my folding bikes' rim brakes. But OK, I won't argue or debate the point. But you aren't doing yourself any favours.

The Dahon Jetstream EX has disc brakes IIRC.

Pity about the poor Birdy support in the US - I think there is one available with disc brakes.

I think there are good conversion kits as well, which allow disc calipers to be fitted to forks that don't have welded fittings.

Steve Parry does a conversion :- Disc brake Brompton

I know you said not to derail the thread, but I have to agree with Chucky on this. I live in Glasgow, so I ride in the rain more than I don't, or so it seems. (I wonder which is wetter, Portland or Glasgow -- it must be close) I wasn't thrilled with rim brakes in the wet, so looked at different option on my Swift. I've got drums front and rear, and I'm perfectly happy with their performance. No difficulty locking up either wheel in the dry or wet. They've passed the wet, high speed, downhill, car-just-pulled-out-in-front-of-me test on 3 occasions with no trouble at all. The other advantage with drums on a folder is that everything is on the "inside" so nothing get whacked out of alignment on trains / buses whatnot. They feel different from discs to be sure, but I bet they stop a small wheeled bike just as quick, wet or dry. Not that I've tested this hypothesis. There might be a weight penalty, though.

I have a DT and I rarely fold it. However, when I have, it's kinda gangly. Not a neat tidy process. There could a danger of something striking your rotors and perhaps damaging them esp. if you're in a hurry.

So, OP, you want:
a folding bike for multi-modal transportation...
that's comfortable for 20 mile rides....
which absolutely must have disc brakes...
and has 20" (ISO406mm) wheels...
and no suspension...
that fits a Piccolo "Moose" rear rack...
but can pack into an airline legal case...
and handle off roading...
and $1000 is really too much to spend.

Did I get that?

And do you want a egg in your beer?

Only you know which of these requirements you will compromise on.

Me? I'd probably source a Raleigh Twenty and fit it with Fr and Rr Sturmey hubs and call it good - but that's just me.

Others following this thread might be entertained and amused by checking out the 20" wheel, disc equipped, folding Ice Sprint, Bernds, Jetstream EX and GoBike.

I'm pretty sure Bike Friday would build you a 20" bike with disc brakes. They have a MTB-ish version called the Pocket Llama. With the quick fold stem and seatmast it folds quickly.

Just a quick note here: there are no "dropouts" on the Strida frame or fork (hint: look at it in 3/4 view). Strida's are fitted with 14, 16 and 18 inch wheels - no models are cataloged with your required 20" wheels. And this is an opinion, but based on my personal multi-modal experiences I'd think the Strida's 45x20x9 folded dimensions would be easier to multi-modal with that the Swift's quick-fold 36.5x40x20.

Bike Friday shipped a disc brake equipped Tikit to a British customer.
As seen on his blog : http://combingmyhairinabrandnewstyle.wordpress.com

I'm passing through Eugene on my way home and had a Bike Friday Pocket Llama in my hands that had disc brakes. So it's no problem.

Good point! A decade ago all my mountain bike buds were spending $100-ish to have disc tabs welded to their bikes. Since the Brompton is steel, that would be an option. There is a Brompton dealer here in Portland (and lots of people who can do the welding), so I'll check it out. There would of course be the matter of acquiring an additional wheelset (I'm assuming the Brompton's stock wheels do not include disc hubs) and a new fork (I'm not going to have disc tabs welded onto a fork not designed for the forces of disc braking). Also would need to make sure that discs wouldn't interfere with the Brompton's fold.

Thanks for all the great words! Very helpful and informative. I will contact Bike Friday and ask them about discs. I can't find any mention of discs on their site, but of course they're a full-custom shop so maybe they can still do it. And (as with the steel Swift) if I'm going to be spending $1200+ it's nice to have a chunk of that going to local industry.

