2nd January 2016: Shimshramergo swinging arm mods.

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I keep thinking small-ish pulleys could have the rear gear cable wrapped around them in a figure-of-eight. The downtube cable enters hgh up and exits low down to ensure a 1:1.38 pull ratio at the pulley rims. This arrangement also suits the downtube cable entry and under-the-chainstay exit to the cable stop. The resulting friction would stop the cable slipping, retaining the two, correct ratio radii but not damage the cable either. Sharp bends cause premature fraying and make it very difficult to withdraw the cable inner for routine maintenance. Snipping a damaged cable off mid-chainstay leaves nothing left to work with.

I have discussed this before but there is little room for pulleys of useful size if they are fixed one above the other. The main problem is the length of the arm does not allow room for two pulleys of any useful size without the radii going completely haywire. I tried shifting the arm pivot above the front changer clamp, to allow a much longer arm, but it looked much too "busy" even for my tastes. Placing the pulleys side by side on a T-shaped arm might introduce skewed forces unless the cable run was altered to suit.


The image at the top shows a rough drawing with a potential solution on the right. A shorter arm can be used without spoiling the radii of the horizontal entry and exit cable runs. The cable must not slip on its route around the pulleys so the arrangement shown on the right offers much better friction due to the much increased cable wrap. In the shallow system the cable wrap is nearer 270 degrees instead of less than 180 degrees in the arrangement on the left. Both systems demand an extra length of cable but should fall within normal, rear gear cable lengths.

The image on the left shows only 90 degrees of cable wrap per pulley. A considerable reduction in desirable cable retention friction is lost. The cable is very likely to slip unless double cable wraps are used. Double cable wrapping will use up even more useful cable length and may be fiddly to achieve due to natural cable stiffness.

Pulley size seems optimum around 20mm in diameter with an arm length of 100mm. A T-piece bolted to the bottom of the swinging arm, to carry the two pulleys, would provide effortless change of radii and thereby, pull ratio. The T-piece need only to be rotated slightly to raise or lower both pulleys relative to each other and the swinging arm's pivot. The change in pull ratio may be easily calculated from the horizontal entry and exit heights of the pulleys before clamping the T-piece pivot/fixing bolt tight again.

In the image to the right the pulleys are shown rather far apart for clarity. In practice they should almost touch for maximum, ratio setting accuracy, increased cable friction and reduced cable pull error over the ratio arm's complete arc of swing.

R1:R2 must match the change in cable pull-ratio required. Note how R1 is measured to the top of the left pulley and R2 to the bottom. The downtube cable must join the top of the left pulley before being wrapped around the second pulley on the right. The cable finally exits rearward below the chainstay to reach the rear changer, cable stop.

I finally solved the problem of finding suitable pulleys. 20mm blind grommets are made of quite hard rubber with a deep groove around the rim. The extra friction on the cable from being well wrapped around the rubber, while secure in the deep grooves, will ensure the cable does not slip. The grommets are the correct diameter to allow fine adjustment of ratio change via the radii from their rims measured from the upper arm pivot. I pressed washers inside the hollow side of each grommet to stiffen them. This allowed them to be drilled for suitable bolts in the lathe so that I clamp them firmly to the T-piece. The washer will avoid the rubber tearing off in use and ensure they remain round under gear cable tension. More washers could easily be stacked to ensure the grommets are fully supported from the inside. Or alloy bushes turned up if greater lightness is desired.

I like these blind grommets as pulleys because they are easily obtained, are made of long-lived, grippy material and require no machining. Once a suitable supporting washer is pressed into the center a normal hand drill will manage a central hole within any reasonable tolerance for concentricity. The pulleys [grommets] do not rotate but are an easy means to achieve the correct radii without causing damage to the gear cable. No cable clamping should be necessary.

Click on any image for an enlargement.

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2nd January 2016 A martyr to reach.

