3x8 to 1x9 or 1x10 options?

[Dadam]

I recently electrified my old Giant hybrid for commuting and I'm thinking of a 1x conversion. It would save a bit of weight (though not a big consideration with the motor). But it would save space on the left bar, much of which is taking up with the unnecessarily large LCD display. Plus I might even be able to use the internal routing through the downtube that currently takes the front gear cable for the LCD wiring instead, which would make it much neater.

Cheapest would be just to change the front ring for a 1x8 but I quite fancy an upgrade to 9 or 10 speed and upgrading the right shifter too. The components are lower end Shimano: Tourney front mech and square taper cranks, Altus shifters, Altus RD. 28/38/48 and 11-32 cassette. Shifting in the rear is fine, but the front is not very smooth despite my best efforts at adjustment. With the motor I don't need such a big range of gears but wouldn't want to be stranded unable to get up a hill if the battery went. I've tried leaving it in middle ring and top ring to get a sense of what might suit and I'm thinking somewhere between the two, so a 40 or 42 narrow/wide up front and 11-36.

 

[All uphill]

Sounds like a good plan to me.

1 x 9 should work well. You will need a spacer behind the cassette, if memory serves me well.

 

[wafter]

Sounds like sacrilege tbh - if I had the choice I'd have triples on most of my gear. Why expend time, effort and money making the bike functionally worse in many ways?

 

[fossyant]

Leave as is. You've got the motor assistance. You'll have bigger gaps between gears changing to a 1x setup. I left my 3 x 7 on my commuter as it is, but changed the cassette to a 13-25. It gives a nice closely spaced gearing, with the option still to get up steep cobbled canal locks in the granny ring. I generally only use the big ring. I have one muddy climb on the way home that I'll use the middle ring if it's slippy.

 

[Dadam]

The problem I have leaving it in the big ring is it just "doesn't like it" Tried adjustments several times but when changing down e.g. to stop at lights it often seems to have shifted fine to a bigger cog, even if I've given a few pedal rotations to make sure the chain seats. But as soon as I put torque onto it, the chain jumps down 1 or 2 cogs which is irritating at best and not ideal if you're mid junction! I'm thinking it's chain line as it doesn't happen on the middle ring, hence a narrow-wide might be less hassle all round.

The bar space is a PITA too. I had to move the bell to the other side and I can't tighten up the LCD clamp fully as the shifter block the allen screw, I have to tighten it just enough then twist the display into position.

 

[Jenkins]

Cheaper option to free up space on the left of the bar - get a Garmin mount which faces the other way and mount it on the right. The electronic display can then be moived a bit inboard.

 

[Dadam]

Thanks but it has a different mount now anyway, off the stem, one of these and I’d prefer to keep the buttons within thumb reach

 

[wafter]

The problem I have leaving it in the big ring is it just "doesn't like it" Tried adjustments several times but when changing down e.g. to stop at lights it often seems to have shifted fine to a bigger cog, even if I've given a few pedal rotations to make sure the chain seats. But as soon as I put torque onto it, the chain jumps down 1 or 2 cogs which is irritating at best and not ideal if you're mid junction! I'm thinking it's chain line as it doesn't happen on the middle ring, hence a narrow-wide might be less hassle all round.

The bar space is a PITA too. I had to move the bell to the other side and I can't tighten up the LCD clamp fully as the shifter block the allen screw, I have to tighten it just enough then twist the display into position.

View attachment 721075

You make a well-reasoned argument. I suspect the 'leccy assist has buggered this up as otherwise you'd typically be in the middle ring for most of the time with a correspondingly better chainline. Rear setup doesn't sound great though. Are you sure there are no wear / setup issues?

I run 3x9 Deore(ish) and it's one of my favourites. As it happens I do have a problem with ghost-shifting on the rear, which I suspect might be a bent hanger - potentially worth looking at yours..?

 

[Dadam]

Cassette and chain were new last summer and it’s had maybe 200 miles since so I don’t think it’s wear. I guess the hangar could be bent, not sure, will check cheers. The elec assist shouldn’t be a factor as it’s a hub motor so no extra torque on the drivetrain but the hub is a little wider, had to spread the fork a little to get it in. Maybe this could have caused and alignment issue.

 

[albion]

Take off the front mech, stick it on the middle ring and see how it goes.
Being electric 8 speed is more than enough. There is also the faff of a new bottom bracket for your eventual chosen single ring.
Electric, you have to learn to take it easy.

 

[I like Skol]

I don't get it? Your gear choice/functionality isn't working so you want to throw it all away and install a compromise set-up rather than fix what is clearly a faulty drivetrain.

