Newbie question - single chainrings/cranksets

Giraffoto

I've had my MTB for long enough to take it up and down a few hills, through the mud and over all sorts of rough ground, and in all that time I've never had to use the inner or outer chainrings. The one time I tried the inner for a climb I found my legs whipping into a blur while I was moving slower than I'd walk - so not all that practical - while I don't think I've ever used the outer. So I'm thinking of going single at the front, and I like the idea of doing it on the cheap. What I plan to do is just remove (and keep safe, in case I change my mind) the left-hand shifter, front mech, and inner chainring

Does anyone think this is a terrible idea, and if so, why?

If I decided to get rid of the outer ring as well, is it just a straight swap to replace it with a bash guard?

Does 34t front, 11-34t/9sp rear sound like as many gears as anyone could use?

All advice gratefully received

Chunkers1980

I use all my gears.

Why you removing the shifter and leaving the outer and middle - there's no point in that. It's either one or the other.

Giraffoto

Chunkers1980 wrote:

I use all my gears.

Good point, and plenty of people probably do - but I don't go particularly fast on the roads and I haven't yet found a use for a gear lower than 1:1. Maybe when I start riding in daylight again I'll get more adventurous. As a point of interest, what would you use 22f/34r for? I find that combination too low to be useable

Chunkers1980 also wrote:

Why are you removing the shifter and leaving the outer and middle - there's no point in that. It's either one or the other.

The idea was to remove the shifter and lever (save weight, one less place for the mud to collect), remove the inner ring (bit less weight), but leave the outer in place and only use what was the middle ring. The only reason to leave the outer in place is simplicity - not having to replace it with anything to take up the slack of the chainring bolts, although maybe a bash guard would do this job too.

nicklouse

well you will need to leave the mech on or spend more money adding a guide to keep the chain on which may lead to a new BB and may even lead to new cranks depending on what you have.

either do it right or dont bother.

Giraffoto

nicklouse wrote:

well you will need to leave the mech on or spend more money adding a guide to keep the chain on which may lead to a new BB and may even lead to new cranks depending on what you have.

Is this to imply that it's only the front mech that keeps the chain on the chainrings? I thought the tension in the rear mech was meant to do that. Bear in mind that it's only the front where I'm thinking of shedding gears, the back is going to stay 9-speed (or more)

then nicklouse wrote:

Either do it right or dont bother.

I'm going to write that on the lid of my toolbox

nicklouse

the rear mech can not add tension to the top run of the chain.

if you change to a non rammed chain ring you may find the chain stays on better but it will still come off on the bumps.

Chunkers1980

How do you ride up short steep inclines with very little carry speed? I use my 22f/32r a lot and wouldn't do without it. On a 32t max toothed cassette I wouldn't consider moving from a 3 ring setup. I'd only go 2 ring on 28/40 but would need a 36t rear max.

Saving weight by dropping rings means your bike is so much less do it all.

The Rookie

My commuter running 1x9 on smoothish roads with a single speed specific chainring at the front would still drop the chain when shifting away from the middle of the cassette, you'll need a guide.

the inner ring only adds 'about' 3 more gears, the rest overlap with the gearing available on the middle ring, if you never ever use the inner ring, fine, but if theer is a chance the rest of the overlap is useful in giving you more adapatability without the 'less nice' shift on the front ring.

Simon

Giraffoto

Thanks to everyone who replied - it was definitely worth asking since it turns out that there was a lot that I hadn't thought of. Maybe I'll continue giving that front mech a free ride while I think about it. . .

ilovedirt

You can do it relatively on the cheap to be honest.
Cost of a superstar XCR top-only chain guide, about £17. Should fit most crankset/BB combos, what are you running?
You'd probably need a singlespeed specific chainring as well, about another £20. Some chainring bolts, as you can't run as bash with that guide - about £5. It's not a great deal of money, you just need to know what you're doing. You would also probably need to get rid of the granny ring tabs from your cranks, if you're willing to cut/grind them off, as it's likely they'd foul the guide.

FBM.BMX

You'll need a guie, you should have no problems fitting this one-

http://superstar.tibolts.co.uk/product_ ... cts_id=475

You don't need outer ring to keep chain on with this guide.

Remover shifter/cables/front mech/big and little chainrings.

File down chainring bolts so they fit with single ring.

Ride.

