4 Mar 2015

4th March 2015 11 speeds? Why not?

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The new [gear cable] noodles are the only clean part of my poor trike! Cleaning with soapy water at temperatures hovering around zero for months on end is no fun! The noodles have the advantage that they are self-aligning. As they rotate they obviate oblique cable angles. The downside is that they use up a lot of extra cable. So are best fitted when replacing the inners with new. I checked the clearances as I turned the steering from lock to lock and all seems well.

Tuesday 3rd 36F, 2C, bright but windy. Gusting to 30mph later with potential wintry showers all day. The wind was roaring in one ear and out of the other as I walked up to the woods. Three skylarks went up and started singing. The first I have heard this year. I watched a crow soaring on the uplift wave with its fingers extended as it traversed the face of the woods. It was much quieter under the trees except for the wind in the canopy. A wall of cloud came over and it started spitting with rain. Just turning to a few flakes of snow as I returned.

Only a short ride in rather mixed, wintry weather. Gear changing is much improved thanks to the new noodles reducing friction. Delays in changing up have gone. Resulting in an occasional bang when I was pedalling hard or climbing out of the saddle and changed to a higher gear. I'm leaving the brake cable noodles alone for the moment. I was so horrified by the flash image of the trike that  I spent some time cleaning it! 7 miles pm.

As soon as the weather improves I shall have to spring clean the trike. With a new chain and cassette seriously overdue after a long, wet and salty winter. The 10speed Ultegra has lasted well compared with other cassettes despite rarely enjoying a clean.

With the consideration of urgent replacement of the gear train I am now seriously considering changing to a double chainwheel instead of a triple. I haven't used the 48T outer chainring for as long as I can remember. More often than not the chain is thrown right over and straight onto the crank! Any less lateral adjustment and it won't change or the chain grinds on the cage. I even had to modify the cage to stop the middle chainring being wrecked! So what's the point?

My present 38T middle ring has easily high enough gears on the small end of the 10sp cassette for downhill use. While I only rarely use the 28T inner ring too. So could go with a single ring if it were not for a desire to retain an ultra-low gear for emergencies. You never know when you will really need a granny/crawler gear! For a tourist any higher gears are only a useful luxury for those rare occasions.

I already have an unused Campag 11 speed Athena double front changer. I bought it hoping it would act as a triple but it just hadn't the lateral movement to reach the largest ring. It has a minimum stated ring size of 34t so a 33t should be okay. A 33t inner is as small as one can go with a 110mm PCD double crank.[Spa XD-2 or TD-2 with custom TA rings.]

I thought something like a Spa TD-2 43/33 double might suit with a 12-32t 11sp cassette. These cranks are rather light, quite pretty and don't rapidly show their age like the much more expensive, coloured kit. The TD-2 has all five of its spider arms visible. The XD-2 hides one of them behind the crank with a concealed screw. Prices for these chainsets, fitted with standard ring sizes, make a complete and utter mockery of the weekend warriors expenditure on much heavier bling! 

http://www.spacycles.co.uk/products.php?plid=m2b0s109p2799

http://www.spacycles.co.uk/products.php?plid=m2b0s109p2016

I have been using 160mm cranks for quite a long  time now but have been [deliberately] doing a lot more climbing out of the saddle. I think I might go back to 170mm cranks. The 160s don't really suit "out of the saddle" efforts. They always feel "too small, too round and too smooth." With no additional torque possible by pulling up hard on the pedals to sprint harder as the rider's weight presses down on the other side. Instead of which it feels like I am constantly under-geared even when my speed is dropping from pushing too high a gear! There just isn't time, at the necessarily high cadence, to pull up on the pedals.

It seems that Shimano has added 11 speed kit while my attention was wandering elsewhere. Thier 11-32 x 11 speeds Ultegra cassette costs about £45[equiv] or £30 for the 105 version online. Both need an 11 speed chains at £15, £25 and £30 for 105/Ultegra or Dura-ace. I doubt 10 speed TA chain rings will be a problem the difference in width between 10/11 is so small. [Less than half a millimetre] An 11 speed system should work well with my 11 speed Chorus Ergo levers too. It seems the former incompatibility between different manufacturers gear components has been erased with the arrival of 11 speed. Except that Campagnolo still uses different splines on their free hubs. The special Trykit 2WD freehub will easily take any Shimano cassette, including 11 speed, but is not available for Campag splines.

A 43/33 double chainset with 11-32 11speed sp cassette will give me road speeds from 5 up to nearly 30mph @ 90-95rpm. I find my present 28 x 30 bottom gear too low to be very useful. So 33 x 32 should be fine for climbing walls. A trike is not balance limited at very low speeds so there is never any point in "getting off" on a hill to walk. Pushing a trike uphill is hard work anyway because the rear wheel constantly tries to run you down. If you walk behind it doesn't self steer like a bike. A 30mph top gear capacity is strictly for downhill use these days and I can always pedal faster to go any quicker. 120rpm is no effort at all for somebody used to high 90s average cadence.

Here's a brilliant visual gear calculator where the sprockets and chain rings can be changed simply by dragging them along with the cursor:

http://www.gear-calculator.com/

If you want a triple just drag the left chainwheel onto the scales and then adjust the chainring sizes to taste by sliding them along until the required tooth numbers appear.

Gear-calculator screen shot:

I can still remember working out my gears longhand back in the 1960s  before electronic calculators became commonplace. Now this clever software completely eclipses dry tables and raises usability to a whole new level of sophistication!

Gear inches = [Wheel diameter in inches x No. of chainwheel teeth] / No. of sprocket teeth.
For example: 27" x 48 / 18 = 72" Which used to be a popular gear for fixed gear time trialling.
This was the highest fixed gear allowed for young competitive cyclists and probably led to a lifetime of twiddling. Riding fixed gear in a hilly area is a wonderful way of learning to pedal really fast!

BTW: Gear inches represents the equivalent size of an Ordinary [slang: penny farthing] wheel with fixed cranks and no gears. Before gears were invented the wheel size of the "high wheeler" was limited by the inside leg measurement of the rider. Since the wheel size sets the direct drive [fixed] gear ratio a high cadence [very rapid pedalling] was the order of the day to achieve high speeds. The rider would usually lift their feet off the pedals on steep or long descents. Given the parlous state of the roads at the time "doing a header" was a common occurrence! Yet ironically the large wheel smoothed the rough roads far better than the early safety bicycles and tricycles. Hence the invention of the pneumatic tyre and the sensible standardisation on 26-28" wheels despite some [arguably minor] road improvements over the last century or more.

Wednesday 4th 24F, +1C, breezy, very heavy overcast, light rain. There was some light overnight snow. We have been promised some sunny periods but with wintry showers. The snow is falling heavily now just before 9am. With wintry showers continuing and heavy spray following every vehicle I went for a walk instead of a ride. It stayed dry but very heavily overcast. I spent hours online researching possible 11 speed gear systems and their compatibility. The cost of 10 speed kit is still too similar to 11sp to be worth replacing like with like. Rest day.

Click on any image for an enlargement.
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