Counting teeth

Sometimes I talk to cyclists (by this I mean actual, real people who are cyclists, and not the imaginary people in my head who I address in this blog), and they demonstrate their superiority in all things bike by attempting to discuss with me the number of teeth on the sprocketty things at the back of our respective bikes. These people always know the number of teeth they have on each sprocket, and I never do. Sometimes I have to look to check which bike I am riding.

Obviously these people are geekier than I am about bikes. That people even exist who are geekier about bikes than me might come as a surprise, but it is true, they do (and when I say people, I don't really mean people, I mean men).

I think these people actually consider the gearing of their bikes before they buy them. I tend to buy a bike because I like the colour, or the shiny bits attached to it are aesthetically pleasing in some way, or the man in the shop tells me that it's really great and it's just what I need (they often say that). I have been known to discuss the merits of triples over doubles or compacts with bike shop assistants, but we can usually both tell that neither of us really knows what we are talking about, our eyes glaze over, conversation peters out and I buy the bike anyway just to end the embarrassing silence.

So in an attempt to satisfy my inner geek, to bolster my male pride (seriously dented now that I have admitted in public that I choose bikes entirely on the basis of the colour), and to maintain the impression that I understand these things, I have decided to perform a survey of the number of teeth on all of the sprockets on all of the bikes in the house.

I also think it could be useful to know which gears I use, which combinations I like, and maybe even, why. All of this valuable research will lead me to the conclusion that I need a new bike. Probably.

The result of all this oily tooth counting is summarised in a table. This shows the number of teeth on the chainset, whether double (or compact) or triple, and the number of teeth on the cassette sprockets; these are labelled "front" and "rear" in the table (respectively) for simplicity, and possibly clarity.

The "Gear inches" columns show the gear inches for each gear combination, calculated in the following way:

Gear inches = (F / R) x D

where F is the number of teeth on the front ring, R is the number of teeth on the rear sprocket and D is the wheel diameter in inches, including the tyre.

This is explained, and can be calculated here and here. Wikipedia has a good explanation of gear inches, and its origins for those interested. Although it dates back to the days of the high wheeler (AKA penny farthing), the usefulness of the measure is that it allows you to directly compare gear combinations on different bicycles with different sized wheels.

I've done the calculations for all of the gear combinations, even though I realise that some of them are never used, or at least aren't really sensible to use; big ring at the front to big sprocket at the back being the obvious example.

Bike	Gear manufacturer	Front	Rear	Wheel size	Gear inches
Best road bike	Campag  Veloce / FSA – 2 x 10	50 34	25/23/21/19/17/16/15/14/13/12	700c	52.6/57.2/62.6/69.2/77.4/82.2/87.7/93.9/101.2/109.6 35.8/38.9/42.6/47.1/52.6/55.9/59.6/63.9/68.8/74.5
Old steel  road bike	Shimano RX100 – 2 x 7	52 42	23/21/97/17/15/14/13	700c	59.5/65.1/72.0/80.5/91.2/97.7/105.2 48.0/52.6/58.1/65.0/73.6/78.9/85.0
Tandem	Shimano Deore / Sugino – 3 x 8	48 36 26	30/24/19/17/16/14/12/11	26”	50.5/54.9/60.166.4/74.3/84.2/90.2/97.1/105.2 40.0/43.5/47.6/52.6/58.8/66.6/71.4/76.983.3 29.5/32.0/35.0/38.8/43.3/49.1/52.6/56.7/61.4
Hybrid	Shimano Altura – 3 x 7	42 32 22	28/24/21/18/15/13/11	700c	40.5/47.3/54.0/63.0/75.6/87.2/103.1 30.9/36.0/41.1/48.0/57.6/66.5/78.6 21.2/24.8/28.3/33.0/39.6/45.7/54.0
Modern MTB	Shimano Deore – 3 x 9	44 32 21	32/28/24/21/18/16/14/12/11	26”	35.1/40.1/46.8/53.4/62.3/70.1/80.1/93.5/102.0 25.5/29.1/34.0/38.9/45.3/51.0/58.3/68.0/74.2 16.7/19.1/22.3/25.5/29.8/33.5/38.3/44.6/48.7

 
Once I had counted all of those teeth, tabulated them and calculated the gear inch values, then I needed to think of something to say about them. And I'm not sure what that something is, so I may just be waffling from this point.

The tandem

From what I have read about tandems, especially touring tandems, most people agree that the widest range of gears possible is a good thing, and I haven't seen much convincing evidence for the use of doubles or compact doubles on tandems anywhere that has hills. Some racing tandems are almost certainly excepted.
Given that this isn't a racing tandem, and that I have ambitions to tour, and that I am surrounded by hills, the gear options on my particular tandem look well thought out and appropriate (but purely by chance as I only bought the tandem after I happened to see it in the shop window from the car). There aren't quite the low gears you would get on a true MTB, but I'm not sure I could keep the tandem upright with any lower gearing.

The road bikes

 

I think that I already understood the difference between the road bikes; the old steel bike (an Orbit America from 1991, pretty much as new in terms of build) has an old school double and a 7-speed rear, meaning that the gearing is limited and there are no easy options uphill. A bike for flat country, or more likely, proper hard men. I do love this bike, but I might not quite be up to it.

