On kludging with clutches
- Published on Thursday, 23 February 2012 18:00
- Written by Joachim van de Haterd
I do my own stunts. That goes for both my driving and the way I keep my bike in a ridable shape. Recently though, I was almost forced to have a professional dismantle a large part of my bike. The reason? Bad clutch design.
Shortly after my last service, I noticed that whatever I did, my clutch cable was too tight. On the handlebar, I was not able to loosen it. Since I have already had the pleasure of having to replace an entire clutch, I knew that I would have to stop riding and find a solution.
Roughly speaking, there were two options: either my clutch cable had to be adjusted on the clutch side, or the cable had to be replaced. I checked my cable for unwanted friction. It appeared OK, so option 1 it was.
At this point, please allow me to state that I am a weekend mechanic. For me, it is a hobby, and since it is neither my vocation nor my biggest talent, I have a decent set of tools. However, the most specialized tool I have, is a torque wrench. There is probable a proper tool for this job. I do not have it though.
That being said, I have a good head on my shoulders, and I was to be as careful as possible. After removing the fairing, I noticed that the clutch cable was too tight indeed. For the uninitiated and non-technical folks out there, please allow me to explain the system.
The adjustment bolt is held fast by a locknut. So, the intrepid mechanic (that would be me), is to loosen the locknut, adjust the cable until the clutch meets the factory specification, and retighten the locknut again. Simple, no?
Hardly so. The locknut is in a tight space between the gearbox and the final drive. While holding the adjustment bolt with a #11, you fasten the locknut with a #13 spanner. However, that won't work, because there simply is no space. A normal-sized spanner is too long and unwieldy. Furthermore, since you need to sit on the left side of the bike, you have to do everything with your off hand if you are rigth-handed like 90% of all people.
Apparently, the clutch mechanism is built with left-handed snakemen in mind.
How to (almost) lose both a tool and a gearbox
Although I am not a particularly talented mechanic, my powers of improvisation are huge. I am a programmer after all. I found an old spanner that was a lot shorter and thinner. My grandfather would have called it pisbakkenstaal or urinal steel. However, I was able to get a grip on an otherwise unreachable bolt.
Picture me lying on a cold garage floor while bending my arms and wrists in an unnatural way to tighten a nut that is not physically reachable with standard issue tools. A slight fumble was needed before my spanner disappeared in the big cavernous hole behind the clutch cable, into the deep innards of my bike.
At that moment, I felt my heart sink. I was well and truly forked. Sideways. With a chainsaw.
Kludging to the rescue
First, I tried to pry the little spanner free with my fingers. Needless to say, the spanner had fallen too far into the guts of my bike. Useless. Fortunately, I found a nice gadget somewhere in my garage. It is a flexible piece of wire with a strong magnet and a little three pronged retractable claw thingy on one end. I decided to use that, and since the wire thingy is very slim with its 4mm diameter, I was able to at least touch the spanner. The magnet was not able to reach it. Furthermore, the spanner fell even deeper.
That would have been a disaster, were it not that it had fallen into a space that was reachable from underneath. I took my trusty thingumabob and used the claw to retrieve that pesky spanner. Problem solved. Kludging to the rescue. Angus MacGyver would have been proud!
Dear BMW designers
Next time you design something that should be easy to adjust, please keep two things in mind:
- Keep it reachable.
- Make sure that it is not near any big hollow hard to reach spaces
a weekend mechanic