Gearing question and thoughts

[chrispidgeon]

OK, I have doen a search but cannot really find out the answer....so sorry if this is a basic query and apologies if I have missed the info in another thread, but...

i will soon be investing in my first road bike, (currently on my Fisher MTB with slicks).

In searching around, I am really unsure what gearing to go for. In other words, do I go triple or compact?

My concern comes from whether or not the compact would have a low enough gear - I have no way of knowing as I can only compare with my MTB, and have never ridden a proper road bike up and big hills.

So, how big a difference are these two ratios:

25 rear / 34 front
25 rear / 30 front

These are what Specialised will come with (Allez Elite Compact or Sport Triple). Will it be a really big and useful difference? I know the only way to tell is by test riding, but not sure I can....

I note that Canondale do their CAAD with a 27/34 on the 105 compact, or a 26/30 on the Tiagra Triple, how different are these?

Anyway, like I say, sorry if this is a boringly repeated question, and indeed if it's in the wrong forum, but I would be very glad of any help.

Riding will be (initially at least ) around Nottinghamshire.

 

[chrispidgeon]

Oh, the chap in Evans said that there are not many UK hills that cannot be climbed with a compact ?!?

 

[gavintc]

It really depends on how old, fat and unfit you are. In my opinion, if you are buying a decent lightweight road bike and are reasonably fit, you will get up almost anything with a compact (50/34). It will probably come with a stock 12-25 cassette. If you are nervous and intend to do some steep hills, fit either a 12-27 (shimano) or a 13-29 (campag) , depending on the groupset. If you are well past 50, have spent the last 20 yrs smoking fags and drinking yourself into a michelin man lookalike, get a triple.

 

[chrispidgeon]

Thanks. I am 40, 6ft2", 88kg, and fairly fit I think.

Gym twice per week, and have been pulling 20-25 miles on my slick shod MTB, although no really massive hills.

I would like to think I could manage on a compact, but don't want to get it wrong!

 

[adscrim]

So, how big a difference are these two ratios:

25 rear / 34 front
25 rear / 30 front

Its roughly an extra gear, if the 25 is off a standard 12-25 cassette. So the 25/34 would be almost the same as running the 30 front on a 23 rear (It's actually part way between 23 and 21).

Edit - come to think of it, the gaps get bigger if you go past 25 so it's more like two extra gears!

 

[chrispidgeon]

I seem to be liking the Spesh Allez bikes too, and note that the tiagra one (elite) only comes as a compact. To get a triple I would need to go to sora (the sport) and I don't fancy the gear shifter on Sora.

Trek 1.5 is available (tiagra) in triple or compact.

 

[chrispidgeon]

Its roughly an extra gear, if the 25 is off a standard 12-25 cassette. So the 25/34 would be almost the same as running the 30 front on a 23 rear (It's actually part way between 23 and 21).

Right ho, so not really a MASSIVE difference?

And what's all this I read about constantly swapping front cogs on compacts? Is this really an issue? I often double shift on my mtb between middle and outer chainrings (rarely use the inner one)

 

[2Loose]

May I ask which side of Nottinghamshire?

If you are nr Mapperley\Gedling then you may well find a hill that can't be climbed (by me) with a compact double...but they are few and far between and a spot of walking for a few minutes isn't so shameful.
Saying that, I have trouble with some of them on my mtb from time to time Fortunately there aren't many 1 in 5 gradients around at all.

I can get up more than 99% of roads with my 34-25 without too much bother, unfortunately my GF lives in the middle of the < 1%.

 

[chrispidgeon]

2Loose, I Live Mapperley top. My usual routes so far involve down into Lamley/Lowdham, Woodborough etc and over to Southwell, or the other way to Colwick. I always have to end with a hill. Carlton Road/Porchester, Spring Lane, Catfoot Lane. None of these strike me as especially steep or long, although that is not to say that I find them easy at this stage lol

 

[andrew_s]

As is, 30/26 triple is only one gear lower than 34/27 compact.
However, with the compact, if it turns out not to be low enough there isn't any easy way to get lower, as 34 is tha smallest chainring that fits a compact chainset, and 27/28 is the largest sprcoket size for a road rear mech. You could go another gear lower by fitting an MTB rear mech and a 34T cassette, but it stops there.
With the triple, you can fit a chainring down to 24T for another couple of gears without any other changes.

Bear in mind that walking up steep hills whilst wearing road shoes isn't easy.

 

[2Loose]

2Loose, I Live Mapperley top. My usual routes so far involve down into Lamley/Lowdham, Woodborough etc and over to Southwell, or the other way to Colwick. I always have to end with a hill. Carlton Road/Porchester, Spring Lane, Catfoot Lane. None of these strike me as especially steep or long, although that is not to say that I find them easy at this stage lol

Carlton\Porchester\Woodborough Road are easy on my compact so you'll have no bother, but a couple of the side streets beside the Punchbowl on Porchester road are often get off and walk for a hundred metres! As are Freda\Perlethorpe Avenue off of Westdale Lane - but apart from those, you'll have no problems with the compact.

Also, Winchester street can be a pig near the top, but can be done without too much bother if you can't detour around it!

Those are the only roads I have any trouble with in all of Notts...so you'll be fine!

ps. I live opposite the Punchbowl so it looks like I ride the same roads as you.

 

[PpPete]

Right ho, so not really a MASSIVE difference?

And what's all this I read about constantly swapping front cogs on compacts? Is this really an issue? I often double shift on my mtb between middle and outer chainrings (rarely use the inner one)

If you dont mind double shifting, then stick with the compact. Personally I prefer to stick with single shifts and stay in the middle ring of my triple for about 80% of my riding. When I'm fresh the "granny" ring is reserved for the steeper hills, but on the last leg of a 200 km Audax, any slight incline (or even a large speed hump) is excuse enough !

 

[chrispidgeon]

Hmm I think then maybe as it's new to me I might go triple. Which means sora on allez sport.

 

[gavintc]

Hmm I think then maybe as it's new to me I might go triple. Which means sora on allez sport.

Better order the sandals, the Carradice bag and the extra long mudguards with the bit of plastic rivetted onto the end as well.

No, I am just being cheeky. I started on a triple for exactly the same reasons as you. It was not long before I was buying my 2nd bike and had by that time the confidence to know that I could use a double chainset. Good luck, the allez sport gets a good name.

 

[gbs]

If yr MTB, with slicks, is geared why not setup yr new bike on the basis of yr MTB on-road experience? Take yr steepest local hill and find a manageable gear and then ensure that yr new groupset offers a lowest ratio that does not exceed that mangeable gear. Perhaps be a little conservative recognising that the road bike probably will take you further afield and for longer periods and that at the end of the day......

Maybe that calls for a large (25T+) cog coupled with yr 34T chain wheel. This will require using a medium size or even long rear mech. IMO, that is a better solution than triple c/ws with 30T granny.

I have both double and triple systems on my 2 road bikes. I prefer the simplicity of the double but sometimes am grateful for the granny.

As for the chap in Evans who said that there are not many UK hills that cannot be climbed with a compact that is typical chain shop b/s. I bet he is skinny and and young!

Best wishes from another 6'2" person with more than 85kg to propel.