langster gearing

[gkerr4]

Hi folks - i have a 2007 langster in the much loved 'rust' colour (no laughing at the back - i like it - thats all that matters!)

it currently has standard gearing - which is the sugino 'comp' chainset with a cnc 'zen' 42 tooth chainset with a 16 tooth fixed cog at the back.

ordinarily this would be fine - but i've buggered up my left knee and need arthroscopy on it to repair / remove a torn meniscus (cartilage injury). I've been advised by the consultant that I can continue cycling if it doesn't cause any pain - which so far seems to be ok - with the proviso that I "don't go daft with it.." i have a surgery date of the 10th of July which seems ages away and if I don't cycle I will turn into a fat bloater.

anyway - i've been avoiding the fixed due to the lack of gear changing since I found out about the injury bu I really miss it so I was thinking of lowering the gearing. I'm not sure though on the technicalities

- is the sugino comp a 130BCD chainset or is it a 'proper' track 144BCD?

and also what would be the bet way of lowering it a little - increase the sprocket to an 18 or 19 tooth? - or go to a 40(ish) chainring?

Any help appreciated - even if you just think I should leave the fixed alone for a bit... :-(

thanks
graham

 

[zimzum42]

[/sitting at back with Peejay]snicker snicker[sitting at back with Peejay]

 

[gkerr4]

oh god - it's started already and i haven't even got an answer on the gearing..

:-)

 

[zimzum42]

had you got a nice bike you would have been happier, therefore less susceptible to injury, and this would not have been a problem

 

[Christopher]

ZZ42 you really are a complete waste of space.

Right. Either way you'll need to add or remove links to the chain. Ribble sell track chains for a fiver. I have some 1/8" spare links (5 or 6) that you can have, but I'm off on 10 days hols this afternoon, back here 13th May.

To change the rear sprocket on a fixed, you will need a lockring spanner (like the Hozan one Planet-X sell - costs £18 but will last for ever) and a chainwhip. As it's an American bike, probably everything will be done up gorilla tight.

For the front, you do need the BCD, doubt it's 144mm as I don't think you can do a 42t chainring in 144mm. The BCD might be written in tiny letters on the chainring, have a look. Anyway Spa cycles do 1/8" chainrings in just about every BCD there is, so think about ordering from there. Hewitt in Leyland have a stack of rings on the wall, you might think about going there. Once you have the new chainring then all you need is an Allen key and possibly a spanner to stop the chainring bolt sleeve from rotating.

Formula for gear inches is (Chainring/sprocket)*26.4, roughly, so you are doing 69 inches currently. 39/16 is 64 inches etc.

It would be cheaper to change the rear, but you need more tools. I have all the tools listed above, let me know if you can wait until I am back and I'll happily meet up and change the sprocket for you. You can have the links anyway...

 

[gkerr4]

wow - how good is that - thanks for the info and offers of help / parts - very kind of you sir.

I don't mind getting the tools though - I have a fairly good toolset for my geared bikes - which I have both shimano and campag bikes - But other than change the bars and saddle i haven't done a lot of work on the langster yet so was unsure of what was required.

I'll check the chainring tonight when I get back from work.


Thanks again,

Graham

 

[Landslide]

Hi Graham, hope the surgery goes well and you're back in action soon.

Re: your injury, I suspect it might be worth getting some more specialist advice. Lowering your gear ratio will mean you're putting less force into getting moving (probably a good thing for your knee), but once you're up to speed, your cadence will be higher for a given speed. I'd wonder if having your legs spin round more for a given distance would be a good thing?
I'm no expert in these matters, but I suspect an expert opinion would be a good thing.

 

[MrGrumpy]

gkerr4

I`ve had the same operation done a few years back however if your still mobile your doing a damm sight better than me as I couldn`t straighten my leg Anyway the cyling will really make a differance to your recovery but I think you would be better riding your geared bike on nice spinny gears, you don`t want to strain that knee joint

 

[gkerr4]

you are probably right :-(

I am still mobile yes - it kind of locks up a bit and hurts coming down the stairs. I can't kneel down or bend my leg properly - but it actually feels good on the bike - it's the walking and standing about in between that hurts it.

I'l stick with the geared bike i think - as you say, it'll allow me to keep the cadence at a sensible rate.

thanks guys!

 

[zimzum42]

ZZ42 you really are a complete waste of space.

If you'd been on the forum for longer than ten minutes you might know the background, but never mind.......

 

[MrGrumpy]

speaking of which, wheres your sidekick the other infamous langster lover

 

[zimzum42]

I reckon Peejay bought an extra rusty langster and got lost riding round Hoxton

 

[gkerr4]

yeah - he'll be far too busy trying to get a good part-ex on his collection of rusty-steel things against a london-langster to read this

:-)

 

[zimzum42]

i think i saw him locking up outside that pub off grays inn road

 

[peejay78]

frustruck got real cross and pious there for a minute.

i have a sugino 75, i know it's not a 42 or whatever, but for what it's worth the bcd is 144.

i'm fairly sure yours is a 130 bcd.

i would strongly recommend you change the back, it's much much cheaper. you can even go as big as 22.

PLUS changing the back has a more significant effect than the front.

speaking of rusty steel, here's one i shelled out for earlier: