Help!!!

I was riding around Vancouver this morning and on my way back to my hotel I lost a bolt from my derailleur, and with it, the guide pulley assembly. (parts 7 & 8 on the diagram)



I was able to get it to stay in a single gear so I could limp it back. Tried to jury-rig something with parts from Home Depot but that's just getting me the 2 top gears instead of 1 middle gear.

Is it possible to buy just the missing parts or will I have to get the whole derailleur? How do I find out which specific model of the Alivio I have? (I can't find the manual online right now.)

If I end up replacing the whole derailleur should I just replace the stock one or can anyone recommend a different one?

Guess I probably won't be bringing it on next week's business trip (San Diego).

Oh, here is where I was riding this week:

Tuesday (~24-mile loop from downtown around UBC, down near the airport and back through midtown):


Today (~20 mile ride from downtown, through Stanley park and across Lions Gate Bridge to North Vancouver and got in a little climbing in the foothills, sadly not enough time to get up into the mountains, although probably a good thing as it turned out):

Derailler bolts and pulleys should be easy to find at any real bike shop. Most older shops will have a box of used deraillers and will either canibalize one or sell you a used one. Normally the pulley width and bolts are pretty standard so it shouldn't matter who made the derailler.

Good luck, best to use blue loctite or equivalent on those pulley bolts since they will often bind the pulley if tightened really tight. Blue loctite is the type that lets a bolt be removed fairly easily.

Thanks Pine Cone, good to know!

I do have loctite at home, was thinking that earlier. That bolt had never been off before as far as I know. Must be all that jostling around in the suitcase.

Now several months in to riding my upgraded Birdy Touring and it's a real pleasure. Among the upgrades - XTR shifters and sram dualdrive 27 speed make it even more fun.

Plenty of life left in my Marathon Racers, but Kojaks might need to be tried soon.

I shall be taking it on its annual holiday to Dubai soon, and if it's very good, I'll let it play in Qatar as well.

I got a replacement pulley at the LBS today but they didn't have the right bolt. That's ok, I found one that worked at the hardware store.

Installed it tonight with loctite, I'm good to go.

Even though a Brompton with a small front hub nano motor is the best solution for me, I like Birdy much better in terms of design, especially with the expedition rack mounted. It's a pity front hub motors are not recommended on front hubs since I would have a front hubmotored Birdy with a Rohloff and High speed Schlumpf as a hitech commuter.

Dahon MU P8 or MU SL or similar models might be the reasonable way to go due to enormous price advantage over the others above, however they are completely unattractive, aesthetically bland and plain bikes with no wow factor to me and to many who thinks as I do. Some may think that loks are not important but then biking is not important for others, and this line of thinking has no end. If I would buy a Dahon, it would be just because my budget allowed only a Dahon.

Birdy Hybrid in Europe is around EUR 3350, and price increases with the addition of an expedition rack, hydrraulic brakes etc. Bionx fitted Birdies in USA seems to be around USD 2350 (2950 for PL350). And I am talking about Monocoque ones. Very huge price difference. Does any of you know what is the selling price of a Birdy Hybrid Monocoque in USA, original preconfigured by R&Me, not a Birdy with a Bionx added by a dealer.

Thank you

Many a speed TT pro, hyperglide owners would state that they own one of the best folding bikes in their niche. But yes not all Dahons are as competive.

I've been having fun taking it up the hill in Torrey Pines this week (even passed someone on a Cervelo yesterday)

https://www.bikely.com/maps/bike-path...-Pines-steeper

Couple of comments this morning:

From a roadie - "Sweeeeet bike!!!"

From someone standing in front of the hotel as I pulled in: "What the hell is that thing?"

I can see Incredi-babe getting tons of comments on that bright yellow Birdy ... in contrast, an elder, overweight man on his silver Birdy is practically invisible..

