2cycle2

Happy New Year everyone. Don't know if you've noticed but r-m seem to have 3 new models in their 2012 catalogue. One is a drop bar version with disc brakes called the 'Race Disk'. This has a double chain ring and hence wider gear range looking similar to the 10Y Birdy. The other two 'World Birdy - sport & comfort' have a new frame reminiscent of the classic shape but with internal cable routing and a non circular section straight top tube. Does anyone have any info/opinion about this new frame? Lighter or heavier - stiffer or weaker? I'll try to paste a picture again . .

Clownbike

Funny, none of these are on the R&M site, that I can see. Guess you folks on the other side of the pond see the site different. Seems R&M has a way to filter content based on browser or something.

Just checked my '06ish Silver and the top tube has an oval cross section, so the two new bikes seem to use the 'classic' frame and are nothing new except for the cable routing. Aside from the color(colour) and the crankset, the World Sport is a dead ringer for the Silver. The monocoque frame design was develped to lighten it a bit and inrease stiffness, both already admirable characteristics in the original.

I'm hoping to see some closeups of the disc model, as it appears the calipers are mounted directly to the frame without braze ons. Could just be the photo though.

2cycle2

They appear on the German version of the r-m site (sprechen sie deutsch?) see:
https://www.r-m.de/faltraeder/modellu...c/alu-poliert/ for example.

The new cross section looks more triangular than oval. I'll try to paste a better picture but this forum seems to cut down the size of my pics and they don't appear in the text like others. I'm obviously missing something . .



You should be able to see more on the above link (use magnify) but my comment above applies. Is there some way I can set this to notify me when someone adds to a thread or do you just have to keep looking?

Clownbike

Thanks for that. Too bad we can't get much of this stuff in the states. Seems that there is little in the way of distribution in the whole western hemisphere.

From the looks of the photo, I think it's the lighting and heavily photoshopped image that gives the impression of a triangular tube, hopefully better pics will start making the rounds. It seems the front suspension link has been modified for the disc caliper, so maybe they've made other changes as well.

I get periodic emails that there has been activity on the forum, but don't remember setting anything up for that. Just seemed to start happening. Maybe something in your Profile.

2cycle2

Thank you 2.

If you compare the interface between the top tube and seat tube /down tube you can see the difference between the World frame X-section and the Classic:



From the r-m website (Spezifikationen) did you note that the Race Disk brakes are the same as those on the Titanium model - ie Avid BB7 mechanicals (not hydro) - there is probably a reason for that. Even these carry a 300g penalty relative to V brakes.

energyandair

The seat post clamp arrangement is also different from those in the 2 original frame versions I am familiar with. Its more like that in the monocoque frame.

Clownbike

Thanks for the new pics. While maintaining the basic design, it does look like they've changed the top tube as well as the seatpost clamp. Seems odd they would continue refining the older design in parallel with the monocoque. Sort of splits the R&D and fabbing costs between the two, driving up the unit cost for both.

Yes, did notice the BB7s. As they are higher end mechanicals, could be that R&M would have wanted to use upper end hydros, which would probably have driven up the cost. Could also be that hydros just don't work well with this type of fold.

Transformer

I wonder if they decided--after building the jig for the limited edition titanium model--to continue to use it to crank out some aluminum frames.

2cycle2

I had heard rumour of the Titanium model several years ago. It was said to be much more expensive than a conventional Al frame and turned out to be no lighter (the 2011 Titanium model is listed at 11kg despite high end components) - so the original project was shelved. Perhaps they were wondering how to shift a few hundred spare prototype Ti frames. . ?

It is noticeable that the Birdy has put on quite a bit of weight over the years (unlike the Brompton which got lighter). I have reference to the first Birdy Blacks from 1997 weighing in at 8.7kg (~19 lbs). But there were weak points, like the seat clamp, and complaints of creaks, squeaks and fatigue cracks. Does anyone have a list of important changes? I know the front swing arms were changed before the seat clamp and expedition rack mount points were added. Presumably these and other monocoque frame improvements will be captured in the new World one too.

The classic frame shape has remained surprisingly popular, as evidenced by prices those older bikes still fetch on Ebay. The new World frame may just be a way to capitalize on that - and perhaps benefit from higher build volumes - they only offer one colour for each model and few accessories but claim they will be sold world wide. Could be cheaper to make than the mono too – less welding. Perhaps they plan it as a market probe before switching higher spec’d models to the new frame? It will be interesting to learn more once the new bike is properly launched.

However, to my mind the question remains: Why bother changing from the Classic round top tube to a more boxy triangular one? Is it cost, function or a Germanic perception of aesthetics?

2cycle2

Sorry if answering your own question is a protocol violation but I found the following thanks to Google and thought others here might be interested: https://translate.google.com/translat...26prmd%3Dimvns

This looks like a useful list. Note for example 2012: ‘The World Birdy models are produced consistently for the whole world, to save costs. The equipment and the color are given, there are limited options available from the factory. The frame is similar to the classical framework. Auffällgster difference: The main tube is rectangular.’
And in 2010: ‘A Birdy without disc brakes can not be easily retrofitted, because the disc brake models have special wings, which does not exist as a single part.’

