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Birdy thread

Old 06-23-22, 05:41 AM
  #1776  
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Originally Posted by jackyharuhiko
Thanks glye, CEBEP and jipe. I learnt so much about the Birdy in this thread.
I’m also the learning one here
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Old 06-23-22, 10:34 AM
  #1777  
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Originally Posted by jackyharuhiko
Talking about cassette, I also talked to the bike shop yesterday about the options. My Pacific Cycles Birdy 3 is factory equipped with Shimano Sora with 11-32T 9 speed cassette, and the shop recommended me to go to 11 speed cassette but with the lowest and highest gear teeth unchanged. I wonder what is the use of going with more speed without changing the max and min gear ratio? Smoother shifting? There is also a SRAM electronic wireless system but that’s not essential to me.

I don’t know how is the original hubs, I know that the front hub has to be custom made and it’s Birdy-branded, but the back hub is a low end Shimano M475L which I saw some poor reviews online, it also stops quickly in a free spin. Anyway it’s not an issue for me since I changed the wheel set already. This hub has ceramic bearings, and it free spins for a long time, but the improvement to the ride quality is not as strong as changing the tyres and the BB/crankset. But it certainly looks good and the carbon wheels shed about 400g from the weight. Now the whole bike weighs about 11.1kg.



which cassette did you end up using?
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Old 06-23-22, 11:10 AM
  #1778  
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Originally Posted by CEBEP
which cassette did you end up using?
Shimano 12 speed Ultegra CS-R8100 11-30T cassette, used with the SRAM Rival eTap electronic wireless shifter


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Old 06-23-22, 11:25 AM
  #1779  
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Originally Posted by jackyharuhiko
Shimano 12 speed Ultegra CS-R8100 11-30T cassette, used with the SRAM Rival eTap electronic wireless shifter


Thanks. Is 11t long enough for you?
I assume you have 52t chainring?
Also which rear hub dis you end up installing?

eTap looks sexy, pity not available for 10s.

Last edited by CEBEP; 06-23-22 at 02:48 PM.
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Old 06-23-22, 02:24 PM
  #1780  
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In theory, its not possible to use a Shimano 12s cassette because the cog spacing isn't the same. It only work because the difference is very small.

For increasing the chainring size, the limitation is the chain tensionner around the chainring that hold the chain while the Birdy is folded. I think the maximum chainring size is about 56t.


For the hubs with XD and XDR freewheel (for 11s, XDR is not needed, XD is OK) is 135mm with quick release, I know the Hope RAS4 and Tune Climbhill. The Hope is cheaper than the Tune and a little heavier (but weight much less than the Sunrace). But there are also from some other brands Bitex, Extralight, Hubsmith, look on the Ginkgo (my wheels were made by Ginkgo, they are specialized in special wheels, small diameter, wheels for trike and velomobile...)
The fact that they aren't on big webshop in 135mm QR5 is due to because the demand for this spacing is low, most new bikes have 142mm/12mm several of these hubs have exchangeable axle and are convertible is several spacing and axle diameter, my Tune hub was delivered wrong type by Tune = 142/12mm thru axle and Tune send me a conversion kit to 135mm QR5, the conversion can be done without any tool. Same for the freewheel body, its convertible. For instance the Hubsmith wheelset of the Pacific Cycle Birdy R20 11SP can be converted to XD/XDR.

If I was you Cebep, I would use the Birdy with its original Sunrace cassette and see what happen as I did with mine during about one year. Besides the issue of Glye, the transmission works very well with smooth gear changing, the gear inch range is excellent, the only complain I have is that I have the impression that the cassette wear faster than a more high-end cassette.

For the Shimano Ice Freeza discs, they wear faster than the steel discs and make much more noise when braking hard, I do not like them much, I switched to it only because I needed a centerlock disc and didn't want to use a conversion 6 holes to centerlock.

Last edited by Jipe; 06-23-22 at 02:41 PM.
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Old 06-23-22, 07:08 PM
  #1781  
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Originally Posted by CEBEP
Thanks. Is 11t long enough for you?
I assume you have 52t chainring?
Also which rear hub dis you end up installing?

eTap looks sexy, pity not available for 10s.
it’s okay with the 52:11 gear ratio but of course I wish it could be faster with smaller smallest gear at the back. But I would have to change the freewheel so the Shimano set is a good choice. Shifting is smooth and fast with the SRAM wireless derailleur.