Once chain has stretch/cassette and chainring worn, replace with 11-34 cassette and a non ramped chainring.

Single ring is easy doable, i ride the peaks. You just have to rely more on pushing a gear and getting out of the saddle more. In fact just riding out of the saddle all the time does wonder for your fitness and strength. It's tiring for a month or so, but soon at end of rides when your friends sitting and spinning are dying, you'll still have a surprising amount of energy.

It is mtbing afterall, you should be spending a lot of time out of the saddle working the terrain.

The Northern Monkey

Chunkers1980 wrote:

How do you ride up short steep inclines with very little carry speed? I use my 22f/32r a lot and wouldn't do without it. On a 32t max toothed cassette I wouldn't consider moving from a 3 ring setup. I'd only go 2 ring on 28/40 but would need a 36t rear max.

Saving weight by dropping rings means your bike is so much less do it all.

Big legs?

I get round Cwmcarn ok on my 9sp Canyon!

cooldad

The Northern Monkey wrote:

Chunkers1980 wrote:

How do you ride up short steep inclines with very little carry speed? I use my 22f/32r a lot and wouldn't do without it. On a 32t max toothed cassette I wouldn't consider moving from a 3 ring setup. I'd only go 2 ring on 28/40 but would need a 36t rear max.

Saving weight by dropping rings means your bike is so much less do it all.

Big legs?

I get round Cwmcarn ok on my 9sp Canyon!

But you are a gorilla. I often use 22F/34R with my puny little human legs.

njee20

How do you ride up short steep inclines with very little carry speed? I use my 22f/32r a lot and wouldn't do without it. On a 32t max toothed cassette I wouldn't consider moving from a 3 ring setup. I'd only go 2 ring on 28/40 but would need a 36t rear max.

Saving weight by dropping rings means your bike is so much less do it all.

MORE POWER! Not used smaller than a 28t ring for 6 years, and now on 1x10 with 36t and 11-36. Would quite like a bigger ring for road bits, but nice to have a 1:1 bottom. Bike still does everything I want it to!

Definitely need a guide though. Front mech will work with stop screws adjusted if you really don't want to spend money.

The Rookie

njee20 wrote:

How do you ride up short steep inclines with very little carry speed? I use my 22f/32r a lot and wouldn't do without it. On a 32t max toothed cassette I wouldn't consider moving from a 3 ring setup. I'd only go 2 ring on 28/40 but would need a 36t rear max.

Saving weight by dropping rings means your bike is so much less do it all.

MORE POWER!

What you probably actually mean is more torque.......

To an optimist, a glass is half full, to a pessismist, half empty, but to an engineer the glass is twice as large (heavy, costly - as appropriate) as it needed to be!

Simon

njee20

What you probably actually mean is more torque.......

Not really. Someone doing 60rpm in 22/34 is doing 3.0mph. Even at 40rpm (ie applying more torque) in 36/36 you're still doing 3.1mph, and I don't let my cadence drop that low, so actually it is more power, although I'd possibly spin a higher cadence in some places if I had the gear. The reason I can get up things in a 36t that others couldn't is because I have a better power:weight.

Slow clap for trying to look clever with your engineering pedanticism! :-)

The Rookie

At the same speed your using the same power - I did assume Cooldad was being unnecesarily pessimistic claiming he used 22/34 - but more torque....of course we don't know your relative speeds at all hence my 'probably actually' caveat....IF your going faster you will be delivering more power but also almost certainly producing more torque.

Simon

cooldad

The Beginner wrote:

At the same speed your using the same power - I did assume Cooldad was being unnecesarily pessimistic claiming he used 22/34 - but more torque....of course we don't know your relative speeds at all hence my 'probably actually' caveat....IF your going faster you will be delivering more power but also almost certainly producing more torque.

Simon

Nope I use it a lot. I rely on cunning and guile more than power.

The Rookie

You mean knocking anyone (eveyone) faster off the trail?

Simon

cooldad

The Beginner wrote:

You mean knocking anyone (eveyone) faster off the trail?

Simon

Not everyone is faster, there was that two year old on the balance bike once. Just rode up behind him and said Santa was dead. Left him crumpled in a snivelling heap.

njee20

At the same speed your using the same power

Yes, which is why I used the specific analogy of speed... More significantly I am confident that climbs people are using 22/34 for I can do faster, ergo with a higher power:weight ratio, not necessarily more power.