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Saturday 2nd 36F, 2C, easterly gales, overcast but dry. The weekend forecast is for two days of 20mph base winds. With gusts to 35mph+ and temperatures down to -5C. [23F] Which may sound like a perfect time for a stroll along the beach to those who live in really cold places. Everything is relative. One man's heavy dew is another's 6' of floodwater. On my last walk my route along a field track was blocked by flooding and I had to return the same way. A slight inconvenience compared to having one's home flooded or washed away. I don't know what it is about "there and back" but I strongly dislike having to cover the same ground twice. 

My replacement Ergo levers, ordered from Wiggle on the 15th December, are now expected to be delivered on Monday 4th January. Eighteen days without any tracking and hopping up and down every time we thought there was a van in the drive. It's enough to drive one to distraction! Not to mention weeks of not being able to ride the Trykit. It certainly isn't my idea of instant gratification! My back has been aching continuously since I started riding the Higgins again. Though I did remember to turn over the stem ['bar extension] on the Trykit to lift the 'bars a little without increasing the reach.

The Brooks B17 'Special' has very little adjustment room on the rails. So I just pushed it back as far as it would go. Which was only about another 6mm or 1/4". Every little helps, I suppose. Brooks saddles come from an era when short, pressed steel clamps, sitting on top of narrow steel seat posts, were the norm. The modern trend to all-alloy uses up far more of the rails with clamp length. Which stiffens the rails [removing suspension] as well as reducing any allowances for for-and-aft adjustment.

Modern clamps are mostly crap for micro-adjustment of tilt. The 'teeth' which help to lock the angle of the saddle are simply far too coarse. A strip of tough rubber sandwiched between the toothed surfaces might be an idea. Then the teeth need not coincide but would still grip strongly via the rubber. More backwards progress in cycling technology just to obtain that "clean" look with modern, foolishly narrow, plastic, cutaway saddles. The old cross-bolted and very rust prone, Brooks saddle clamp would catch on the rider's shorts these days. There are backward extended. 'layback' seat-posts, of course, but it seems a bit daft when my Trykit was specifically designed to shorten the reach by being very upright with a short top tube. 

8am and it is still pitch black outside. I may be able to get a walk in if it isn't too bad out there. I badly need some current "landscape" photos. I don't like posting old images or when they are obviously out of season. It feels like cheating unless I am making some technical  point or other. The flat, boring greyness of the continuous overcast doesn't provide any sparkle or interest. An hour and half walk battling the roaring wind under a leaden sky. Proofed shell jackets may be sweaty under the wrong conditions but at least they are completely windproof. It was very exposed out on the fields, so I wore some fleece cycling gloves. Then had to keep my hands balled up into a fists, in the pockets of the jacket, just to keep my hands warm. Though I warmed up nicely after the climb up to to the woods. I had the wind on my back for the last leg and it felt quite comfortable.

This afternoon the temperature is dropping steadily below freezing with 30mph gusts. The chill factor is below -10C in still air. I'd prefer it cold and still! I can add my own forward motion on the trike to achieve any wind chill factor to taste. It is certainly very noticeable as speed increases on descents in cold weather. When it is really cold below -10C it can be very uncomfortable to increase one's speed. I have ridden normal shopping routes at -15C before I had proper clothing and gloves and the pain was incredible. I'm fairly sure that was well into frostbite territory for bare flesh or that which is inadequately protected. A blue nose and black patches on my feet in the bath used to be rather too commonplace back then. A pair of ski goggles can reduce eye watering but are usually far too dark. Presumably for reducing blinding sunshine with masses of eye-damaging UV on bare, glaring snowscapes. Doesn't anybody ever ski under an overcast? Rest day.

Click on any image for an enlargement.

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Ist January 2016. Happy NewYear!

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Friday 1st, 34-38F, 1-3C, clear start then overcast, after overnight frost. Light winds. As I scribble my thoughts, as I wait for morning coffee, it has started raining. Where do I queue for my refund for the forecaster's failure to provide the promised sunshine?

As usual, at this time of year, I am torn between changing "the look" of my blog or keeping what seems to work. Change of appearance, for its own sake, is not progress and in many [commercial] cases seems pointlessly counterproductive.