I went camping this weekend - by Birdy of course - and rode from Larkspur to Point Reyes coast camp. Small panniers on the front, handlebar bag, tent, sleeping mat and some misc on the rear rack. I got some odd looks and double-takes! Maybe because the front wheel is almost entirely obscured by the panniers??? On the way back, we rode through Point Reyes Station and stopped for lunch. The roadies were all over my friend's Bike Friday Pocket Rocket (& BOB trailer), but didn't spare a glance for the Birdy. Ah well, anonymity has its advantages too I suppose

...and I often get gales of laughter when pulling in at the station in the morning where there are lots of school kids thinking they're the coolest.

It's been said before: folders and recumbents are aren't for the shy and retiring

Does anybody know of a Birdy with an electric motor on the front hub?

I asked this to get some user review and also I will check rear hub motorized Birdies to decide against a Brompton Nano (front hub) but Birdy owners must be absent pedalling happily outdoors

Bringing back an old thread.

I recently moved from a Brompton to a Birdy and in researching others' experiences, came across this thread.

On the Brompton I did some touring and found the Brompton front-mount 'touring' pannier very good. I've made a simple adaptor that allows this pannier to be mounted on the Birdy. It attaches to the headstock area via two plastic hose-clamps. The pannier can be removed almost instantly (it unclips from the mount) and then is easily carried around. The bike still folds fine but is a little longer.



The pannier mounted. It looks a bit messy when empty but fills out nicely when full. Brompton recommend a max of 5kg and that seems about right. I also tried mounting the pannier on the handlebars and found, as have previous Birdy users, that it really negatively impacts on steering. Mounted as shown here the impact on steering is way less - almost negligible.



I also have chosen to fit a softer rear suspension bush. I have used a cut-down rear bump stop from the suspension of a Daewoo Matiz. It is more progresive than the original and allows more suspension movement on a given bump. I use cleated pedals and unless I am tired and am pedalling jerkily, rear suspension bounce is tiny.

Continuing from above, this pic better shows what the front Brompton panniers look like when full.

* no time now to ask million Q's * back later *

Studying your photos have given me some ideas how to attach my Xootr crossrack to my Birdy's head tube.

Just some questions on the rear suspension rubber bush: You mention it's more progressive. Now I know what that means but I fail to see how it is much different? Seems to me one rides with the bush under a certain compression and therefore a certain spring force; road movement would result in deviations around that operating point just as with a normal bush. The only difference I see is with a depression in the road which would cause the bush to more gently decompress and with longer movement... a sinusoidal movement would result in a lop-sided sinusoidal response... but the catch is the catch - it stops response beyond a certain point and so lops off the lop-sided sinusoid resulting in a little jar as the catch catches? (Sorry for all the double-talk.)

I suppose I may have to try something...

Are you sure? That seems like a very low limit for such a large bag. The touring bag is 31 liters. On this FAQ page, Brompton says the bike is designed for rider + 20 kg of luggage (presumably front + back).

Great idea though! I've always had "Brompton envy" for their clever luggage system

The bag modification looks great. I have both a Brompton and a Birdy and the ability to change bags seems to be very handy. I must admit mine are just for riding around town and not on long trips but they are both great bikes in their own way.

Jim

No I am not sure where I got that number from - I can't find anything official to suport that number. The two bolts that hold the mount to the Brompton frame are small (m5?) and the plastic coupling itself must be under a lot of strain at high weights. I may well be wrong, but ~5kg actually seems good on both Brompton and Birdy.

I didn't mention it but I upsized the bolts to M6 on my adaptor. I have also tested the Birdy+ Brompton bag with 10kg in it and it didn't break off, but I didn't like the bike's feel much.

Over the standard polyurethane:

1) for a given upwards acceleration of the wheel, the bush compression is greater, therefore the acceleration of the rider is reduced. In other words, the suspension has a greater effective travel under upwards bumps.

2) when the wheel meets a depression, it can travel further downwards without the catch catching, because the static deflection of the bush under the load of the rider is greater. In other words, in a static condition the suspension sits 'further through its travel' than it does with the poly bush. You can allow it to do this without running out of travel under bump because the rubber spring, with its convolutions, progressively hardens as it compresses.

