Not a Christmas Night Ride to Bognor

[TimO]

Unfortunately, I do need to carry slightly more stuff than I can easily carry in just the back pockets of my jersey, and even more so on a Night Ride like this, where there aren't many people to rely on if you have a mechanical.

With Davy's catastrophic incident, we couldn't actually complete a repair, although even with the more extensive spares that I often carry, I doubt there would have been anything I could have done.

 

[Aperitif]

Apart from his thighs, it looks as though you could have stuffed his bike and most of him in the 'entourage derriere'

 

[Flying Dodo]

We all successfully avoided catseyes and all forms of speed wobbling, thank you very much

Very true. I think we maxed out at a fraction above 28 mph going down Reigate Hill.

 

[TimO]

Incidentally, I was talking to someone about gear ratios, although I have no memory of who it was!

The Red bike has a 50/34 compact two speed chainset, and an SRAM 11-25 10-speed cassette, so I think I was wrong on pretty much all aspects of the sizes!

That does give me between 42 and 120 inches from one extreme to the other, gearing-wise, which should be adequate!

 

[zigzag]

seeing your bike gears shifted to the lowest at hyde park corner, i'd say you need lower gearing for hills.

 

[TimO]

I tend to flip the gears all the way when stopping (with plenty of time) anyway, not because I need to.

It would be difficult to actually extend the range. 50 to 34 teeth on the front is already a pretty big jump, so it wouldn't be sensible to fit a smaller chainring. If I changed the cassette to something with a wider range, I'd probably need to fit a long cage derailleur, which would be expensive, and the gears probably wouldn't change as cleanly.

On a good day (ie not after a FNRttC!) I can cycle a 65" singlespeed up Ditchling, so 42" should be enough to let me get up there, even if it requires a bit of effort. I can't say I noticed even the slightest problem with these ratios on the Bognor route.

 

[StuAff]

Incidentally, I was talking to someone about gear ratios, although I have no memory of who it was!

The Red bike has a 50/34 compact two speed chainset, and an SRAM 11-25 10-speed cassette, so I think I was wrong on pretty much all aspects of the sizes!

That does give me between 42 and 120 inches from one extreme to the other, gearing-wise, which should be adequate!

I think you're a bit out on the bottom end gearing there- should be about 36 inches on 23mm. My setup (12-27, 25mm tyres) gives a range of 33-110.
If for some reason you wanted a long cage mech, SRAM's XX mountain mech (equivalent in specs- and price!- to Red) would go to a 34 or 36 I think, the (much cheaper) wide range Apex & Rival road rear derailleurs will both take 11-32.

 

[TimO]

How odd, I got the gear inches using Sheldon's calculator, and putting the values in again I get the 36" which you quoted, although the top end is stil 120". The gear cluster must have been set to the wrong one, and I didn't notice. I don't think the defaults settings have a 10 speed, 11-25 cassette, so I had to type them in manually, I must have made a typo.

Either way, it's feels plenty easy enough to get up most slopes.

 

[Aperitif]

You're easily over the hill Tim.

 

[frank9755]

Either way, it's feels plenty easy enough to get up most slopes.

That's the main thing!

For the record, you'd only need a long cage mech (or medium cage) if you fitted a triple chainset. Your existing mech would be fine for probably 28T (often can get away with up to 30). If you wanted to put something like an 11-34 on the back then you'd swap for a (short cage) mountain bike mech.

If we want to turn this into a discussion on gear ratios, I'll tell you what I have and why I like it - but I'll save that for another time (or until someone asks)!

 

[frank9755]

Go on, go on, go on.

But it would be off topic. And too much information. And I might have told people it before. And it wouldn't help Tim as he likes the gears he has. I think I'll have to save it for a more appropriate occasion.

 

[frank9755]

Go on, go on, go on.

Found the occasion:
https://www.cyclechat.net/
Knew I wouldn't have to wait too long to get it off my chest!