I changed the whole wheel set to ImperiumCycle’s 18” 355 carbon fibre wheelset. The hub’s specifications is: AL-7075/Straight Pull. Front: 100mm, Rear: 135mm with Enduro Bearings.

Last edited by jackyharuhiko; 06-23-22 at 07:23 PM.
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Old 06-24-22, 03:29 AM
  #1782  
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Imperium Cycles is probably using a hub from another brand to build their wheels, is there a brand on the hub itself ?

Often, the freewheel body is removable and exists in several standards, its for instance the case for Hubsmith, Hope, Tune, DTswiss...

You could maybe find an XD or XDR freewheel body for your Imperium Cycle rear wheel.
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Old 06-24-22, 05:07 AM
  #1783  
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I wonder if anyone considered upgrading seat post to titanium one? If it makes any sense to save weight. Also for whatever reasons I see two seat post Ti models for Birdy 33.9mm and 34.9mm. Both 600mm in length. If Birdy’s seat post is aluminum I believe there wouldn’t be too much weight difference
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Old 06-24-22, 05:14 AM
  #1784  
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Originally Posted by CEBEP
I wonder if anyone considered upgrading seat post to titanium one? If it makes any sense to save weight. Also for whatever reasons I see two seat post Ti models for Birdy 33.9mm and 34.9mm. Both 600mm in length. If Birdy’s seat post is aluminum I believe there wouldn’t be too much weight difference
I saw some people changing to carbon fibre seat posts but it will need a double clamp to hold it in place. Not sure about titanium ones
My Birdy weighs about 11kg now so if I want more weight savings I will need to pay a lot for carbon parts … or try to lose a few kgs on my own body, which is the cheapest. Haha.
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Old 06-24-22, 08:07 AM
  #1785  
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Guys, could you reconfirm if it’s the latest R&M frame? I assume Mk3?









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Old 06-24-22, 09:03 AM
  #1786  
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Originally Posted by CEBEP
Guys, could you reconfirm if it’s the latest R&M frame? I assume Mk3?

It's at least an mk3, and as far as I know mk3 is still the newest model. Mk3 has disk brakes, all mk2 pictures I see have rim brakes. I don't know if that was always the case. But note for instance the edge along the top outside of the rear swingarm. Mk2 doesn't have that, see https://en.wikipedia.org/wiki/Birdy_...ller_Birdy.jpg
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Old 06-24-22, 09:12 AM
  #1787  
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Thanks glye
If you haooen to use rear panniers on your rear rack would you suggest where did you secure it’s bottom part to, the fender support rod?
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Old 06-24-22, 09:13 AM
  #1788  
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Note that in your picture, the seat clamp is facing backwards, as it is on most bikes. On some of the official R&M Birdy photos it is facing forwards. That's a simple trick if you want to reduce the seat-handlebar distance with a few cm, as I did. I have the more forward leaning stem, unlike the backward leaning one on this blue bike. I'm not sure, but it seems to me that black bike also has the backward leaning stem...?


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Old 06-24-22, 09:33 AM
  #1789  
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Originally Posted by CEBEP
Thanks glye
If you haooen to use rear panniers on your rear rack would you suggest where did you secure it’s bottom part to, the fender support rod?
I don't use rear panniers. I guess it might be possible to secure them with velcro to the fender support, but given the suspension movement you would quickly wear the paint off the support. You could wrap the support in black duct tape to avoid that.

Here's my Birdy with the biggest touring load I use: Front handlebar bag (klickfix), small front lowrider panniers, and rear rack top bag (klickfix). This bag has side pockets that can fold outwards and down to give more volume, as they are in this picture. They are so short that they don't need support.

In this setup the front panniers will wear the paint off the front side supports due to front suspension movement. To avoid that I put headshrink tubing on them. Duct tape should also work. Personally I don't worry about the look of scraped off paint on racks, but it can go so far that it becomes a structural problem. I have a big bike where the rack supports are no longer round, but have flat sides worn into them from years of pannier rubbing. And that's not even a suspension frame. Eventually that will cause failure, if not stopped.


