Compression and rebound control are more important to me. Honestly I would never use the lockout feature.

Thanks
Yan

Compression & rebound are important to me too, but lockout feature isn't a great complication to producer that will help a lot pedaling in long trip on flat streets. I'm I wrong?

I'm sure you are right for your needs. However I feel differently. Aluminum is a stiff metal, when you shorten the frame and use smaller triangles it gets stiffer, and the small wheels are super stiff making everything worse.

I'm 6' 200ish lbs and I prefer suspension all the time.

Thanks
Yan

I agree with Yan - I want suspension, all the time. The design of the Birdy suspension is good, there's minimal bob when riding along even with fairly high effort. Ride quality is similar to my wife's Moulton TSR.

The only scenario where I could see lockout being useful is if you like to stand and hammer a lot - any suspension bike will bob in that scenario because your whole body weight is bouncing up and down. I guess standing vs. sitting is a matter of personal preference, but if you look at professional racers they tend to sit most of the time (except for sprints) so standing is clearly not needed for performance.

I raced MTB's and I was taught to never stand. Once you stand your rear wheel is likely to loose traction and spin freely in the trails.

Thanks
Yan

That is the standard road bike theory on suspension, which is 1990s. Well designed suspension that takes into account power induced
suspension compression where the suspension pivot is close to the upper chain line do not need to be locked out. The Birdy and Downtube FS9 address this by moving the pivot up toward the chainline, the Brompton, Moulton do not.

The benefit of suspension on small wheels is to cut down on the harshness of small stiff frames and wheels. Putting a lockout on defeats the whole purpose, may as well go rigid.

Yeah you guys have convinced me with great arguments. So I come back to foldingdroid question: are custom made suspensions better than the original ones? Which are to be preferred?

P.S.: next week I would like to deal with a vendor for a test BD3 speed at €1.770 than I'll start the tuning time concerning weight and other stuffs like maybe a Gates carbon drive (I know this would mean to change the great Ultegra).

I doubt it's possible to retro fit a belt drive system to the Birdy as I'm sure it needs an auxiliary tensioner to cope with the requirements of the folding process.

Tensioner is not a big problem, cause exist on the nexus birdy and could be adapted.

About 10 years ago the was a Birdy Green available in Europe that had belt drive but it was discontinued fairly quickly- might be worth investigating why before you commit to any expenditures.

I've posted some notes on my recent plane and train (and city riding) travels with my Birdy in my blog:

https://hasbrouck.org/blog/archives/002276.html

Turkish Airlines is still offering the trans-Atlantic sale fares that allow two pieces of checked baggage at no extra charge that I mention in that post. This means you can check both a folding bike and a large backpack (or set of panniers) without any checked baggage fee.

Belt drives require fixed chainstays. The rear suspension on a Birdy implies that the chainstay length varies, hence the problem.

Thanks,
Yan

I rather wonder why people are enamored of belt drives. Belt drives have been available here in Japan on various types of bikes for decades, and even though they are not particularly expensive, they still have not managed to catch on.

One of the things I most like about the Birdy is it's ability to use standard components. I have an XTR 11 speed driveline on mine, with a Dura Ace crankset and front derailleur, for a total of 22 speeds. And it is all bolt-on, no fabrication or modification. And if and when Shimano comes up with a 12 speed system, it will likely bolt onto the Birdy as easy as the 8, 9, 10, and 11 speed parts do.

I also like that converting to 20" wheels involves nothing more than attaching the wheels, and either extending the brake posts with adapters, or getting brakes with longer arms.

As for the suspension, here in Japan there are various types available, but pneumatic and hydraulic. These are a bit expensive, about $200 each for the front and back. For myself, the stock springs and elastomers are completely adequate. They aren't high on the cool factor, but they are perfect for the job.

The only advantage to the belt drive would be to keep your hands and bike bag clean when folding and unfolding your bike.

With your 2X11 system, do you have any idea of the gear range as expressed in gear inches?

What is the better V brakes can you recommend for Birdy? Will Magura rim brakes will fit on a Birdy?

I use Shimano XTR v-brakes, no complaints. For 20" wheels I need adapters, but brakes with longer arms and slots work fine without adapters. The only problem with the longer arms and slots is that when the brake shoe is moved closer toward the end of the brake arms, the less leverage you have, which means increased braking effort. In a pinch, you can use your OEM brakes by moving the pads to the end of the slots, and turning them so the ends can grab the rim. I don't recommend doing this unless the alternative is no brakes at all.

