Converting a Subway to a double chainring. Madness?

Sleeper Service

The bottom bracket on my Subway is starting to grind, and the chain is rusty, with skipping on the cassette due to wear and tear. The chainring might do another six months, but is looking a bit worse for wear now. Given that I've hammered the b*ll*ocks off it over the last seven months, I'm OK with replacing these bits.

But...

Could I relatively easily replace the triple ring with a Tourney A070 double compact chainset or a Claris. I realise I might have to change the FD, but this should work with my Altus 280 RD, shouldn't it?

t4tomo

A bottom bracket should last more like 7 years than 7 months. I'd replace chain and cassette and see how it goes and then keep the chain clean and lubed.

If you do swap the triple to a double, not sure why you would though, then the FD may be Ok but you would need a new shifter. No issues with the. RD what so ever.

Sleeper Service

A good bottom bracket should, unlike the generic whatever it is that Halfords stuck in there. Apparently this is a fairly common issue with this part.

The shifter should be OK I think, provided I use something like a Shimano RD R440, which is designed for flat bar shifter pull. Thanks for confirming that the RD should be fine.

It's really just an idea bouncing around my head at the moment. I'm equally likely just to do as you say and swap the chain and cassette, and clean the BB.

Cheers again.

The Rookie

No need to change shifter AT ALL, just use 1 and 2 and set the high stop so it doesn't pull the chain right over the large ring.

Halfords OE is a VP or Chin Haur, the VP don't last long, the CH is a good reliable option.

Sleeper Service

Ta. I'm happy enough with the combined shift/brake unit the Subway has (Shimano EF-51) - nice easy shifting and good lever positioning in relation to the shifters - so don't want to change it.

Only other consideration is the FD. The Tourney 191 on it just now is geared for triples with a max outer ring size of 48T. Is it worth trying to fudge it for a 50/34 set up or just springing £20 on an R440 instead?

The Rookie

If the 191 is working on a 48T, it should be fine on a 50T, you may have to move it up the seat tube slightly (and that may be inhibited by bottle cage bosses?), The only slight concern is that the steps in the sideplate are designed for a 10T step (38->48) not a 14T and they may not lign up properly, but that will be easy to find out.

fallenagain

You need the right FD. Even though the cable pull is the same between road and MTB, the throw and position are different. So if you go for a road chainset you'll need to replace the FD with a road double.