Birdy Bicycle Information

Curing rattles and other noises

The stiffness of the Birdy frame, combined with the supple suspension, inspires confidence, and gives an excellent ride. Unfortunately, as is often the case with aluminium frames, it seems, at least on my bike, to be rather prone to a variety of rattles and squeaks, although none of these seem to be any cause for serious concern. Such noises are very irritating, and as yet I haven't traced or cured them all yet. If you have any other tips on tracing and fixing noises, please let us know.

Here though is a list of sources of some noises that I have found, with comments on how I've reduced or eliminated them. I'm not suggesting anyone else should copy my actions - it's up to you what you do with your bike, and you should never attempt any adjustment or modification unless you are competent to judge that the action is safe, and you have the skills, experience, equipment, materials and judgement to do the work. If in any doubt, always have work done by a competent cycle mechanic.

When trying to track down rattles I find it convenient to carry a lump of BLU-TACK, which can easily be applied and removed to suspected sources of rattles to see if it stops them. Obviously I don't put it anywhere where it could jam any essential moving parts! Cable ties and rubber bands (sometimes cut and then tied around a suspect item) are also useful, again subject to the proviso that they musn't be put anywhere where they can get caught in moving parts, or where they will restrict necessary movement of parts.

One of the worst sources of noise I have traced so far is the Birdy pump mounted in the seat pillar. It is inclined to rattle, with the spring moving about over bumps. Although the mounting in the seat tube is convenient in that the pump is concealed from possible theft, and there are no specific alternative mounting points, it is worth considering an alternative, particularly as this type of pump with a flexible tube to the tyre vale is not very effective. I now use a Blackburn mini pump instead, mounted on the top of the main frame top tube. I use one of the alternative Blackburn mounts which is available for the pump, and which attaches to the frame with a self adhesive foam pad and cable ties. When fitting a pump of this type bear in mind:
1. Mount it where it won't interfere with folding.
2. Mount it where it won't interfere with pedal movement or the heels.
3. Mount it where it won't get damaged when carrying the bike (underneath the main frame top tube is therefore NOT a good idea).

The metal retaining clip on the brake cable which locates it by the left front suspension bearing can rattle. Some padding can eliminate this. I'm currently still using some BLU-TACK - crude, but effective.

On my bike squeaks developed very soon in the front suspension bearings, and hence a little lubricant was applied. The photograph was taken soon after applying a little of a molybdenum based lubricant, and before cleaning away the surplus - so you can see traces of it around the bearing.

Another possible source of squeaks is any movement in the joint for folding down the steering stem. I was not convinced that in fact this was causing any squeaks on my bike, but I decided to treat it just in case. Apart from making sure that the joint fixing is properly adjusted (see the instructions with the bike) it may be a good idea to lightly grease the surfaces - the photograph shows the joint immediately after lightly greasing it, but before the surplus grease was removed. I again used a molybdenum grease, as this was to hand.

Here is the biggest problem of all on my Birdy Red - the Dia Compe V brakes on the front of the bike. The noodle which leads the cable to the brake rattles on the caliper lever - here you can see electrical cable wrap being used round the noodle to help matters. It doesn't solve the problem completely, and at present I've also put a small piece of BLU-TACK at the point of contact to give additional padding. It also seems that the two plates you can see to the left and right of the lever and noodle rattle. Any action to reduce the rattling must not stop free movement of the braking system. I confirmed that this is a source of noise by tying a cut rubber band once around the link, cutting off the end and making sure that it would not interfere with braking, and that it couldn't get jammed anywhere important, even if it broke. With the band fitted there did seem to be an improvement, but an engineering solution has yet to be developed.

The front suspension securing catch on my bike did not firmly locate the spring against its mounting, so that on the rebound it was possible that the spring would move away from the mounting, and rattle when it next makes contact. The catch, boss on the frame, and top part of the spring are shown in the photograph. Releasing the catch and pivoting the wheel down, as in the folding action, showed that there are 2 adjustments possible. The first is on the circular top mounting boss. The bolt locating this is not in the centre of the boss, so by rotating the boss you can alter the alignment of boss and spring, which at the same time alters the movement of the fixing catch. The alignment was fine on my bike, so no adjustment was needed. The second adjustment involves rotating the spring about its mounting on the forks. This alters the amount of space between the catch and where it clips onto the spring - if it is rotated too far one way, then the spring can move about as was happening with my bike, while if it is too far the other way, the catch cannot engage the spring. To rotate the spring it was first necessary to loosen the bolt which hold it to the fork assembly, which was done using a 5mm allen key inserted down through the centre of the spring and the inner rubber. Once the spring had been rotated so that the catch holds it firmly against the boss on the frame, but fully engages, the bolt was retightened.

Some noise can come from the cables beneath the main frame tube knocking against this tube - the large aluminium tube acts as a sounding box. The locating rings have to be a loose fit, since the cables need to move during folding. I've improved matters by fitting a red electrical cable tie round them, but it has to be left quite loose to prevent it interfering with cable movement during folding.

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