Finally, I get the chance to ride the bike for the first time since it's big service. And remember that I have a new front chainset to help with some of the hills we will be negotiating while riding Lands End to John O'Groats. Much of the ride is going to be manageable even if it is taxing. But the first couple of days are going to burn those legs more than I'm expecting. But now I'm expecting it, does that mean it's going to be harder? Oooh, best stop thinking about it.
Now previously, I explained that my bike had a double front chainset. That's the big cog attached to your pedals. If I was to go back further than that you would find that the Raleigh Equipe was originally made with 12 gears. That's 2 at the front and 6 at the back just to be clear. The number of teeth of the cogs on the freewheel (that's the smaller set of cogs on the back wheel that your chain goes around) ranged from 14 teeth to 24 teeth in 2 teeth increments. So, using the little chart above you should read along the bottom line to 24 (it's not shown but comes after 23... LOL). Then draw a line up to the red line. This represents the lowest gear I could select at the time. Then if you draw a line to the left hand numbers you end up with a number of 1.75 (trust me, it does). What that means is for every one turn of the pedals the back wheel would turn 1.75 times.
Stay with me folks.
About a year ago I added a new freewheel to contain an extra cog with 28 teeth providing a new low gear of 1.5 turns of the back wheel to every turn of the pedals. This provided that little bit more flexibility to make it up Ditchling Beacon. A hill that strikes fear into many folk living in Sussex or even those riding the London to Brighton who did not do their homework!
So, to my new front chainset. What I get is a 30 toothed cog at the front. And this ratio curve is shown in blue on the graph. You can see that each of the front gears overlaps each other in gear ratio terms. Think it of low, mid, and high range of gears. While I now have a lovely range of 21 different gears to select, there are the odd few exact ratio matched. e.g. 1st gear in mid range has the same ratio of 1.5:1 as 4th gear in low range. And 1st gear in high range is almost the same as 6th gear in low range.
I hope you are all following this, I'll be asking questions later!
So you ask, what's it like? Well, with a new low ratio of 1.07:1 I found I couldn't ride my bike. Due to the amount of laughing and giggling as I spun the pedals at breakneck speed and hardly moved an inch! LOL. OK, OK, not quite true. But the almost flat road did make me reach for some higher range gears. For those hills. I actually could not find a hill steep enough that was on my test route. I need to go find a steeper hill.
In summary then, did I make the right choice? Of course I did. Remember that I'll be riding heavy with pannier bags on the back and going up some much larger hills than where I live. I just needed the safety net to be in place to give my knees a break when I need it. The thing about cycling up hills is that the lower the gear the longer it's going to take you and that can be worse than sprinting up it in a higher gear for the shorter hills. How often have you used low ratio in a 4x4? not that often if ever for some of you. But at least you have it should you need it.
Righty, end of lesson. Bring on the hills...
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