2015 was a year of record global warmth, for literally month after month. Though there was no heat wave this last year it just seemed milder than usual as winter never really arrived. It was also the wettest year on record for Denmark. And elsewhere too, judging by the awful flooding. It has been much windier and cloudier than in previous years. At least it was according to my subjective gut feeling. Though I have no useful data to substantiate this claim. Overcast conditions directly affects my inspiration to photograph anything which isn't fixed down. Which can easily lead to a gap in the photographic record. Not least for decoration of the text.

2015 was also my lightest tricycling year. At least of the six since I became a born-again tricyclist. With many more rest days than usual, my well under 6000 miles, makes me look a bit lazy to the casual eye. I still haven't manage a century, or 100 miles in a single day. Though I did exceed my [habitual] 80 mile minimum, longest distance ride in a day, yet again. How much more difficult would it be to do the whole 100? It depends on the day and how many hours there are left in it. Long rides are best taken in light or non-extent winds in summer. Finding one of those at any time of year in windy Denmark is like finding a square mile of countryside without a single pig farm.

What I did manage to do last year was to break the habit of going out every single day. I became much more relaxed about it all and no longer had that empty feeling if I hadn't had a decent ride that day. This didn't mean I used the car instead of the trike. So at least my CO2/global warming conscience is clear. My incredibly low annual driving mileage compensates for the endless journeys of my multi-car owning neighbours. Given the cost of taxation, insurance and maintenance of my "elderly" car the cost per mile must be quite terrifying by now! NASA would probably be jealous!

Another year has passed and still no chance of finding another [dirt cheap] rural home to allow us move to a completely new area. We could both do with a complete change of scenery and much more room indoors. Chez Hovel is very unlikely to sell in the current, non-existent, rural Danish, housing market. Which means we are stuck firmly where we are. It could be an idyllic spot if our neighbours on both sides did not illegally burn demolition waste to save money. Their toxic smoke envelopes our home whether the prevailing winds blow from east or west. This is also true for the other neighbours, of course, but their attempts to sell their homes just to escape have come to nothing so far. 

Which all sounds horribly negative when I read this back. I hope I can continue to amuse my readers with my endless rants and [probably frequent] repetitions. My wife does not read my blogs because she says she would have to correct all the errors. While I just call it "artistic license"  while maintaining a fairly clear conscience. Just because the dustbins are out on the road doesn't mean they have to be mentioned or photographed every single day.

It still seems very strange to me that so many people would find my daily activities interesting. If the truth were known I am a humble shopper. One who happens to use a lightweight trike/tricycle to transport myself and the goods I buy, between umpteen rural supermarkets and my rural home. My page view counter suggests that I am approaching 0.3 million. While Google suggests a figure well over 400,000. Both numbers can't be right but it does seem rather a lot for a blog without any topless women or fluffy kittens. Is my "clown on a tricycle" performance so entertaining that I deserve to have 60 followers? I really don't know. Given the average human bod you can't all be here for the same reason. Nor can you all be psychologists hoping for deeper insight to a typically damaged, modern human psyche.

I'll keep on pedaling and ranting and posting pictures as best I can. Even after six years of doing this I still haven't a clue what it is "precisely" which draws people to my blog[s]. If I did, then perhaps I could try harder to improve on what I do. Does the "butterfly effect" of my constantly changing subject matter hold my reader's interest? Or could it be mere escapism? What about deeply felt gratitude that: "There but for the grace... ?" Suit yourselves. You will anyway. ;-)

Which reminds me, I often wish  emoticons were readily available on blogs. Just to ensure the reader understands my meaning more clearly. I often rant with a big grin on my face. Though the smile and the rant are not remotely insincere! It seems that emoticons are just as easily misunderstood as my endless monologues. They might even end up making the text look like cherry cake or a currant bun! Probably just as well I can't fall back on  "smileys" then. But don't hold your breath. ;-)

Grrr! Glorglre is screwing up the composition again. I always leave gaps between paragraphs and today they come along and close them up. I have corrected it several times but still they mess it up when I update!

After rain I had just a late morning ride for 10 miles. Shops and roads quiet. Roads wet.

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