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Old 06-24-22, 09:57 AM
  #1790  
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By the way, since we discussed 9t cassettes: There is also Campagnolo Ekar: https://www.campagnolo.com/US/en/Mec...s/ekar/gravel2

They have 13-speed 9-36t cassettes among others. That's a good gearing range for the Birdy, assuming you can find a dealer, a 135 mm QR disk hub for their N3W cassette standard, that you accept using drop bars (makes the folded bike bigger), and have a good chunk of extra money. It's something like € 750 for the Ekar parts you need, plus hub and drop bars. Many caveats
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Old 06-24-22, 10:29 AM
  #1791  
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Originally Posted by glye
Note that in your picture, the seat clamp is facing backwards, as it is on most bikes. On some of the official R&M Birdy photos it is facing forwards. That's a simple trick if you want to reduce the seat-handlebar distance with a few cm, as I did. I have the more forward leaning stem, unlike the backward leaning one on this blue bike. I'm not sure, but it seems to me that black bike also has the backward leaning stem...?


Yes, mine is backwards leaning stem, 10 degrees comfort stem as Birdy calls it. Thanks for the tip.
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Old 06-24-22, 11:02 AM
  #1792  
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Originally Posted by glye
It's at least an mk3, and as far as I know mk3 is still the newest model. Mk3 has disk brakes, all mk2 pictures I see have rim brakes. I don't know if that was always the case. But note for instance the edge along the top outside of the rear swingarm. Mk2 doesn't have that, see https://en.wikipedia.org/wiki/Birdy_...ller_Birdy.jpg
there are disc brake version of the Birdy 2, at least for the Pacific Cycles version.
A good indicator of Birdy 3 is the rear swing arm.


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Old 06-24-22, 11:09 AM
  #1793  
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I heard swingarm on early models was breaking in half for some users. As far as I know this flaw is now fixed.
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Old 06-24-22, 12:04 PM
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Yes, the swingarm is stronger now. But check the manual when you get it. There are some unusual recommendations there, like that you should replace the stem and front swingarm after X kilometers and/or years of use. I don't remember exactly. It was a large number, but still. If you ever have a hard crash with it, it's good to check extra carefully for cracks.
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Old 06-24-22, 12:07 PM
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Originally Posted by glye
Yes, the swingarm is stronger now. But check the manual when you get it. There are some unusual recommendations there, like that you should replace the stem and front swingarm after X kilometers and/or years of use. I don't remember exactly. It was a large number, but still. If you ever have a hard crash with it, it's good to check extra carefully for cracks.
I think it’s 3 years. Dis you change it?
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Old 06-24-22, 12:17 PM
  #1796  
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Originally Posted by CEBEP
I think it’s 3 years. Dis you change it?
Found it: https://www.r-m.de/media/filer_publi...te_10-2015.pdf

At least the 2015 edition. It says to replace the front swingarm "at least every 20 000 km".
And replace the stem and steerer (edit: and the handlebar) "after a crash or 10 000 km or 3 years". I'm past the 3 years limit, but haven't changed anything yet.

Last edited by glye; 06-24-22 at 12:24 PM.
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Old 06-24-22, 12:20 PM
  #1797  
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Originally Posted by glye
I'm past the 3 years limit, but haven't changed anything yet.
Exactly. I bet nobody did
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Old 06-24-22, 01:43 PM
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Just checked Birdy models in Asia, all cassettes start with 11t smallest cog. It’s all subjective of course, and every rider will have it’s preferences, but it’s hard to imagine that if 11t smallest cog would be terribly high they wouldn’t try offering anything lower.

Last edited by CEBEP; 06-25-22 at 12:33 AM.
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Old 06-24-22, 06:13 PM
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Originally Posted by CEBEP
Just checked Birdy models in Asia, all cassettes start with 11t. It’s all subjective of course, and every rider will have it’s preferences, but it’s hard to imagine that if 11 would be terribly high they wouldn’t try offering anything lower.
Yes mine came with Shimano Sora 9 Speed with HG400 11-32T cassette. I didn’t really like it.
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Old 06-24-22, 06:17 PM
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Originally Posted by CEBEP
Exactly. I bet nobody did
the headset of mine started to make a weak squeaking noise when I turn the handlebar a little. The bike shop said it’s normal, the headset is of poor quality and I’ll come to them to replace it within a few months.

(Note: I didn’t buy the bike at their shop so it was not them who deliberately made it bad)
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