bike.gang.uk

You might find this interesting, or should I post it to Brompton thread?

foldingdroid

It's a Birmpton!

desastar

Well, I can confirm the handlepost stem from the monocoque fits the classic frame perfectly! The carbon seatpost on the other hand looks good but not practical for a folding bike where it needs to be raised and lowered repeatedly, the clear coating is coming off at an alarming rate. As I can't have the seatpost too tight, being carbon, it slides down after a while... Happy with the result nonetheless.

bhkyte

There is about 0.5mm difference between the seatpost tube between the classic and monocoqope. It means that if I swop seatpost between bikes I need to adjust the QR a couple of turns.

desastar

Is that so? That explains a lot of things. The trouble with a couple more turns of the QR, it makes folding a bit stiffer.

foldingdroid

You got a nice and clean birdy desastar.

desastar

thanks!

Final mod would be a set of 20" wheels. However I'll need to use skinny tyres which wouldn't be as durable.

mkatz

I'm "late" to this thread. I recently test-rode a birdy (Urban Bike Fitters in Fremont, California) and was impressed by the smooth ride over somewhat rough pavement. I'm seriously considering buying one. Before I commit, I'd appreciate comments anyone might have with respect to experience with the Rolloff model...

BloomingtonFPV

I had a chance to ride the non-Rohloff version in Berlin last summer, and I found it to be very responsive, even lively.

I decided to stay with my Giant Expressway folder, which I retrofitted with a chain-based Rohloff. I absolutely ADORE my hub. I've had zero problems with it, it is easy to shift when moving or stopped, and it just works.

Some gears are a little louder than others, which does serve to help you know which gear it is in. You also have to just slightly back off the pressure when shifting, but you don't have to stop the pedals. But the 14 linearly-spaced gears are just a joy to ride.

I'd recommend testing the birdy and if you like the general ride I'd definitely recommend the Rohloff.

darukhan

I'm toying with the idea of reducing the number of speeds my Birdy has as a winter project. My Birdy currently has a Sram Dual Drive 3 x 8 hub (with a Sram 11-32) cassette. When paired with the 58 tooth chainring I have on it, the bike is capable of a ridiculously massive gear inch range which is fun, but ultimately, it's a setup that is completely unnecessary. (...I mean, I can't even use the top gear unless I'm going downhill.... but when I can, I easily can hit 34mph! Going uphill is ridiculously easy spinning out in lowgear!)

So... with my current gearing, I can tackle virtually any hill up or down and have a multitude of speed options in the flats.... HOWEVER.... since my Birdy is used 99% of the time for commuting to work, I find myself ever only using THREE gears!

This has me thinking... "simplify".

I'm considering actually going in the complete opposite direction and dropping my number of gears to match the purpose of this bike, and if I'm going to change the hub, why not consider losing the excess cabling and consider a coaster brake.

QUESTIONS FOR YOU ALL!
1) I'm curious if anyone has ever tried using a coaster brake hub (any speed... single, two, three, seven, etc.) on their Birdy?
2) If so, what was your experiences with a coaster hub on a Birdy?

yangmusa

An indirect answer to your question: when I had a Birdy, it had a 9-speed Capreo setup. I think the gear-range was roughly 30"-90". I went loaded touring on it (tent, food, everything!) in California (think hills!). Although I occasionally wished for lower gears, overall I thought it was a great compromise setup for lightness/simplicity.

So - for your intended usage, it sounds like a good idea. On the other hand, there's no real downside to riding a 3x8 setup to work, and a not inconsiderable investment in changing it.. Depends how strongly you feel about it

yangmusa

Oh wow! Yes, consider me interested!

mconlonx

I noticed that the Dual Drive hub I got had a cassette/freewheel(?) with a much smaller range than the 8sp wheel it replaced, with closer ratios. So while there was still some ratio overlap, I came to appreciate the tighter ratios.

I never tried a coaster brake, but I imagine it would be problematic on a number of fronts.

OLD of the hub -- usually coaster brake hubs are not as wide as standard hub sizes, although many, especially Sturmey-Archer hubs can be found in standard widths.

Chain line -- not sure how it would work out and less room to play with on a folder in order to make it work while maintaining full functionality of the fold.

Chain tension -- the variable chain tension with the suspension, not to mention folding nature of the bike does not lend itself well with a system like a coaster brake setup on which a fixed chain length is preferred. Although an adjustable strut to replace the the rear elastomer might elegantly solve the tension and variable length issues, it would complicate the fold process and you'd lose rear suspension, one of the nicer characteristics of the bike. Also, with a coaster brake, a chain tensioner or derailleur is out.

ehasbrouck

I bought a used "classic" Birdy (pre-2003) on Craigslist. The price was right, and I like it a lot. I had ridden a borrowed newer-model Birdy before, and loved the ride. I've also test ridden a Bike Friday and some other folders, but hate the rough ride of a small-wheeled bike without a suspension, especially in front.