The new road bike (an alloy Bianchi from 2009) has a compact double, and from the numbers you can see that you get a wider range than the Orbit, both because it's a compact (50/34 compared to the Orbit's 42/52) and because it's a 10-speed. But what makes better sense to me now is why I seem to be changing gear so much, and why those changes are often changes at the front and the back at the same time. The gears are just too far apart and there are often no easy routes between those gears that are close together in terms of gear inches. So that might well explain why on rolling ground, for example, I never seem to be in quite the right gear... And why I don't think a compact double would be my first choice in the future no matter what the marketing men want me to believe.

The hybrid

This is geared pretty much like a mountain bike, but I guess the big wheels make a difference to the gear inches. To be honest it is fine; probably the gears are a bit low, as I spend more time in the big ring than on the other bikes, but given what I use it for, it is OK.

The MTB

This has some very low gears, the kind you struggle to move your legs fast enough for. This seems to sum up the difference between roadies and offroaders. With a road bike the cooler you are the bigger the gear you can push, with an MTB the smaller the gear you can turn without the bike falling over, the cooler you are.

I'm not very good at spinning my legs that quickly, but apart from that this has all the gears I need, and they always seem to be in the right place.

Summary

I'm fairly certain that my perfect all-round bike, for the terrain I currently ride on, would have a triple somewhere in the region of what I have on the tandem.

The obvious alternative, the compact double, looks great on paper, but not so good in real life.

The downside of a triple is the increase in weight, which is small enough for me to live with, the alleged increase in maintenance overhead, which I am not really convinced by, and the sheer unhipness amongst the wannabe racer crew, who I don't care about (especially when they are walking and I'm not).

I wonder how many others would come to this conclusion if they gave it some proper thought and could get away from the attitude that only old men and weaklings needed triples? Or just stopped buying what they were told to buy.

And maybe I should have thought this through before I bought all of those bikes.

What I might do with the hybrid

I currently seem to be suffering from a fortuitous combination of elbow tendinitis and a flu-type virus. The result is a lack of energy, slightly dubious sense of balance and discomfort when I try to grip anything. This means that I don't really want to cycle, run or swim, and even messing around with a screwdriver seems to to be off limits. But I can just about manage to type gently.

This gives me the opportunity to at least think about what I'm going to do with the hybrid, and in what order.

It currently looks like this:

First of all I plan to strip it back down to a bare frame and forks, and have it powder coated, probably in pale blue.

Then I will build it back up with the current components, except for the  headset, front brake, and possibly cables, which will need to be replaced.

Once it is all working again, I plan to replace the existing butterfly bars with some new moustache or Northroad bars like these or these; and I may also fit a new stem at this stage. I do quite like the butterfly bars, but not quite enough not to replace them. They were on the tandem, with the brakes in the more conventional position (at the ends), but I wasn't happy with this. On the tandem I like my hands close to the brakes most of the time, and on the butterfly bars this gives the least sense of control and stability while also losing all of the useful hand positions.

When I put the bars on the hybrid I put the brake levers in the less conventional position you can see in the picture, near to those places where I most often have my hands. This is definitely an improvement, and I can't help but think people choose the other position simply because it is much more difficult getting the levers round the bars into my preferred position.

I will also replace at least the front wheel (but probably both wheels if finances stretch that far), with either proper handmade touring wheels from Spa in Harrogate or a pair from Rose Versand in Germany (cheaper, possibly handmade and probably with a dynamo hub). If I decide not to replace the rear wheel then I will need a new rear cassette (7-speed); If I do replace the rear wheel I will need a new rear cassette (7- or 8- speed, but 8-speed might require a new set of gear levers and maybe even a new rear mech).

By then it will be summer, so I will put off fitting new mudguards (and maybe a rack) until winter is looming once more.

And then it will be complete... unless I maybe get some thumb shifters and then maybe...

The great hybrid bike conversion project

I have a Ridgeback Adventure 502 GS hybrid from the early nineties. I bought it new, to cycle from home to the railway station when I lived in Sheffield (and foolishly worked in Nottingham). I chose it mostly because it was cheap, and not having owned a bike as an adult, I wasn't sure that I would use it at all.

I can't really remember how long I used it for, but it must have been at least a couple of years, almost daily. Then it was off the road for a while having various bits replaced, and it was never quite the same again. I also was expected to wear a suit more often, so the bike became much less convenient than the bus.

Then I passed my driving test at the grand old age of 33, left my job in Nottingham and moved up north where I travelled to work by car.

The bike lived in the shed mostly, and occasionally went to the shops, but no further. Then one day when I rode it to the shop I realised that it wasn't just the weight that was slowing me down (we are not talking about a light bike here, it is heavy steel), in fact it seemed to be like cycling through treacle.

And so the project began. Without me knowing that it was a project really. The problem seemed to lie in the transmission, and more specifically the pedals... or the bottom bracket. So I bought tools, did some reading, removed the BB and found the source of the treacle. I cleaned it, re-greased it and reassembled it. Lovely.

Then I looked at the chainset (crankset) and thought how nasty it was, a bit rusty with the chain rings spot welded together. It was thin and light and sharp. So I replaced it with an Alivio one... a bit better, but not, unfortunately, compatible with the existing BB. So I bought a new cartridge style BB and fitted that.

And then I couldn't get the front mech to change properly, so I replaced that with an Alivio one.

Then I replaced the tyres, decided that I needed a new front wheel (at least) replaced the original straight bars with some butterfly bars I had previously on the tandem, and added some funky (or perhaps not) yellow bar tape. Oh, and a new rear canti brake.

Then I realised I had a bike I could use... and a project.