16 Aug 2014

16th August 2014 The battle of Athena Pt.2

Saturday 16th 60F, 16C, quite bright at intervals but very cloudy with a breeze. The forecast is for dry weather until later this afternoon. It ought to be a good day for a ride. Until I want to come back again. The westerly wind is supposed to gust to 25mph. Nothing unusual in that until I want to get anywhere other than merely local.

With the Trykit deprived of its usual ballast I rode to Odense. Big mistake. Nobody in Odense stocks Campagnolo. One bike shop manager told me that "nobody uses Campag." To which I quipped: Nobody except Nibali! To which he smiled.

Having visited the majority of decent cycle shops in Odense I had to run the gauntlet of a fierce headwind all the way home. At least the broken glass on the cycle paths did not cause any damage. I ran over three lots but at least no sociopathic cyclists or scooterists tried to take me off this time. As several nearly managed on my last visit.

Look what I found at the end of the rainbow! This pretty front changer clamp by BBB is not merely a duplicate for the butt ugly Shimano offering. I shall file and smooth the fixing groove to rotate the Athena into a more useful angle of attack to the chainwheels. The steep seat tube angle [76 degrees] on the Trykit makes front changers sit much too upright. So the cage is not concentric with the chainwheels. Which is bound to affect the cage ramps, gear change and chain clearances on the different chainrings.

Front changers and their clamps have no means of angular adjustment. Which just goes to prove how little the manufacturers really care about accuracy! Or is there some unwritten standard seat tube angle to which every frame manufacturer adheres when placing their orders with the Chinese sweat shops? Thought not. To quote a former acquaintance while he repeatedly cut professional corners: "It'll be alright." Alright is never good enough in my book! Not when it makes a complete mockery of the bling manufacturers endless bullshit propaganda about accuracy to justify their rip-off prices.

The Athena front changer is proving excellent. Swift and faultless changes on the two inner chainrings in all gears. I didn't need the biggest chainring today. My plans to modify the changer clamp should solve the large chainwheel problem with a following wind. Probably the only time I will really need it in the absence of Danish mountain passes!

Finally, after 40 years of waiting, I have added some decent 13/14 mm cone spanners to my vast, assorted collection of tools. My '105 front hub needs both sizes. I could not bring myself to attack the cones with anything less than the real thing. For some reason cone spanners are very poorly available in the bike shops I visit. Several times I was almost tempted to grind down some normal, chrome vanadium  spanners but always resisted the temptation. Once the surface plating has gone they quickly become very ugly indeed.

The Continental 4000S tyres definitely feel slower than the Duranos. Quite hard work in fact. They must be at least 2mph slower than the Duranos at the same pressures [90psi] and pedal effort. Probably Continental cheating on the TPI again. Perhaps they will ride up with wear, Sir? Whatever. 46 miles.

Sunday 17th 58F, 15C, overcast, windy, wet. Rain or thundery showers forecast for all day and tomorrow. I'd better get on with modifying the front changer clamp. The first attempt was too laid back. The rear of the cage was now closer to the big chainwheel than the front. The opposite of its starting point.

I have set up the changer clamp in a small, plastic-jawed vice to protect the paint and ensure a firm grip. On the other side of the workbench I have clamped a piece of 2x4" as a fixed height rest. I am wrapping a single layer of emery paper tightly around a meter length of 9mm pipe to gently wear away the curve. Because the wooden rest is fixed in height and the clamp is fixed in its angle the emery paper cuts flat and straight. Trying to do it freehand would only produce a convex curve at the top and bottom of the clamping surface. I also have the G-cramps guiding the pipe so it cannot veer to left or right. This will ensure that the new curve I put on on the clamp surface does not turn into a trumpet shape. The main problem is how small a change in the clamping angle is required.

A picture is worth a thousand words but it keeps pouring with rain. As soon as it stops I shall drag the bench outside for a photo. In a perfect world I would have a 8-9mm, sharp, round file to make the cut. Leaving only a little material to smooth the curve. The end of the file would be fixed in the end of a length of tube. So I could use the same rest technique as with the emery paper. Unfortunately none of my round files is the correct diameter. More fortunately the clamping curve is hidden from view so the bright bare metal will be completely invisible in use. Rest day.

Click on any image for an enlargement.

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