Never-the-less, assuming the new frame is at least as good as the existing monocoque (?) it still seems to be a good idea to follow jur’s advice proposed earlier on this thread – buy the basic model and upgrade components to suit individual needs. Note that there is a 2.5 X price difference between the World Sport and a Speed or Race Disc – and > 3 X for a Rohloff model (could find several good retrofit components for £2K even in the UK). I am strongly tempted.

Folding-Bikes

Found some pics that belong here

First Birdy





Juan

tablet

Cool pics! Thanks!

bhkyte

Some issues with this if anyone can advise ?
1) the chain seem too short, as it locks in low gear (due to excess chain tension?0
2) seems to be some lateral play in rear pivot, adjust this out??
3) chain guard catchs on rear frame when folding unless done very slowly it bounce off it. Bottom bracket alignment? or remove doulbe chain ring guard ?
4) chain comes of when folding at front chain wheel despite double guard.
5) bit of play in front stem that cant seem to get rid of by tightening bolt, ie it does not tighten any more, and tryed putting washers behind it to space out.

General question do birdies with IHG and chain tensoner fold better than birdie with dyraillers? If so I might get a IHG wheel built up for it

BruceMetras

Looks like you're missing the little device to take up chain slack when folding.. there are aftermarket chain slack removers for that purpose also .. they don't touch the chain normally, just come into use when folding.. so yes, you're chain is too short if it's binding .. and without something to remove the slack, the chain will come off of the chain ring.. Pacific has a new tensioner on their site.

.be
Stock device looks like this:

bhkyte

Thanks Bruce,
I have a shop near me that sells birdies so should be able to order part. I am also trying to finish my bullbar Brompton off.
is that your dualdrive birdie?
Thinking of doing this and adding bullbars, and brifters; my usual preferred mod on folders ( I have a dahon androes stem for the job.)

I think play problem (2) could worn bushes ?? that should be straight forward.
Problem 5, Do i need to order a new stem or part due to wear? play is only slight, but in my experience is that birdie stems are play free ??

darukhan

LitePro also makes an aftermarket Birdy chain tensioner in various anodized colors...

darukhan

I also have a little bit of play in my Birdy stem hinge. (I'm the second owner of an older model Birdy.) I have not tried to adjust my hinge yet, but if you look in the manual, there are instructions on how to properly adjust the stem hinge.

Here is a link to the PDF manual online: https://www.birdybike.com/BirdyOwnersManualv2.pdf

Notice in the manual, it states that you should not need to over-tighten the hinge bolt. When I get a chance to play around with adjusting my stem hinge, I'll be sure to take pics and post my experiences/results.

energyandair

We have 2 older style Classic Birdies and one Monocoque.
I see the following differences between our Classics and the World frames.
Front suspension pivot change (like monocoque) simplifies mounting of mudguards (fenders)
More tire clearance at top of front swing arm (The older classics have a mounting point for caliper (road bike) brakes which reduced tire clearance)
Newer headpost clamp (looks like monocoque one)
Cable routing runs through top tube (like monocoque) which is a bit tidier
Top tube changed from oval to modified triangular. May reduce folded size a bit? May reduce frame resonance?
Seatpost clamp style improved. Worthwhile but may increase folded size a fraction
New style seatpost (like Monocoque) provides more front back adjustment
Has mounting points for rear and front racks (like Monocoque)
I'm not sure if the seatpost angle is the same as the Classic, more upright like the Monocoque, or something different

Anyone got anything to add?

bhkyte

Hi thanks for help. Most issues sorted. Loosed rear frame alley key bolts squeeded with sash clamp and retightened seems to have got rid of rear frame play.
Changed rear inner tube as this caused tyre tyre to buckle not sure why. Will look in manual for stem adjustment. I ll order chain tensioner soon.
Need to follow manual toI get it to stand when folded

tcs

They're not really quite the same thing, but the Birdy World and Dahon Jetstream now seem to be the same retail price in North America.

bhkyte

Think I am right in saying that In Uk currently the cheapest Biirdie is £40 cheaper than a 3 speed brommie. Seems a tad mad to me if you compaire components.

jur

The retail price seldom reflects real concepts. Instead it reflects what the market dictates. So a Birdy isn't cheaper than a Brommie, rather people are willing to pay more for a Brommie.

bhkyte

Where can I order a chain tensioner for a drialler model mentioned earlier?
Tried local dealer and told not sold seperatly.
Where can I order the litepro mentioned ealier? I see cycpiedia on internet as a potential source.

2cycle2

I used Cyclopedia (thecyclopedia.com) based in Singapore to buy a LitePro front D adaptor for my Birdy. That seemed to work pretty well. I would be interested to hear if you get their chain tensioner - I converted my 'World Sport' to a use a double chain ring with an Ultegra short cage dérailleur which gives good ground clearance but isn't compatible with a conventional chain tensioner (too much chain interference at one end of the range or sprocket interference at the other). I would be interested to hear if you or others have a solution . .

bhkyte

Really been enjoying using the birdie recently. Good to go for a ride for the head!
Mainly been down river side in york , but recently went on proper mountain biking course on it in Dolby forest. It coped well ,but when I got back I realised I had lost a circlip in the stem that could have mad thew stem come apart. I will refit these.
Wounder what other birdie users think about mbt on a birdie. I know thw manufaters do not recomemd it. Am I bound to break it!