Jul 092012
 

I made a huge leap in reducing the noise pollution from my mountain bike a few months ago; I replaced my Hope Pro 2 rear hub with an XTR hub.

Whilst riding, and also in my GoPro HD Hero 2 recordings, I was hearing a lot of clickety-clackety noises when going over very rough ground at speed; I put this down to chain slap. So I added a Bionicon C.Guide V.02 chainguide to my triple-ring setup in the hopes of reducing chain slap. The Bionicon C.Guide is a modern take on the DCD (Dave’s Chain Device) that was so popular in the 1990s.

Bionicon C-Guide V.02 chainguide

Before fitting the Bionicon C.Guide I feared that the chain trundling through the plastic guide might cause some additional noise; this fear was unfounded as the device, so far, is silky smooth (the Squirt lube also seems to help). This, combined with the rear hub change, resulted in a very quiet bike when out riding.

However, there were still some mechanical noises in my GoPro camera recordings. I soon pinpointed this to the camera itself and eliminated that noise by opening it up and putting in some foam padding. But mechanical noise in the recording still hadn’t been completely eliminated. I traced these remaining noises to two items that were close to the GoPro camera: the Satmap Active 10 GPS device and the Knog NERD 12 bicycle computer.

On the Satmap Active 10, it was just the rechargeable battery bouncing around in the compartment. I soon resolved that by putting some foam padding in there.

On the Knog NERD 12, the noise appeared to be coming from within the device when I shook it. I took drastic action by cutting open the NERD with a junior hacksaw; this was done by cutting around the sides of the display. I soon had the unit opened. There were a bunch of items in there that could cause noise if shaken so I put some blu-tack padding in strategic locations within the device. I reassembled everything but have, temporarily, used some blu-tack for moisture protection and cello tape (or scotch tape in the USA) to hold the unit together; I’ll be using some epoxy resin to provide a more permanent assembly of the NERD at some point. Anyway, noise gone!

I do have a traditional mechanical bicycle bell that makes a little bit of noise when shaken and I have found no way of eliminating that noise. I could replace the bell but it was a birthday present from my friend’s 4-year old son so I’m unlikely to replace it any time soon! The noise is only slight and not really noticeable in the GoPro recordings so I can live with that.

The only other potential source of noise is that caused by the brake cables and gear cables hitting the GoPro camera housing whilst riding over bumps. Now, that does need some fixing. I’m looking at better placement of the GoPro and somehow fastening the cables so that they don’t hit the camera housing. I’ve not yet found a solution but have some ideas that I need to try out. It’s going to be trial and error I’m afraid.

Funnily enough, my rear disc brakes have just started to squeal a little. Oh dear, when will the noise stop!

Article by Kulvinder Singh Matharu – 2012