The Birdy I got has no fenders/mudguards or rack. I don't need a rack, but I would like fenders/mudguards.

The local Birdy dealers (Warm Planet in San Francisco and Urban Bike Fitters in Fremont, CA, USA) say the classic Birdy models lack the mounting points for the current Birdy-specific racks or fenders.

(1) Does anyone know a currently-available fender-mudguard set that will fit a classic Birdy? I'm wiling to do *some* hacking to make it fit, but I'm not an expect and don't want to drill the frame.

(2) Once upon a time, fenders/mudguards were made for the classic Birdy. Somewhere there is probably a NOS set collecting dust in the back of a shop. Does anyone know of a Birdy dealer that might be likely to have one?

(3) I'm in the USA, but I'm going to be in Amsterdam and Brussels next month, probably with my Birdy. Can anyone recommend a shop in either of those cities that sells a lot of Birdys, or that has a large variety of folding bike accessories and might have something that could be made to fit my older Birdy?

(I've posted a separate message about the size of a folded classic Birdy as airline luggage, slightly related only to the extent that fenders/mudguards might slightly increase the folded dimensions.)

Thanks for any tips, experience, or advice.

Edward

yangmusa

I only flew with my Birdy once, and I borrowed a friend's Bike Friday suitcase to do it. It was a hard-side Samsonite, around 30" IIRC. There was a lot of room for the bike, but I had to remove both wheels and on my particular model the stem was not adjustable so I had to take the handlebars off. All in all, not too much trouble to pack it, though my Brompton has it beat (no packing required - fold and put in case!)

ehasbrouck

I'd like to take my Birdy a checked airline luggage without paying an extra fee.

The standard maximum for checked airline baggage is 62" (158 cm) length + width + height.

I have a pre-2003 "classic" Birdy with no fenders/mudguards and no rack. Folded, it seems to be *slightly* more than 62" total, no matter how I measure, even if I put it in a thin bag that doesn't increase the size.

Have others taken a Birdy-in-a-bag as airline luggage? Have airlines measured it? if they have, have you been charged extra for it as an oversized item?

Or is there some way to get it within 62" by partial disassembly, beyond normal folding?

Thanks for any experience or tips you can share,

Edward

yangmusa

I was not charged for flying with my Birdy, it was in a standard case.

Here are more experiences, with pictures!
https://www.bikeforums.net/folding-bi...ight-case.html

So in answer to your question - yes, it's easy to make the Birdy fit in a case smaller than 62"!

bhkyte

Take both wheels off the birdie and fold back rear frame and fork tie back with bugge and its really small. I would have though easy to pack.

helium77

Hi guys, got a question about the birdy that need some help here. The lever that is used to lock the stem upright keeps undoing itself. It seems each time after barely 10 mins of cycling the lever is halfway up. I have to constantly remind myself to push it down or find something to hold it in position.
Is there a way to fix it? Thanks!

jur

That lever operates an eccentric cam. The position of the cam is determined by 2 small set screws that tighten the lever to the cam axle. If the lever is pushed all the way down, the cam has to be just past its maximum point or it will simply undo itself. So loosen the 2 set screws and set the lever position further back so it will push the cam further. Make sure you get it right, it's a safety critical assembly.

I don't have any pics, sold my Birdy.

ehasbrouck

Thanks to all for the packing pointers. Looks like it will go as airline luggage, just requires a little more disassembly, not just folding.

Still searching for fenders/mudguards to fit a 2002 Birdy....

bhkyte

I have got a spare set. But as you know they are hard to get hold of. Not letting go of them!!
I got mine on ebay worldwide.

foldingdroid

Is it better to put Kojak tires on the rear and different wider tire on the front? Is this recommended or anyone doing this for their birdy bike or folding bike? Thanks.

yangmusa

In general, I don't think there's any benefit to running different tires on the front and rear. The exception being possibly offroad bikes. A friend lent me his cross bike, and that had a knobby tire on the front for better braking/turning control on loose surfaces, and a slick on the back for low rolling resistance. But for a folding bike - unless you have a very special use case I'd say not.

foldingdroid

Thanks a lot Yangmusa for the tip. I only managed to purchase 1 piece of Kojak here in Dubai, no stock everywhere else. I need to buy outside the country online.