Double or Triple chain rings ?

[Tynan]

fixed is a world away from a double though shirley?

I crawled up Ditchling on my previous hybrid on granny/biggest but I wasn't in good nick, two weeks riding after a six year break

if I did it now I suppose I'd be on 34x26, that's going to be just about alright on a lighter bike with a lighter stronger rider I hope/assume/think

 

[jimboalee]

The mystery will unfold.

1/ Weigh YOUR bike, not my 25 lb Pug.
I use my 25lb Pug as an example.

2/ Reciprocate the weight of YOUR bike, whatever weight it is.
If it's 20lb, the reciprocal will be 0.05, as in Eddy's bike.
If it's 33lb, the reciprocal wil be 0.03, as in a laden tourer.

3/ The equation is SO SIMPLE, even a 13 year old schoolboy like I was could work it.

And last but not least - IT WORKS.

I mentioned Eddy. I said he fitted his bike with the appropriate gearing, but I didn't say he used it!
I mentioned my Mom. Her bike had the gear and she used it.
I mentioned my own bikes. They have the gear and I use them.

Someone mentioned the 15mph on a flat road claim I gave many months ago.
This and the "10% gear" are the stepping stones and milestones to becoming a half decent cyclist.
When I bought my Pug, I fitted a 38 ring because that was what the Elite riders were doing to get them up the hills, and it followed the equation. It was a pretty good roadrace bike, and Mrs Crowther said to me "Jim, you've got the tools now. Lets see you use them properly".

There was NO 'bail out' or 'granny' gear. I had 38 x 23 ( 45" ). I had to build muscle. Lots of struggling in the Cotswolds and Peak District until I could keep the pace of the older riders.
There was no such thing as "I can't". I rode and rode until I could.


Now, it is possible to fit a triple. At my age, that's a blessed relief.
And there are 'Compact' sets 50/36. On a Roadrace bike ???
Come on... The Elite riders didn't get to the Elite class by riding 'Compacts'.

Nuff said.

 

[Steve B]

Nooo, I was not denying the equation was simple to work out. I was asking for the rationale behind using the reciprocal, multiplying by 1000 and so on. All you have done is typed the same using a bold font. This is akin to speaking loudly to foreigners in English when abroad - it doesn't explain anything, just repeats what was said before. No points for showing your workings so far - have another go!

It does occur to me that as a newb to this forum I have walked into an 'in joke' and am taking it far too seriously, but as this is in the beginners forum, and beginners tend to believe what they read from more knowledgeable folk as gospel, some indication of this at this point might well be helpful.

Steve.

 

[4F]

Nooo, I was not denying the equation was simple to work out. I was asking for the rationale behind using the reciprocal, multiplying by 1000 and so on. All you have done is typed the same using a bold font. This is akin to speaking loudly to foreigners in English when abroad - it doesn't explain anything, just repeats what was said before. No points for showing your workings so far - have another go!

It does occur to me that as a newb to this forum I have walked into an 'in joke' and am taking it far too seriously, but as this is in the beginners forum, and beginners tend to believe what they read from more knowledgeable folk as gospel, some indication of this at this point might well be helpful.

Steve.

Hi Steve, I think there are many others here who are interested in this as well. The only in joke being that Jimboalee seems to have an endless wealth of these amazing statistics using all sorts of unusual formula's from bygone days. My favourite to date being putting tyres in the oven as the oven is cooling down from baking a cake (coffee and walnut for the record) as an ease to fitting tight tyres.

 

[Tynan]

I read jimbo's, posts as olde world tradish gospel, it all makes sense even if I don;t understand it

 

[Crackle]

Some of it works some of it doesn't. I think the last one to disproved was the average speed amongst hills to be the same as on the flat. The thing is it works for Jimbo or seems to. Blowed if I can make it work for me though: I still enjoy reading it, though Beginners is perhaps not the best place for it.

 

[jimboalee]

My claims here might be seen to some as 'folklore' from a long forgotten era of cycling they would rather forget and sweep under the carpet.
Years ago, I am not afraid to say, it was a necessity of survival to train oneself so one wouldn't get left behind on the hills. I think that is still true today.
Whatever speed the pack were climbing, you needed to be sure you could keep with them.
Road bikes these days have some low gearing. It probably wouldn't get used because if you resigned yourself to the 30 inch 'granny' gears, you will only look up and see the other riders accelerating away up the hill.
The little equation gives a result which represents the gear you should be able to climb a 10% gradient, without getting too knackered and fall off the back when the others get over the crest.

I was instructed to ( at the tender age of fourteen ) – firstly, get to average more than 15 mph over 100 miles, and secondly, climb a 10% on the gear from the equation at 80 cadence.

