Double or Triple chain rings ?

[Chris James]

Uh!

1 in 10. 1 m rise every 10 m progression.

Oh, I see. You've got the wrong end of the stick again.

Jimboalee, Crackle was joking!

As far as road signage goes, I came off on ice just after that 10% sign so it was well placed in that case. Althoguh it wasn't the steepness that was the problem, it was the inch thick black ice from a leaking water main. Although I suppose the steepness contributed to me not being able to stop before I hit the ice!

 

[jimboalee]

I don't mind jimboalee's formula's, I'd wish he'd just admit they aren't remotely applicable to the average cyclist and certainly not a beginner. If they were something to aim for rather than a baseline I think they'd be about right.

On a bike that is designed to be used on a tarmac surface ( so that counts out MTBs ) and set up to correct rider position, it has been laboratory proven that to maintain 12.5 mph on the flat through calm air takes approx 80 Watts.
15 mph requires approx 100 Watts and 18.5 mph requires approx 145 Watts.

A beginner should be able to output 100 Watts to get along at 15 mph.
After a few weeks, 145 Watts output should be manageable.

DON'T think this is 'on the road'. Its on a track under research conditions.

If after a few weeks riding, the beginner decides to tackle a 10% gradient, the 145 Watts will get him up the hill if he has a gear which lets him turn the pedals at 70 - 75 rpm.

If he finds he can wind his way up a 10% at 70 - 75 cadence and not have to lie down at the summit, he's now an average cyclist.

 

[rich p]

.

DON'T think this is 'on the road'. Its on a track under research conditions.
.

Righto

 

[marinyork]

On a bike that is designed to be used on a tarmac surface ( so that counts out MTBs ) and set up to correct rider position, it has been laboratory proven that to maintain 12.5 mph on the flat through calm air takes approx 80 Watts.
15 mph requires approx 100 Watts and 18.5 mph requires approx 145 Watts.

A beginner should be able to output 100 Watts to get along at 15 mph.
After a few weeks, 145 Watts output should be manageable.

DON'T think this is 'on the road'. Its on a track under research conditions.

If after a few weeks riding, the beginner decides to tackle a 10% gradient, the 145 Watts will get him up the hill if he has a gear which lets him turn the pedals at 70 - 75 rpm.

If he finds he can wind his way up a 10% at 70 - 75 cadence and not have to lie down at the summit, he's now an average cyclist.

What's the point in using an idealised situation unless there's no reference to how this even crudely relates to real life road conditions? I daresay I could actually do 15mph on a racetrack on a trackbike, with much narrower tyres on the flat. What I'm much more interested in is what this would relate to in real life situations? 12mph on the flat? 14mph on the flat in the countryside with few junctions and traffic lights? 9mph on urban rolling or hilly terrain?

Over the last few months I've tried and tried to get anywhere near this mythical 15mph on my 12.5 mile training loop. I think it's fictional and that it would only physically be possible for a club level cyclist to do it on a road bike. The fastest I've managed has been greater than or equal to 13.4mph (that may have been 13.9 as the speedo was playing up). To get an average this high requires cruising along at 19 or 20mph and then flooring it on the straights to anything upto 25mph.

 

[MacB]

Jim, I think argumentative is the wrong term(am I being argumentative saying that?) I would class it more as exploratory. Despite failing to elucidate on some aspects of your 'trade secrets' you have shed some further light on your methodology. The gaping holes are around the assumptions, but I genuinely think you have no idea of just how unfit some beginners are.

I've already indicated the improvements I've seen in 3 months, 13 inch larger low gear and 5mph average increase, but these don't make me fast or a strong rider. This is just the result of weight loss, gains in general fitness and improvements in riding techniques. I'm now starting to approach the fitness level you've allocated, in your machinations, as a start point for a total beginner. It's taken me 1000 miles of cycling to get near your mythical start point. I have a totally different understanding of cycling now than before and I have learnt a fair bit from your own posts.

Look around next time you're out shopping, we're not becoming a nation of lardy arses with the sort of base level fitness you assume. It can take decades of dedication to the sofa, TV and takeaways to attain some of these physiques.

 

[jimboalee]

Further explanation.

Evaluating a rider on the track, on his/her road spec machine is done so that successive sessions are repeatable, as far as meteorological and surface conditions are concerned.
This is why many cyclists buy Turbo trainers. They can be set up to negate the many interferences encountered on the road.

Don't put yourself down. If you've been cycling for a couple of months, and I know you've been cycling for longer than that, you will certainly have the ability to get the 145 Watts for a ride round a velodrome at 18 mph.
145 Watts is HALF the power required to walk up a flight of stairs
This is why the 'stair climb' machine in the gym is bloody brilliant.


"Argumentative" was the incorrect word.
"Suspicious" and "Sceptical" might have been better.
"Doubting" and "Disbelieving" even more apt.

The simple 'bottom line' is :-

I cannot find a scientific, rational explanation to why the formula works, it just does.
After trawling through books, University papers and many issues of Cycling Weekly, I carried out some preliminary tests to compare myself to the published figures, applied the research results to the rudimentary physics and the results for gear ratios were surprisingly similar.


In retrospect, the reaction from my learned colleagues was entirely justified. They had never seen this before and were 'sceptical', as should have been expected.

As for 'Trade secrets', have you ever had a Golf lesson? I paid loads of lolly having lessons and wasn't told a fundemental 'trade secret' about the way you HOLD THE CLUB.
In all walks of life, especially competative sports where money is involved, 'trade secrets' are hard to persuade out of the professional.

As for misleading the beginner. The cute LBS man does that admirably. He WILL sell you a Madone ( or should that be Mad one ) 6.9 even if you are 19 stones; and tell you it will fly.

 

[rich p]

You had a golf lesson and he didn't tell you how to hold the club?

Did you have a driving lesson and not get given the key?

 

[jimboalee]

You had a golf lesson and he didn't tell you how to hold the club?

Did you have a driving lesson and not get given the key?

Yup.

I did some reading and only found Hale Irwin's book explained the 'Grip' properly.
I moved to a different course.

I used to pitch baseball when I was younger. The guy who taught me was too old to play and he kindly showed me the tricks.
I did some reading and found NOTHING in any book describing the tricks I'd been shown.

I was the friend of a bicycle frame builder when I was younger. He explained stuff I can't find on the internet or in any book.
Some of it is leaking onto this forum.

 

[jimboalee]

You had a golf lesson and he didn't tell you how to hold the club?

Did you have a driving lesson and not get given the key?

It's funny you should say that.

I knew a chap who had a fibreglass bodied 5.8 litre Fiat Topolino.
That didn't have a key. Two switches and it was push-started by a Ford Transit.

 

[MacB]

Jim, good analogy with the golf and an area I'm very familiar with. Yep, good and bad professionals abound, with the latter being more prevalent. A constant problem in golf is a pro who teaches via a methodlogy, trying to fit a person to a style rather than tailoring to fit the individual and their abilities. Good basics, posture, grip, stance are important but these can vary a lot more than some pro's would have you believe.

I could take any high handicap golfer and transform their game but only if they're prepared to put in the effort. A lesson is a starting point, the hard work is the practice and nothing else can replace this.

This takes us back to bike gearing, I've had great explanations from yoursefl, Rando, Sheldon Brown's site, and many others. getting out and doing it, working at it and fettling to see what fits you is the final answer.

 

[Auntie Helen]

What size horse are you basing that on. Suffolk punch or a pony ?