1x8, what size chainring?

[ferrus]

I run a 12-30 rear and 34 up front, and only push occasionally. Keeping weight right down [tyres etc] can be worth a gear or so. A nice short chain seems to stay put for me.

 

[Dr S]

Absolutely no problems so far on both my Hei and Frankenshite which both run single at the front. I have made sure the chainline is as good as I can get it and the chains are as short as I can get away with, but I use no retention devices. Only once has the chain fallen off but I had fallen off twenty yards or so before anyway so it didn't really matter.

Oh- I'm using long cage mechs on both.

Si

 

[stevek]

Thanks Si.

 

[W W Biffta]

ive been trying to decide the same thing for a while. basically i dont think there is a right size/ratio other than the one that works best for you and your ride.
currently i have a 40 ring and 11-30 cassette, just about ok for off road but i run out of gears on the road. 44t+ ring makes even short offroad hills a but of a struggle tho.
crank arm size makes alot of diff too, cant decide on that either.
i think im going to get an oversize cassette sprocket and use a bigger ring. probably works out heavier than having a front mech in the end but i really refuse to ever use one again

 

[Mr Panda]

Wwwwwweeeelllllll - this thread is giving me some ideas :idea: :idea:
Project C/Cone might just end up a 7/8 speeder with front brake only

Question - is it best to obtain a specific single front ring set of cranks, or equally ok to place an approriately sized ring on an old triple set?

 

[reanimation]

Hmmz This is what I'm aiming at for my all weather retro, I was gonna couple a 36t up with a 12-28. Thing is its almost as subjective as the single speed what gear thing. and in the same way it depends on terrain and rider I have 175 cranks and long legs so i feel i can crank it round, and I'm not afraid to push up and go slow down for now! go and try riding everywhere using your current inner ring. I know that my identiti with 12-25 on 40 was useless uphill, of course it was, loved the downhill tho

I'll stress as well ya prob best off with a single speed front ring with full teeth.

 

[W W Biffta]

Question - is it best to obtain a specific single front ring set of cranks, or equally ok to place an approriately sized ring on an old triple set?

like reanimation just said main thing is to get a ring without any ramping on it, but ofc still 8/9 speed.
as far as a tripple crank is concerned, makes no diff so long as the chain line is ok for the gears you mainly use.
problem with the 1x8 setup is you have a compromised chainline at teh extremes. for me i prefer to set up inline with the lower half of the cassette cos theres more torque involved there. maybe using 9 speed components with the thinner chain is a better plan. hmm.
only prob you might have with teh tripple crank is if the chain comes off. it often gets wedged between the bb shell and the bolt posts for the granny ring, real nightmare if its dark and you got no patience.

 

[Andy R]

only prob you might have with teh tripple crank is if the chain comes off. it often gets wedged between the bb shell and the bolt posts for the granny ring, real nightmare if its dark and you got no patience.

Run a bashring in the big ring position and an N-Gear "Jumpstop" on the inside and that'll take care of chain retention.
http://www.billys.co.uk/english/group.php?prod=chng-js

Shown here on a triple set-up but works just as well with one ring.

 

[drystonepaul]

I run 34 surly steel chainring up front and an 8 speed 11-28 cassette. Deore 7spd thumbie with the extra click for the ultimate everlasting drivetrain set-up.

 

[dyna-ti]

42T front 12-32 rear,medium cage