Surprisingly, the power requirements for both are very similar.

For Newbs - Whatever type of riding you do, these two objectives ( and it might take years to achieve ) are the primary aims in preparation for five or more decades of enjoyable cycling with a club, in Audax, on Sportives, with your children and then with your grandchildren.

My Mom is not with us any more. She last rode her bike when she was 74. She just about got to sixty years of riding since her first ladies tourer in 1946. As you have read previously, the bike had its low gear adjusted to the result of the 'folklore' equation.

In this modern world of super-duper computers, the youngsters want everything proven with numbers. I did, so I worked it all out (with a sliderule ) and had to admit, the bloke in the bike shop was mysteriously 'right on the money', so-to-speak.

 

[Tynan]

excllent post!

happily I'm not preparing for five decade of riding with a club, phew

 

[jimboalee]

Just for interest, and to marvel at the power of those guys.

Here's that photo of Scarponi's Spesh, all 15.05 lb of it.

This is after a hill finish, I presume due to the chain parked on 39 ring and 14 sprocket. That's 75 bloody inches. What is he on?

For a 15lb bike, the equation gives 66 inches, which is 39 ring and 16 sprocket. He won't have 16. 15 and 17 in that cluster.
He's packed a 23 sprocket which gives him 46" to cover all eventualities.

My 16.5lb SWorks with 2lb of water in bottles has the same gearing, but I NEED the 19 sprocket to get up a long 10%.

 

[yello]

My favourite to date being putting tyres in the oven as the oven is cooling down from baking a cake (coffee and walnut for the record) as an ease to fitting tight tyres.

It's that kind of detail that just tickles me.

 

[rich p]

What is he on? [/B]

.

Well, he was suspended over Puerto, so it's probably blood doping!

Try it Jim, then you can ride any gear you like

 

[Fab Foodie]

Nooo, I was not denying the equation was simple to work out. I was asking for the rationale behind using the reciprocal, multiplying by 1000 and so on. All you have done is typed the same using a bold font. This is akin to speaking loudly to foreigners in English when abroad - it doesn't explain anything, just repeats what was said before. No points for showing your workings so far - have another go!

It does occur to me that as a newb to this forum I have walked into an 'in joke' and am taking it far too seriously, but as this is in the beginners forum, and beginners tend to believe what they read from more knowledgeable folk as gospel, some indication of this at this point might well be helpful.

Steve.

Spot-on.

There's nothing like a bit of pseudo-science to baffle a beginner. I'm sorry Jimbo, but you have to do better if you're gonna put this stuff up as 'truth' and as far as I can see it's just psychobabble, good fun for the old-timers here, but nonsense just the same.

 

[Davidc]

All interesting stuff, and these days I'm riding round on an MTB with a triple, and having to use the whole lot - but I (and I'm sure many others who are a bit long in the tooth) can remember using a single chainring and 5 gears on a freewheel block.

The big difference was having to be very careful in selection of ratios, as you simply couldn't achieve the range that we're all used to now.

The formula posted by jimboalee sounds very much like the one used by the owner of the bike shop I used in the late 1960s/ early 70s. He got the requirement right every time, from rule of thumb formulae and years of experience.

I ended up with 2 rear freewheel blocks, one wide range and one standard, and the tool to change them, and with 2 chainrings. Before setting off on anything serious I had to put the right combination on, and adjust the chain length - with no second chance if it was wrong.

Eventually the cost of a 2 ring front mech came down and the bike turned into a 10 gear machine - it was nicked 8 days later.

 

[jimboalee]

Spot-on.

There's nothing like a bit of pseudo-science to baffle a beginner. I'm sorry Jimbo, but you have to do better if you're gonna put this stuff up as 'truth' and as far as I can see it's just psychobabble, good fun for the old-timers here, but nonsense just the same.

Its your choice whether you believe or not.

Personally, I don't believe Jesus was the 'Son of God',

I don't put up a Christmas tree and don't go to any of their ceremonies.


About my 'mystical' "psychobabble". Maybe it shouldn't be in the 'Beginners' section because I had been riding for eight years before I was indoctrinated into the inner circle of cycling witchcraft - when I was fourteen.
Sorry Newbies - If you are the type who DEMAND proof, remember next December 25th is just another ordinary day.

 

[Steve B]

Ah, the 'because I say so' defence much beloved of parents when telling children what to do

Asking for an explanation and demanding proof are two different things, although if you cannot provide an answer I accept they appear the same.

What has Santa got to do with the weight of my bike, and what gearing does his sleigh use from a standing start on a 10% pitched roof?