But as soon as I put torque onto it, the chain jumps down 1 or 2 cogs which is irritating at best and not ideal if you're mid junction!

This should never happen, just fix it!

Leave as is. You've got the motor assistance. You'll have bigger gaps between gears changing to a 1x setup. I left my 3 x 7 on my commuter as it is, but changed the cassette to a 13-25. It gives a nice closely spaced gearing, with the option still to get up steep cobbled canal locks in the granny ring. I generally only use the big ring. I have one muddy climb on the way home that I'll use the middle ring if it's slippy.

THIS^^^^

My previous commuter was a triple. Sold with 28/38/48 and an 11-32 cassette. I quickly realised that the gearing didn't suit my urban commute as the 32T cassette was overkill and rendered 1/3 of the gears unused. I swapped the cassette out within days and fitted an 11-26 (or later 11-25, whichever was cheapest) and found the gearing perfect. The 38T chainring covered most bases (almost like a 1x) and when the speed crept up the 48T came into play to give that extra edge. The 28T was always there in the background as a 'get out of jail free card' if the legs ever proved unwilling or the hill too steep or I was just carrying too much junk in my panniers at the end of a long day. Probably used that 28T about 6 times a year, but was certainly glad to have it when I did. Compact and semi compact geartrains come with a 34 or 36T small chainring, IMO just that bit too small and 38 or even 40 is probably optimal for general use.

The triple is much maligned nowadays due to fashion and trends, but actually is a great combination as it gives a sensible and flexible double gearset with an emergency triple option should it ever be needed. 1x geartrains will always be a compromise that suit a niche situation or limit the options in a more varied environment, you can't escape the simple fact of maths that a 1x struggles to cover the extremes of challenging climbing and 30mph+

 

[albion]

Yes, a compromise. However it does suit electric which itself is a compromise, speeds above 15mph often being, a waste of time.

 

[I like Skol]

Yes, a compromise. However it does suit electric which itself is a compromise, speeds above 15mph often being, a waste of time.

I can't imagine a world where I would never want to go faster than 15mph on my bicycle, but I accept we are all different....

 

[Dadam]

I don't get it? Your gear choice/functionality isn't working so you want to throw it all away and install a compromise set-up rather than fix what is clearly a faulty drivetrain.

This should never happen, just fix it!

My previous commuter was a triple. Sold with 28/38/48 and an 11-32 cassette. I quickly realised that the gearing didn't suit my urban commute as the 32T cassette was overkill and rendered 1/3 of the gears unused. I swapped the cassette out within days and fitted an 11-26 (or later 11-25, whichever was cheapest) and found the gearing perfect. The 38T chainring covered most bases (almost like a 1x) and when the speed crept up the 48T came into play to give that extra edge. The 28T was always there in the background as a 'get out of jail free card' if the legs ever proved unwilling or the hill too steep or I was just carrying too much junk in my panniers at the end of a long day. Probably used that 28T about 6 times a year, but was certainly glad to have it when I did. Compact and semi compact geartrains come with a 34 or 36T small chainring, IMO just that bit too small and 38 or even 40 is probably optimal for general use.

The triple is much maligned nowadays due to fashion and trends, but actually is a great combination as it gives a sensible and flexible double gearset with an emergency triple option should it ever be needed. 1x geartrains will always be a compromise that suit a niche situation or limit the options in a more varied environment, you can't escape the simple fact of maths that a 1x struggles to cover the extremes of challenging climbing and 30mph+

I agree with much of what you say but the issue I described is not the reason I wanted to change, that is just something I've noticed while leaving it on the big ring to see what gear range suits. It doesn't seem to happen on the middle ring, but I agree it indicates an issue.

The main reason was to get rid of a shifter and cable where there's not much bar area and also have an upgraded rear mech for smoother shifting. And doing this conversion I've learned more bike mechanicking so I want to fiddle!

When it was my only bike I used to ride most places in the middle ring just as you describe, changing up to the big for descents and faster flat bits.

This bike is for my commute which is not long but quite a steep uphill on the way home. Before the conversion the bike was hardly being used as I have a couple other ebikes. The motor is because on some days it is really unpleasant slogging up that hill in the traffic about 6 mph, often into the teeth of the prevailing wind. On the way to work I'll get to 30mph down that bit but freewheeling. There is a flat part later where I'll often pedal up to about 25 for a short while but I can just about do this on the middle. I really don't need to do faster descents on this bike.

So something like 40x11 would be ideal for the top end, just forgoing the top two ratios I never use. At the bottom end a 9 speed cassette with a 36 would keep the other 8 cogs with the same teeth but add a useful bottom gear.