triple to single at the front

[alecstilleyedye]

thinking about taking the triple front chainset off the commuter and replacing it with a single-speed crank (will just need to change the bottom bracket).

will the chainline be ok with a wide-range rear cassette?

cheers in advance

 

[T4tomo]

Yes as long as the bottom bracket ends up positioning the single chainring in same plane as the middle ring is currently, I.e slap bang in the middle of your cassette.

 

[T4tomo]

thinking about it you could remove the granny ring, keep the big ring as a chain guard and just use the middle ring with FD removed.

 

[twentysix by twentyfive]

Yes as long as the bottom bracket ends up positioning the single chainring in same plane as the middle ring is currently, I.e slap bang in the middle of your cassette.

+1

Key thing is the BB axle length.

 

[Sharky]

On one of my bikes, went from a double to a single. No need to change the BB, just attach the chain ring in the position which gives the best alignment.
Worth re-calculating the chain length required. If using the "middle" size, you can probably remove a couple of links, which could make it run smoother when on the smaller sprockets. A switch to a "narrow/wide" chain ring will also make it run smooth and reduce the chances of chain drop off.

Once you convert, you'll be surprised how much better it feels. No more changing up with one lever and changing down on the other.

 

[alecstilleyedye]

i guess a 120mm bottom bracket axle length is in order. the ss crankset is considerably lighter than the triple and, as the granny ring requires removing the chainset anyway to remove, may as well take it off completely.

thanks all

 

[Pale Rider]

Worth thinking about clearance, Clarence.

If a bigger ring ends up in the same place as a smaller one is now, it could foul the chainstay when everything is nipped up tight.

 

[alecstilleyedye]

42 currently and 46 single speed, might go for a 122mm bb then…

 

[Pale Rider]

42 currently and 46 single speed, might go for a 122mm bb then…

Sounds like a wise precaution - buying the bits, fitting them and then finding they don't fit would be a nuisance.

I'm no expert, but I am aware Boardman had this problem when they changed a 2X10 bike to a 1X11 for the next model year.

Frame flex could come into it.

If the clearance isn't sufficient, the ring might clear when the bike is standing still, but scrape when you stamp on the pedals.

 

[alecstilleyedye]

Frame flex could come into it.

If the clearance isn't sufficient, the ring might clear when the bike is standing still, but scrape when you stamp on the pedals.

bike will only be for commuting so with a good spread of gears no out of saddle honking required…

 

[Pale Rider]

bike will only be for commuting so with a good spread of gears no out of saddle honking required…

Hopefully all will be well, although I was surprised how little power it took from me to make a frame flex when I was tinkering with a scraping from mech.

It can't have taken much power because I genuinely don't have a lot to deploy.

 

[Elybazza61]

Deffo recommend a narrow/wide chainring,used to have the odd chain drop with the XLS(usually on rougher roads and hacking over speed bumps);got a Hope one and it's been perfect,no chain drops since fitting it.

 

[Origamist]

Could you not just put a narrow/wide chainring in the middle position on your current triple?

 

[jowwy]

Could you not just put a narrow/wide chainring in the middle position on your current triple?

Yes

 

[Profpointy]

Ho about setting the front changer to the middle cog, then just leave it there. Job's a good 'un


.... I'll ge my coat