Triple to compact conversions

pottssteve

Hi,

When I bought my first road bike I went for a triple, for a number of reasons. I was a bit unfit, hadn't ridden in years, lived in a hilly area and felt that the granny ring would come in handy. Also, it was before compact doubles were as common as they seem to have become over recent years.

Anyhoo, I'm now older but lighter and fitter. The triple has been used and abused for a number of years so I was thinking of changing to a compact.

I'm not especially mechanically minded so would appreciate a run-down of what would need to be replaced, other than the chainrings. The current set up is Tiagra, so I assume the rear derailleur, chain and shifters would need replacing. Anything else? I would probably go for 105 components as I am happy with these on my other bike.

Thanks in advance for your advice,
Steve

wongataa

To change from a triple to double chainrings you will need to change the chainrings (obviously) and the front shifter. Depending on what you want to change to you may not need to change the derailluer itself but of course a new one could well be needed. If you are changing the chainrings only then provided the new ones work with whatever chain you have then you don't need to touch the rear gears.

shirley_basso

Rear mech and chain both fine.

New chainset, front mech (maybe) and front shifter (maybe).

You may find you can get away with just a new chainset and use the limit screws on the derailleur to stop it overshifting.

janwal

I while ago I had the same conversion done on a 10 speed 105 triple to compact. The LBS just changed the chainrings and a new chain.The shifters worked fine they just adjusted the stop screws on the derailleur.I never had any problems at all,worked perfectly.

imposter2.0

janwal wrote:

I while ago I had the same conversion done on a 10 speed 105 triple to compact. The LBS just changed the chainrings and a new chain.The shifters worked fine they just adjusted the stop screws on the derailleur.I never had any problems at all,worked perfectly.

As above - no need to change the front shifter, just re-adjust the limit screws on the FD.

Bumo_b

Having done this myself, I can confirm you just adjust the limit screws, after obviously changing the chain rings. The old shifters will work fine, as will the front mech.

pottssteve

Hi All,

Thank you for the replies - very useful to know.

Steve

pottssteve

oxoman wrote:

The other more expensive option is to just buy a complete 105 groupset and fit that. Obviously a bit more involved but you will have everything new rather than a few years old and worn. With the newer groupset you could also fit a rear cassette bigger than a 11/28 that was standard up until recently to give you extra bail out if required.

I was also thinking of this. I haven't got enough tools, skill, or skin on my knuckles to do it myself, so I will be going down to the LBS to see what they charge. Current thinking, budget permitting, is to strip the current 105 triple set up off my summer bike and put this onto my older/winter bike, then splash out on a new compact double groupset for the summer bike - maybe 105 again or possibly ultegra (although I doubt the weight and performance gains would warrant the extra price). At the same time, maybe stick an 11-32 rear cassette on the summer bike. Also need new bar tape on the summer bike...

Now, how much will that cost me....?

keef66

You don't need many tools or much skill transferring a shimano groupset from one bike to another. Set of allen keys, some cable cutters, bottom bracket tools. Chain whip and lockring tool for the cassette. Can't think of anything that would skin your knuckles either.

New cables and bar tape £50?
5800 groupset about £360, or wait for the soon to be released 105 R7000?

I'd personally do it all myself, but a lot slower than a professional. I enjoy faffing with all things mechanical though.
Guessing the bike shop will want an extra £200 ish to do both bikes for you?

pottssteve

keef66 wrote:

You don't need many tools or much skill transferring a shimano groupset from one bike to another. Set of allen keys, some cable cutters, bottom bracket tools. Chain whip and lockring tool for the cassette. Can't think of anything that would skin your knuckles either.

New cables and bar tape £50?
5800 groupset about £360, or wait for the soon to be released 105 R7000?

I'd personally do it all myself, but a lot slower than a professional. I enjoy faffing with all things mechanical though.
Guessing the bike shop will want an extra £200 ish to do both bikes for you?

Thanks, Keef,

I have the allen keys and the cable cutters, but nothing else on your list! I bought my first bike at my LBS so have a decent relationship with them. I'm based in Hong Kong so the parts will probably cost a bit more but the labour will be a bit less.
Do we know when the new R7000 is due out?

Cheers,
Steve

keef66

105 R7000 press releases went out at the beginning of April. People expect it to start appearing around June time in the UK. Shimano list it all in their tech docs but so far none of the UK distributors appear to be listing it or taking advance orders.