daredevil

This isn't a true single speed issue but I wasn't sure where else it belonged.

I've got a mid 80's steel road bike that I want to do something with. It used to have downtube shifters and years ago I had it converted to brifters. Now I'm thinking about a single speed, or a single chainring with a cassette. I'm open to suggestions.

Somebody suggested a single cog in back with triple chain rings. Have any of you ever done that or seen a bike like that? Good idea, bad idea, stupid idea?

roadgator

you will have to still have a rear dearailer to take up the chain tension. at that point you might as well put a cable on it and have a regular multispeed.

daredevil

Good point. That's the kind of stuff I'm looking for. Thanks. I can put that idea to bed. Now the choice is a single chain ring with a cassette or a regular SS. My problem with an SS is that I live in the mountains and I'm afraid it wouldn't get much use. Just occasional rail trail riding or whatever.

jeffremer

SS with a low enough gear will get you over plenty of hills and you can always coast down. Some people do single chain rings on their cross bikes and commuters. I guess it lets you ditch the front shifter, FD, and chainring, but I don't really see the point. Simplicity for simplicity's sake?

dynaryder

Someone posted a link to a bike that had a setup like that,only it had a Nexus hub on the rear. Can't remember what model,you'd have to search through the Commuter forum. Shimano makes a tesioner so you run multiple rings up front with an SS rear.

Seems to me you'd do better running a single front ring with a cassette on the rear. Just front rings are going to give you some pretty big jumps in gears.

queerpunk

something like VD's yamaguchi?

max-a-mill

i think a hot idea might be 22x32 in front with like a 16 in back. use a chaintensioner....

then you'd have a "normal" ss mtb ratio and a superlow gear for climbing the STEEP long climbs.

never tried it though, so i can only guess that, in theory, it should work allright.

daredevil

I like it. I have climbs around here where I would be out of the saddle constantly on an SS I think.

Concerning gaps in gearing, that doesn't really concern me. I wouldn't be shifting very often.

max-a-mill

i think you'd want to use a nice tensioner (an old rear d might work best) that keeps the chain nice and tight (storng spring) and can take up all that slack between the two gears easily. i don't think the standard singlespeed tensioner is going to work well for you because it is not desgined to take up that much slack.

wolfbrother

I predict a single speed mountain bike will make you very happy. I built one up last year with a 32x15 ratio (it fit perfectly without a tensioner) and I love it. It kills hills, and it actually forces me to slow down and take in the city a little more. I put it together just for the hell of it, thinking I wouldn't ride it a whole lot, but it has far exceeded my expectations. I've even taken it to work a few times (8.5 miles each way) and they were surprisingly excellent rides.

You can look at it right here : https://velospace.org/node/2696

wolfbrother

you know what? I read "mountains" and "bike" and completely missed that you said it was a road frame. my apologies, but riding single speed is fun and challenging regardless of what kind of bike it is.

jfmckenna

My cyclocross bikes like many others have a single ring up front because it's simpler and usually if you drop a chain it's from shifting the front or bouncing it off. It's less likely to loose a chain on a properly adjusted cog set. I use 8 speed in the back. I live in the mountains too and have a fixed gear ratio just good enough to get over 80% of the climbs. Some are a real struggle but others are OK. It's a bit of a trade off and it's excellent training for strength and a hell of a lot of fun.

seaneee

Why wouldn't you just use a flip flop with two different freewheels, one for climbing and one for sprinting. How long are your dropouts?

Or just could just get a 3sp internal hub.

huerro

You can use two chainrings as long as they are close together and you have long dropouts, but you will not be able to shift on the bike.

I rocked the "Dingle Speed" (as someone around here called it) for a little while with a 42 ring on the outside and a 40 on the inside. I didn't have single chainring bolts. It turns out you can ride just fine, even without the perfect chainline.

Check out the Quickbeam here.

Dicko

if you had a bit of dough you could hook up one of these setups from white industries...

https://www.whiteind.com/ENO-cranks-specs.html

they call it the double double. the idea is that you use either a 38/16 or a 35/19 ratio which both end up having the same chain length. i'm not sure how much that would help though because it would take a fair bit of messing around to change gears.

doofo

oooooh mama

Soil_Sampler

Not roadbikes but, this should give you some ideas.
https://forums.mtbr.com/showthread.ph...iple+chainring

pitboss

I know a few people in the world of Cyclocross that utilize a single chainring/cassette type set-up.

check in that forum area for more info if you choose that path

blickblocks

That's brilliant, I love it!

paulv

On a different note (rear der only) there's a bike on fyxomatosis that I bookmarked some time ago, one chainring and shifter, rear derailleur - but anyone know why the front derailleur would be needed? For the weight of a chainring, cable and shifter one might as well have twice as many gears, or why not drop the front derailleur altogether?

https://www.fyxomatosis.com/news.php?readmore=246

TreeUnit

I thought about doing this. If you want gears, but want to keep the bike simple, Try a Shimano Nexus Multispeed Hub. 7 gears, no deraileurs. It'll cost you at least $150 though

You could also try an Internally Geared Bottom Bracket. Really sweet, but they cost around $500 and have to be imported from Czechokoslovakia

Cynikal 

The only reason for that would be to help keep the chain from dropping off the chain ring. I doubt that would be an issue with only a 5 speed rear cluster but it ain't my bike. I run a single front with an 8 in the rear and I've never had a chain drop.

vobopl

Ehm,
.ch stands for Switzerland.

paulv

Chwizerland

yellowjeep

2 speed fix with the geared bottom bracket?