With the ex-Daewoo rubber bush fitted, with about 50 psi in the tyres, and measuring from the rear carrier to the ground, about 70mm of rear suspension travel can be measured when the rider bounces up and down on the seat. With the red poly bush fitted, I measured 25mm movement under the same test conditions. So with the rubber bush fitted, the rear suspension has 2.8 times the effective travel!

I measured 25mm static suspension compression with the red poly bush and 40mm static compresison with the rubber bush. So at this ride height, natural frequency of the rear suspension with the poly bush is 4.1Hz and with the ruber bush, 2.5Hz.

Note that also I apply some preload, ie the unrestrained rubber bush is a little longer than the distance provided by the catch.

Anyone who thinks the standard poly bush is too soft will, I would think, intensely dislike the action of the rubber bush. But I am used to riding a self-built recumbent suspension trike with a lot of suspension travel and the Birdy immediately struck me as having rather ineffective rear suspension (but I think the front suspension is pretty good). The trade-off for the greater rear suspension effectiveness over bumps is that you need to pedal smoothly.

[Edit: looking at the above figures, you can see that with the rubber bush the static deflection is 40mm and the total travel 70mm, so the bike is sitting 57 per cent through its suspension travel. However, as the spring rate is non-linear, this is probably fine. Note also the measured 25mm static deflection AND 25mm total deflection measured with the red bush (anyone want to check these figures?) which indicates how incredibly steeply the spring rate of the red bush rises under compression.]

The rubber bush out of the bike:

I am riding the hard green bush and I'm 80kg. I am wanting to try out the rubber as I am a great fan of rubber - I have that in my Mini as well with enormous benefit over the original spring. I have often thought I should try rubber on the birdy but haven't yet. I have been using doorstops.

Are you in Australia? (Your Brommie pics are...) If so how did you source the bush?

Yes, Bungendore outside Canberra. However, I sourced the bushes when I livd in Queensland, at a Gold Coast wrecker (Pacific Motor Wreckers I think) that had heaps of Matiz cars. (I use the bump rubbers in other applications as well so I got a few. However, I just checked and I have only two left - and one will go in my wife's Birdy when we get it. The other I'll keep as a spare.)

The hydrolastic system was even better - I run a self-built variation of hydrolastic on my recumbent trike.

I am in the process of making a rear pannier support for the rear carrier. I wanted to use my existing Arkel RT40 and RT60 panniers, and still be able to use my Arkel Tailrider rear bag. I also wanted the panniers to be able to be easily removeable.

After trialling different pannier positions, I decided to mount them relatively high up. This achieved two things - it moved them forwards over the position they'd need to be if mounted low, and it also means that they will not rub on the moving mudguard stays (when a rear mudguard is fitted).

Before starting work on the final adaptor I did some testing with realistic loads in the panniers and found the balance and handling fine. I say that because I think many people's reaction will be that the bike will be unbalanced and hard to ride. It isn't - and in fact changing the weight in the front bag makes more of a difference to bike handling. That said, put too much weight in the rears and the seatpost mounting bolt (or anyway the palstic bushes) start to flex and the rear assembly can oscillate sideways. (The main mounting point for the carrier is the seatpost bolt.)



This pic shows the rear adaptor in place with two RT60 panniers, foam sleeping roll and tent. The Tailrider bag sits between the two panniers. The front bag is a Brompton (adaptor described earlier in the thread).



Rear view. I don't have in place the long tent and sleeping roll tubes that attach at the back of the RT60s, but there's plenty of room for them when I do attach them.



The adaptor. It sits over the rear tube of the rack. The panniers hang on the cross-arms and the lower hook fittings of the panniers go into the open vertical tubes. The link at the top stiffens the structure and also gives me a tie-on point for the tent and foam bed roll.



I looked at using a quick release clamp and/or wing nuts to hold the adptor on and then decided that simple cable ties would be lightest and easiest. A half-round tube brazed to the cross-bar locates the adaptor on the carrier.



The adaptor weighs 500g and will easily pack into a suitcase with the broken-down Birdy. Now I just need to finish brazing it, do some sanding and then give it some paint.

Final point - the new rear suspension bush (also described earlier in the thread) works well with the bigger load - for example, it doesn't bottom-out.