Monday 1 September 2008

The Long Way Round - TO IRONBRIDGE by Mike F.

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The Long Way Round to Ironbridge.
What do Grandads do on a dull winter day? Put on their slippers, crank up the heating, light up the pipe, read the papers, do a crossword and be miserable? Not at all. Three of us wheeled out the bikes, donned leathers, gloves, boots and helmets and took the Long Way Round to Ironbridge.
Ewan McGregor and Charley Boorman are the heroes of all bikers who have any “touring” blood in their veins. Having watched the DVD’s and read the books from cover to cover we can but marvel at the enormity of their feat. While that epic trip was what biker dreams are made of I personally have no wish to go there. However what we must not lose sight of is that many bikers were dreaming of “adventures on two wheels” long before these brave lads burst into our lives. We have many reasons or excuses why most never even try to venture beyond the paper shop, Matlock Bath or as far as Devil’s Bridge. Excuses: BMW have been slow in providing us with free bikes, Mitsibushi don’t have a fleet of back-up vehicles ready for us to call on and BBC have not offered to generously fund the trip. Reasons: In my case it is insufficient courage, insufficient energy, and now as an O. A. P. I have the time but I certainly couldn’t fund such a trip. So while I certainly hope Ewan and Charley have awakened the spirit of adventure in thousands of wannabee touring bikers remember many of us had already set out on the road on our own small biking adventures.
Back to our adventure. Tuesday was the day we had chosen to visit Ironbridge. Tuesday dawned, if you can call it that, dull in the extreme. I had to set off from Yorkshire quite early but by 9.30 I had filled up and was shivering at the petrol station on the Markeaton roundabout on outskirts of Derby when John arrived. After brief formalities we set off down the A38 past Derby toward Blithfield to collect Tony. Here we had some fun. Tony is a farmer and lives at the end of a long unmade road/drive. No problem for John’s BMW Adventure but my skittish Aprilia was never meant for motocross nor ankle deep mud. Although the shiny bikes soon took on a brown coating we made it unscathed.
The Aga in Tony’s kitchen plus a huge mug of tea soon warmed us and dulled us into a false sense of comfort. It was short lived and we once again donned the gear and pressed starter buttons. Our grey hair blended well with the grey clouds, grey sky, covering a grey landscape shrouded in grey mist.
The A513 led us past Stafford and then onto the A518 which took us under the M6. On route we passed through several lovely Staffordshire villages such as Gnossal and Newport. The countryside may not be as spectacular as The Peak District but it has it’s own soft charm. Gentle hills create long gentle curves alongside an endless vista of ploughed and planted fields making riding an absolute pleasure. Sheep look miserable on a good day but when they are soggy and “knee” deep in mud words can’t describe them.
The B5062, marked in yellow on the map, was wonderful. Narrow, liberally sprinkled with mud, dung and tractors, it concentrated the mind. At one point frantic waving brought us to a sudden stop. Three fellows, tree fellers, were in the process of dropping a huge dead tree and couldn’t risk any traffic in case it went the “wrong way”! Never a dull moment in the countryside.
We lunched at Shawbury, the site of an R. A. F. base. John said he had been based there for a while during his training as a pilot (World War II ??). A warm welcome in a cosy pub, with hot food and steaming mugs of tea, soon brought a glow to our frozen extremities.
Soon we were back to reality. Well replenished, relieved and with cleaned visors we again set off. .
The B6053, like the B6052, was narrow and muddy but surprisingly free of traffic of any kind. It quickly took us toward Telford where the wide dual carriage-way led us around the city, and by 2.30 p.m. we were parked up opposite the famous Iron Bridge.
Ironbridge revisited.
Small by today’s standards, one has to marvel at the skill of the engineers who had the vision, technical skill and courage to build something so different from anything else at that time. Built in MDLXXIX (translates to 1779) entirely of cast iron. 482 cast iron sections, weighing 483 tons, were complimented by 1736 components, rails, sleepers, wedges etc. Health and Safety scored well. There were no reported injuries reported during the three months it took to complete. Work on the approach roads took much longer and it wasn’t until 1781 that the bridge was opened to traffic.
The return journey took us through Cannock Chase, an area which seems to be about 8 to 10 miles of endless pine forest. A brief appearance of the sun highlighted these beautiful giants reaching toward the sky. So thick and close were the pines that only the slimmest of the sun's weak rays penetrated into the brown undergrowth.
All adventures end. Tony waved and peeled off at Rugeley. John and I opted for the LONG WAY back to Derbyshire: A513, A515, B5234 and then B5017 towards Burton before we rejoined the A38.
In Derby John headed off to Duffield and I continued north to plod the M1 back to Yorkshire.
A great day, cold, wet, bike filthy but infinitely better than pipe ‘n slippers, the papers, telly, a crossword or jigsaw puzzle even if the house is warm and cosy.
That’s what some grandads do.

Tyres - Facts and Friction by Mike F.

Tyres:
In a recent issue of a high quality motorcycle magazine two “facts” were quoted.
First: The tread pattern plays no part in road grip but helps to channel water away from the tyre/road interface to prevent or reduce aquaplaning.
Second: Grip is due to a chemical reaction between the tyre and the road surface.
I understand the fact that the tread does not affect grip as such but channels water out from under the tyre to prevent or reduce aquaplaning. This is illustrated when you compare the grip achieved by “slicks” which have the largest rubber to road contact area and “wet” tyres with a pronounced tread pattern.
As a chemist I am baffled by the hypothesis that the tyre grip is due to a chemical reaction between the tyre and the road surface. I presume the alleged chemical reaction is between the rubber of the tyre and the tarmac surface of the road. As every tyre manufacturer will use a huge range of raw materials in different concentrations in addition to the common basic materials such as rubber hydrocarbon and carbon black. There will be a huge difference in the composition of “hard” high mileage tyres for trucks and vans and “soft” grippy tyres for bikes.
Likewise road surfaces vary according to the composition used. Bitumen is the classic binder used but modern polymers have replaced it in some areas and some roads like the A50 have a concrete surface. SMA (stone mastic asphalt) has been used to give better grip and macro and micro chips are used again to improve grip and hence safety.
These factors make the concept of tyre/road chemical reaction difficult to understand.
My understanding has always been that it is a physical reaction at the tyre / road surface interface where grip “happens”. Friction prevents the tyre surface from moving in relation to the road surface. (Don’t confuse this movement with the rolling action of the wheel.) The weight of the vehicle and gravitational force working vertically force the rubber against the road. Lateral force (centrifugal in case of cornering) acts horizontally. When the latter overtakes the former the tyre will be forced laterally i.e. it will slide. It is the hardness or softness of the tyre that will resist this action to a lesser or greater degree.
Wheel spin (acceleration) and skidding (braking) are other lateral acting forces which will induce tyre/road movement.
Friction is reduced when the surface is smooth, wet or covered with paint, ice or diesel hence the greater the risk of a skid or slide when these factors are present.

Oscar & Grandad Mike F.