Gearing help

tgotb

Toying with the idea of modifying the gearing on my 20-year-old road bike, and would welcome some advice...

Currently I have a 6-speed 12-21 freewheel with 52/42 on the front. During my commute through Richmond Park into London I rarely get above the 4th gear (42/15?) even when I hit 25mph on the flat, and never use the big ring at all unless I'm intentionally trying to go fast downhill. However I do find hills a struggle; minimum speed with a sensible cadence is around 15mph. Whilst I can normally get up Sawyer's Hill at around that speed Dark Hill is impossible without coming out of the saddle, and I haven't dared to try Star and Garter Hill. I'd like to go further afield at the weekends, but scared to go anywhere with a decent gradient; I can actually get up steeper hills on the Brompton, which seems a bit silly. Am I just being a big girl's blouse?

As far as I can see, my options are:

1. MTFU and stop complaining...
2. Get smaller rings (but how much smaller? Is there a minimum size for the big ring?)
3. Get a wider-range freewheel (except I'd like to maintain the close gap between ratios)
4. Switch to a triple chainset (think the front mech can handle this, not sure about the rear one)
5. Switch to an 8- or 9-speed freewheel/freehub (but that presumably means new hub, new shifters and new rear mech too, even if it's possible with the existing frame)

Any advice gratefully received!

flicksta

You are going to find a 6 speed freewheel pretty hard to find, and as you say you will lose your close ratio.

Surely just a compact chainset will do the job 50/34 or something.

will3

Sounds like a compact would work better for you.
I don;t think 9 speed will be an option as your frame is likely 125mm between dropouts and 9speed will need 130mm, although if it's a steel frame, you might be able to have it re-spaced.
The main problem you will have with a compact is that the jump between chainrings is much much more than you have now, so you'll probably need to go end-to-end of your freewheel as you change rings.

will3

or possibly just get a bigger geared freewheel:

http://www.sjscycles.co.uk/product-Shim ... -18963.htm

(minimum cost change)

wgwarburton

That guy on the Brompton wrote:

Toying with the idea of modifying the gearing on my 20-year-old road bike, and would welcome some advice...
.... Am I just being a big girl's blouse?

No.

As far as I can see, my options are:

1. MTFU and stop complaining...
2. Get smaller rings (but how much smaller? Is there a minimum size for the big ring?)

There's a minimum size for the small ring if you don't change the crank- you need to check the bolt circle diameter (BCD), sometimes incorrectly referred to as Pitch Circle Diameter, to find what will fit.
Unless you have a large (eg 135mm) BCD chainset you should be able to go quite a bit smaller. Ypu may need to dig on eBay, if your chainset is "obsolete".

3. Get a wider-range freewheel (except I'd like to maintain the close gap between ratios)
4. Switch to a triple chainset (think the front mech can handle this, not sure about the rear one)
5. Switch to an 8- or 9-speed freewheel/freehub (but that presumably means new hub, new shifters and new rear mech too, even if it's possible with the existing frame)

Any advice gratefully received!

I'd look at which bits are closest to wearing out and change them. A triple chainset would probably give you most of what you want, but if you don't use the big ring (and with a 12T small sprocket, why would you?), I'd be inclined to go to a smaller double, to take advantage of your close-ratio freewheel and avoid changing the whole drivetrain.
If you go too far with chainwheel differences or larger rear sprockets, you might hit the limitations of your derailleurs to cope with chain length, alignment etc.

A 36/46 combo, or something similar (34/44? 34/48?) would probably work for you. If you are feeling geeky you can play with gear charts to work out which gears you use most and how to get the ones you want but beware... many hours can be spent in fruitless speculation!!

Cheers,
W.