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Updated: 29 weeks 1 day ago

Re: One bike for climbing, one for descending?

17 May 2016 - 2:14pm
Marginal gains!

Osmium weighs twice as much as lead, 22.6kg/litre, so if your frame and bottle cages could take it, a couple of bottles of it would add a huge weight to an elite racer on a superlight bike. Assuming you could actually get them on the bike nonchalantly. It might be too much extra weight that it would seriously affect handling, but it would certainly help downhill.

Re: One bike for climbing, one for descending?

16 May 2016 - 6:43pm
They are allowed pretty prepares bike swaps, a number of pros do it on Paris Roubaix for the longer cobbled sections towards the end.

I'd definitely more interested to see what the rules are on taking on 2 "water bottles" full of lead were and whether you could take on enough weight to give a significant advantage...

Re: One bike for climbing, one for descending?

16 May 2016 - 6:43pm
Interesting article Postboxer. I like how they weigh the advantage of the different bike against the time taken to changeover and figure that 15sec net makes it worthwhile!

Re: One bike for climbing, one for descending?

16 May 2016 - 6:39pm
Yes I believe loading up with bottles is a way of adding to momentum.

Kermess Races

15 May 2016 - 9:07pm
My Summer Holiday this year will be in Zeeland and I was hoping to find some Kermess races to watch. Does anyone know of a website where they are posted?

Re: One bike for climbing, one for descending?

15 May 2016 - 5:57pm
I thought Chris Froome did it in 2013, there was debate as to whether the mechanic should have been allowed to give him a push start, as he had elected to swap bikes but had no mechanical problems. Here's an article-

http://velonews.competitor.com/2013/07/ ... ial_295701

I've often wondered whether any bottles and clothing handed to riders at the tops of climbs are really just weights, to give them an advantage descending.

Re: One bike for climbing, one for descending?

14 May 2016 - 11:37pm
I'm pretty sure I saw Sir Brad 'swap' bike cause of a mechanical issue during a TdF mountain ITT but can't find anything on Youtube.

Re: One bike for climbing, one for descending?

14 May 2016 - 10:03pm
My understanding is that the rules don't allow for a pre-prepared changeover - i.e. someone waiting at a pre-arranged spot with a bike - so the rider will have to signal to their team car, which on a mountain stage is a very variable thing time wise as team cars can get stuck some distance behind riders.

The bike change strategy has, however, been used a few times on mountain time trial stages that don't have a summit finish to switch from a climbing bike to a TT bike at the crest of the main/final climb - the rider still has to signal for service but they will have their own car following immediately behind & the changeover will have been pre-planned - to take advantage of the aero advantage of a TT bike on the fast finish.

Rick.

Re: One bike for climbing, one for descending?

14 May 2016 - 3:40pm
That's really interesting. And if it's not a dumb question, is there anything to stop a rider being given the bike with a downhill frame as (s)he crests the mountain? And then, swapping to the uphill bike for the next ascent. Maybe the changeover would cost too much time in a close race.

Re: One bike for climbing, one for descending?

14 May 2016 - 2:34pm
Peugeot used to do it in the 1970s, certainly. If you download a copy of 'The Custom Bicycle' - a wonderful book - from the Classic Rendezvous site...

http://www.classicrendezvous.com/public ... icycle.pdf

...and scroll to page 122, you'll find this (remember this was in the '70s - I've no idea what goes on nowadays, although the first paragraph still holds true):

Most professional riders request the shortest possible chainstays and the smallest frame possible. Frequently, riders select a frame that years ago would have been considered too small for their physique. The popularity of the small frame is simple: the smaller frame is usually stiffer.

The ideal design that Saugier [head of technical research at Peugeot bicyles at the time] and his colleagues use for the professionals is composed of 73- to 73.5-degree angles. They then vary the fork rake [/offset] and the caster [/trail]* for the use of the bicycle. Usually a professional racer will have several bicycles and if possible will have a bicycle with a 30- to 35-mm. caster for climbing compared to a 75-mm. caster for downhills.

Although the shorter wheelbase gives a stiffer ride, there have been problems with high-speed handling, particularly when descending large mountains. To remedy this, Peugeot supplies the team riders with bicycles that have a greater degree of caster for long mountain stages.

At Peugeot, they believe that the caster determines steering ability and stability at high speed. The caster dimension can be increased in basically two ways: by decreasing the head angle or increasing the fork rake. According to Saugier, the ideal for the team professionals is to have 73-degree parallel angles which give the ideal length top tube (this refers to standard-size frames—not the smaller or the larger frames). This is ideal when combined with a fork rake of 35 mm. and a caster of 70 mm. This design is specifically intended for racing, however.

One sentence in the last paragraph isn't quite correct: Caster (trail) can be increased in basically two ways: by decreasing the head angle or decreasing - not increasing - the fork rake. Increasing the fork rake would decrease the trail. It's confusing!

