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Magical powers of Tarmac

I seemed to have discovered a road that must have made a pact with the devil to humiliate all cyclists.

I've recently started to really enjoy my quick '1hr fit it in while you can' route, that I can know maintain a constant speed of 32-35 khp (which is fast for my low end bike).

But about 15 miles into the ride I meet the road from hell.
Its totally flat, not open to the wind, doesn't have any traffic lights, and is only about 1km long.

This road has some magical powers which automatically drains all your leg strength, makes your speed drop to 25kph, and generally makes you fell like a little girl a bike with a basket.

The only conclusion I can think of is that as the road goes past infant school, there must be some special 'slowing down' tarmac.

Does such a thing exist, or is it all in my head ?


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    JonhinioJonhinio Posts: 289
    Interesting as I think you might be on to somethign there. When I did Windsor Tir the other week there's abit on Drift Road where all of a sudden it feels like i'm going through treacle. Someone posinted out that is was a different type of tarmac at that point. I went back up ther on a training ride and lo and behold it the same thing happened on the same stretch
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    nivaghnivagh Posts: 595
    Also bus lanes. I drop about 3mph on the Doncaster Quality Bus Corridor (ha, ha ha!!) so I don't use it.
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    ZacniciZacnici Posts: 1,385
    I seem to encounter a strip of the 'magic' tarmac about 3 cms wide every time I go out!
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    shadowone1shadowone1 Posts: 1,408
    Each road has a different make up, it base course, then a waring course. Some are given a high stone content (not the white stones), others are not.
    Even roads with high stone content can appear smoothe, but they give a better degree of grip and are good at shedding water. You need to look at the road and see what sort of surface your going over.

    For example, a shiny new carpark while be brilliant to go over on your bike, very low stone content, low resistance but crap at getting rid of water. Lets face it we don't drive through carparks at 70mph...

    however open roads, need good grip and good water shedding.... hence the stone content help with this but the trade off is that cyclists will feel the resistance. Each road is different depending on the level of traffic. hence why older roads are now breaking up cause they were never designed to take the volume of traffic that we have now.

    Sometimes you'll also see at the side of the road, very little stone content, where its in line with the gulley/drain.

    in essence, you need to look at the road itself.....as I say every road is different.
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    You will probably find that there is a slight optical illusion and you in fact travelling uphill slightly.

    Interesting points about macrotexture on the roads tho, this can also helps to provide the lovely "pneumatic drill effect" that Surrey County Council seem to love. If you would like to try and combat any of this, try and stay in the grooves made by HGV's etc, as these areas are generally smoother due to the fairly abrasive action of their axle weight.
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