I agree with you about the upgrade path on the Downtube, and I'd expect to replace and upgrade quite a few of the parts. I'm used to building my bikes up from the frame with my choice of parts anyway, so I'm mostly concerned with the quality of the frame as opposed to the parts. And THANK YOU for the link to Downtube's geometry page. I didn't seem to find it from their home page. Biggest surprise to me is the ETT and wheelbase aren't really "shortened" at all compared to typical larger-wheeled bikes. Surprisingly "normal", really. No mention of the STA though: I might contact Downtube and ask them since that's such a critical measurement for me.

As for the Swift, it doesn't look like a rack would create any folding issues, since the front folds away from the rear triangle. Looks like clear sailing to me.

Unfortunately the Ios XL has 24" wheels. If it weren't for TriMet's 20" rule that could be a good compromise.

Sure enough. Unfortunately that bike is $2500 and full suspension. Thanks for the suggestion though.

Nice! So it's been done. Interesting fork.

Good to know. It looks like a clean fold (if not the smallest -- not that I'm too concerned with that). Is there more to it than just (1) dropping the saddle, (2) folding the stem and (3) pulling a pin or lever and flipping the front end around? Or is the awkwardness in dealing with the folded package?

You got it! I'll take the egg scrambled, please. :D

Well, yes and no. Admittedly my original post is a lot to crawl through and pick out which are absolute requirements and which are nice-to-haves, so let me clarify:

• Hard requirements: Folding bike for multi-model transport, disc brakes, 406mm wheels, ability to fit a standard non-proprietary rack, comfortable for 20 mile rides (i.e., not a toy).
• Preferred: no rear suspension, ability to pack in standard luggage, capability for light to moderate offroading, price under $1000.

The hard requirements are what I see as necessary for what is often a single day's commute: dropping my child (and trailerbike) off at school, riding downtown to catch the train to work, riding all the way back into the city after work without taking the train (climbing and descending 500-1000' depending on the route), then picking up my child and trailerbike at school and riding home.

As for the softer requirements, I could compromise on any of these if needed, though I'm not convinced that it is necessary. Rear suspension is generally contrary to my beliefs in simplicity and efficiency, but the right bike could override that. Packability for airline travel seems to go with the territory anyway as long as you don't mind some disassembly and reassembly (which I don't), so I'm all for it. For daily commuting I need a bike that can stand up to potholes and curb drops; any bike that can handle those should be able to handle gravel and smooth singletrack. And while I don't have a firm price I do expect value for my dollar. The Downtube is very attractive for the price alone, even factoring in parts upgrades (most of which I already own anyway). Going much over $1000 will require some re-budgeting but I could make it happen if I really think a bike costing -- say, $1200 -- is going to give me a ton of value over the Downtube. I don't have an absolute price ceiling but I would be very unlikely to want to go over $1600 or so.

It looks like there at least two, very different, bikes that meet my firm requirements (Swift and DT); most likely also BF if I talk to them about my needs. And even Brompton with some modifications, though that would likely make it too expensive. So I don't get the impression I'm asking for the impossible here. I do a wide variety of "types" of riding (most of which I'm not even asking this bike to do) and have limited room in my stable. Slacker copycat bikes and primadonna single-purpose bikes need not apply.

The 3-speed model is coming.
http://www.stridaforum.com/forum/vie...5&p=4969#p4969

Maybe we can see it at the bike show in Taiwan next month.

Actually, it is an OEM bike made by Jango.
http://www.jangobikes.com.tw/english/v9.html

I've looked at the Llama quite a few times on their site, and I'm sure there is something to be said for a bike that is purposely built for offroading. Although, again, it's not a hard requirement, I would consider spending a few hundred extra bucks to truly enable this capability. I will definitely contact BF.

Yeah, I'm not really serious about the Strida. Probably should have left it out, especially since as you point out it doesn't have 20" wheels. Would be fun for occasional use, but it's a pretty limited and inflexible platform, and I think I'd tire of riding it day after day.