With your 2X11 system, do you have any idea of the gear range as expressed in gear inches?

The range is from 17" to 85" (remember my Birdy has 20" wheels). It is quite adequate for just about anything, though the rear cassette looks the size of a dinner plate. There are some steep hills here in Japan, no need for me to get out of the saddle to climb them. The only difficulty I had was finding a front derailleur adapter which fit correctly. There is not a lot of space between the swingarm and the chain rings, so placement is critical. As I was using an Ultegra road hub, a spacer is needed for the 11 speed XTR cassette to fit properly, but it was included in the package.

Thank you Sangetsu!

Birdy Disk brakes: hydraulic or cable actuated?
 

I've read references to current model Birdy disk brakes being hydraulic... and other references to them being cable driven. Is one correct and the other wrong or is the disk brake chosen a function of marketer preference?

If you look at the manufacturer's website, you'll see that they are all listed as hydraulic:
https://www.r-m.de/en-us/folding-bike/birdy/

But Pacific Cycles (which I think is the current manufacturer of Birdy) lists the the bike as supplied with an Avid BB 7 Disc brake (which I think is mechanical rather than hydraulic). Same for NYCEwheels (new york). Bfold lists TRP Spyre Disc Brake (also mechanical, I think). That's why I was/am confused!

I suspect they supply different set-ups for different markets areas.

Are you referring to this type of brake adapter?

http://bicyclebuysell.com/images/upl...0781481-52.jpg

Besides swapping out the wheels and installing the adapters, are there any other adjustments needed?

I'm very curious: how has the use of 20" wheels affected the fold?

These are not exactly the same ones that I use, but they will work. The cleanest adapters are the old Suntour Superbe type which adapted short-reach caliper brakes designed for 700c wheels for use on bikes with 27" wheels, though these adapters are very hard to find nowadays. If the adapters are expensive, it may be cheaper just to convert your v-brakes to the type which have longer slots. If price is no object, the Paul Motolite brakes work very well. My local shop sells the longer style v-brake arms, the entire kit, front and rear, is only $25. No special adjustments are necessary.

With the 20" wheels the fold is not as tight, though I can still fit the bike inside my Birdy carrying bag.

The 20" conversion makes an obvious difference in speed, handling, and run-down. And the larger wheels give me more clearance for my medium cage derailleur.

$25 is a fantastic deal for the entire kit! I've tried looking for Ridea long reach V brakes locally but no such luck so far. The adapters are available on eBay, but they're roughly the same price as your entire kits.

Conversion to 20" wheels make a lot of sense. When I picked up my banged up old Birdy, that thing looked like it was using its derailleur as a kickstand. I guess a compromised fold is worth the change.

Riese and Müller is the inventor of the Birdy and also the manufacturer of the models for the western parts of the world. The frames are produced by pacific cycle and they produce and sell the Birdy in Asia. Specs may be different between the two as the product lines are independent from each other apart from using the same frame and the same name. The deal with Pacific Cycles regarding manufacturing and market-areas dates from the very beginning of the Birdy in the nineties when they were looking for some funding to start production and Pacific Cycles stepped in to help them with production of the frames, getting the right to serve the asian market with Birdies in exchange.

So depending on in which area of the world you are living Birdies may be speced differently.

Perfect! thank you for clearing up my confusion.

I hope you guys don't mind me posting in here, but I figured this might be of some interest for those of you who live in the NYC area. We have been working with Riese & Müller in Germany to bring their bikes to the states and we're going to have a party on April 8th. Heiko Müller, the co-founder of Riese & Müller will be there to talk about the history of the company along with his wife Dr. Sandra Wolf, the Brand Specialist & Managing Director of R&M. I added it to the calendar section, but I figured I would add it here as well. I hope to see some of you there :)

I'm not able to post links, but the event is April 8th from 6-9pm at Propel - 134 Flushing Ave, Brooklyn, NY, 11205

Do you think it's possible to get a Birdy (not classic) to 8kg or under? I really like Birdys, the only reason I don't own one is weight.

Anyone know the weight of the frame and fork alone?

I think you would have to go single speed and jokacks to get near 8kg. About 10.5 basic bike.
Birdie is one of the lightest folding bikes in mass production.