*With bicycles, caster is more commonly referred to as trail, although they're the same thing, just as rake is the same thing as offset.

AFAIK 'optimum' trail for a racing road bike is considered to be around 60 mm - that way you get a jack-of-all-trades, at least for tyre widths from around 23 to 28 mm. Wider tyres have 'pneumatic trail', which means they work better with less geometric trail.

Basically, low trail is more stable when climbing, especially when out of the saddle - the bike tends to be very inert, doesn't respond to lean, just steering, and as long as you don't steer, it tends to stay straight and go nowhere other than up - whereas high trail is more stable and less twitchy at high speed - motorcycles have around 80 mm of trail, but their speed parameters are obviously a lot higher. Mountain bikes work best with high trail, apparently, but you want them to be 'jinky' at low speeds, the opposite of what you want a road bike to be when climbing Mont Ventoux. That's my interpretation of it, anyway, but it's such a complex subject I might be wrong!

If that all sounds like the old Abbott and Costello sketch "Who's On First?" (I hadn't a scooby about any of it myself until a couple of years ago) I'll knock up a couple of illustrations later to show you what high and low trail look like, but I'm away out on the bike now.

The likes of Brucey and 531colin know more about this stuff than me and have vastly more experience, so they might chip in if they see this thread.

(I just hope Peugeot's 1970s set-up wasn't what prompted you to ask the question in the first place, or I've just wasted an awful lot of time!)

One bike for climbing, one for descending?

14 May 2016 - 11:34am
Is there a case for eg Tour riders switching bikes at the top of a climb for the descent? There must be design tweaks that could make a bike better for going down than going up, and vice versa. I'm guessing they would have done it if it were possible. But maybe people have some ideas!

Re: TdF route

5 May 2016 - 7:35pm
I'm not sure the details are public yet.

There should be a route map on this page at some point soon. The climbs in the latter part of of the stage are there & there probably aren't too many alternative ways once you get into the lumpy bits.

Hope that helps.

Rick.

TdF route

4 May 2016 - 8:55pm
Can any one tale me where to find detailed TdF Limoges to Le Lioran route ?
Thanks Roy

Re: Very disappointed with ITV4

2 May 2016 - 12:27pm
Tiberius wrote:I live in Scarborough (Hurrrrrrrahhhh)....I was perched on the grass bank overlooking the finish line yesterday. I know very little about Pro Cycling but I know all about having a good time. Great finish and a great atmosphere within the crowd....Loved it....
Christian Prudhomme (boss of ASO, the organisers of the TdY - plus the TdF & other major races) was impressed by the Yorkshire fans' support by all accounts.

Shame about the technical probelms with the TV coverage. I know it wasn't ITV 4's fault but whoever thought fishing was a suitable substitute with no mention of the technical problems leaves me puzzled. Personally a small white dot in the middle of the screen would have been more interesting!

Rick.

Re: Very disappointed with ITV4

2 May 2016 - 10:57am
I live in Scarborough (Hurrrrrrrahhhh)....I was perched on the grass bank overlooking the finish line yesterday. I know very little about Pro Cycling but I know all about having a good time. Great finish and a great atmosphere within the crowd....Loved it....

Re: Very disappointed with ITV4

2 May 2016 - 10:56am
Couldn't help but think it was terry christian doing the voiceover for the yorkshire bank sponsorship between ad breaks. Good to hear a lancastrian voiceover for the tour de yorkshire sponsors . Geoff Boycott wasn't available.

Re: Very disappointed with ITV4

2 May 2016 - 9:11am
Actually, the thought of the large crowds in Doncaster watching the two guys carp fishing is very funny!

Other than the obvious issues on Saturday I loved the coverage. Thought we got to see more of Yorkshire than last year. I was at the finish line in settle watching the coverage from inside the Naked Man. The only down side was they cut the big screen coverage for a Yorkshire bank advert during the last km.

Until the tdf in Yorkshire I just didn't get pro cycle racing. I'm still not completely convinced but love the street theatre in the TDY events. The finish yesterday was compelling stuff as well.

Re: Very disappointed with ITV4

2 May 2016 - 7:57am
Well, Sunday's stage was a bit of a cracker! Might not have had all the big names but was just as enjoyable as many of the Classics.

Re: Very disappointed with ITV4

2 May 2016 - 12:58am
You think we had it bad watching the 'cycling' on TV saturday, what about the poor guys doing the live TV thing like Ned, Chris and Dave?



https://twitter.com/nedboulting/status/ ... 96/photo/1

Re: Very disappointed with ITV4

1 May 2016 - 6:26pm
For those interested in this sort of thing, here is the offending TV uplink plane(s) up and about today . . . . the other plane you can see (A Socata TB20) was on a similar route and had a French registration, interestingly.

tourdeyorkshire2.jpg
tourdeyorkshire.jpg
 
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