OK, so in this thread I haven't addressed any of the comments questioning my desire for disc brakes. As promised I've started a new thread devoted to that very topic, and I've responded to your comments there. Have at it:

http://www.bikeforums.net/showthread...UT-disc-brakes!

I'm not sure what the issue is, but I remember people struggling with it and there's a reason why Xootr also sells a rack with a nonstandard-design as a Swift accessory. I think it may be that since the rear triangle pivots away from the seatpost there's no forward attachment spot for the rack (usually racks are attached near the dropouts and near the seat tube). Search the Swift thread for more info.

Ahh, yes I see. The rack would have to be clamped to the seatstays, not the seat clamp seat tube. It may also be that lowering the seatpost after folding may be interfered with by a rack, depending on its exact mounting, but I should be able to adjust the rack's angle to clear it. Definitely looks doable to me, though I will check the thread.

Some other considerations:
While the Downtube will be the closest to what you want out of the box and is cheapest, the font-suspension/disc fork weighs a ton (~4.5 pounds) and I don't think there are lighter replacements available (unless you have it custom made). So if weight is important to you then you're probably better off getting the BF.

Really depends on how much you want to spend, whether you prefer to do your own upgrades (BF only sells complete bikes...although they will upgrade to spec), and what you're looking for in the frame (lightness, fit, etc).

For your requirements, I would strongly suggest you save up a bit and go for quality which is more important in folders than big-wheelers. Folding bike joints suffer lots of stress and there is loads of "anecdotal" evidence that frame hinges will loosen up over time making the bike useless. I would try and avoid aluminium bikes with frame joints. IMHO they don't have the legs for long time heavy duty use.

If I were you I would place a Brompton top on my list and find a way to fit discs or hub brakes. Bromptons are pretty reasonable in price for the base models and I assume that the lack of wide gearing will not be a problem for you, given your experience. BF are of course good too, but have not as nice a fold, though I have no personal experience with them.

A Brompton S2L has 2 speeds, and if you fit a Schlumpf Speed Drive (perhaps Bruce could source one) you would end up with wide gearing. On my Birdy I find I am using 2 cassette cogs most of the time, and the Schlumpf up front. The cassette cogs are spaced about 10% in gear ratio.

Good point on the DT's fork. I would immediately want to upgrade that to a rigid one, and their own rigid fork doesn't appear to have disc tabs. I would have to find a 406mm-compatible disc fork somewhere -- and do the DTs have 100mm hub spacing in front, or narrower as is the case with many other folders? If 100mm, and if the BMX world has started embracing discs then it might be easy, but I don't think that's the case.

I've fired off an email to Yan at Downtube with these questions (and also asked about the seat tube angle).

You know, that's a really good point, and one that I hadn't considered. Aluminum frames definitely have a much more finite life than steel ones; for a full sized bike I'm not too concerned with that, but I suppose the longevity of aluminum frame joints might be seriously in doubt. I would be riding this bike a couple thousand miles a year.

Another question, while we're talking frame materials (uh-oh) would have to do with ride quality. I've been pleasantly surprised by the ride quality of the full-sized aluminum bikes I've ridden in recent years, but the Downtube's frame is REALLY beefy. Does it have a pretty harsh ride? Can I assume that the steel Swift or a Bike Friday (or Brompton) are considerably smoother? Not the biggest deal, but if there is a significant difference I'll factor that into my decision.

My local dealer quotes a Brompton with 6-speed gearing (3-speed internally geared hub by 2-speed Brompton derailer) at $1400. As long as I have a disc up front, a drum should be adequate in back and then I wouldn't have to modify the actual frame. But I'm sure by the time I get a new wheelset and fork, I'm still pushing up near the $2000 mark.

Which makes it (probably) more expensive than a locally made Swift or Bike Friday. I hear a lot of great buzz about the Brompton -- but is there any great advantage to them other than the super-compact fold? Frankly, as long as the bike folds in half that's good enough for me to get it on the train, and I don't mind breaking out the tools to dismantle it for travel.