Giant Defy 4 - 2014

beski

Hello all,
I am interested in the aforementioned Giant Defy 4 - 2014. I've been into mountain biking for a good few years and have been hankering after a road bike for a few years now. My financial situation has curtailed my interest until now. I've decided on the Giant but I wonder if you could enlighten me of the difference between the compact & the triple ring gearing, are the top & bottom ratios the same but just less gears inbetween on the compact? or is it a bit more complex than that?

Thanks in advance...

ovi

50x39x30 v 34/50, have a look at sheldon browns gear calculator http://sheldonbrown.com/gears/ and type in all the chainring sizes and change the "GEAR UNITS" to MPH @ 90 RPM and it will calculate the speeds for you.
e.g. 25t on the back with 30t on the front(triple) will be 8.4mph but if you change to 34t on the front(compact) it will be 9.6mph

beski

Thanks for your reply ovi, I can't find the triple chainring sizes for the 2014 Giant, found the 2013 one's. Found the gear calculator a bit confusing to be honest. What would you say the difference between the two in laymans terms is (so a numpty can understand! )

Cycling Solicitor

I have had a Defy 4 for three years and it's a good choice. There are a lot of hills where I ride (South Wiltshire) and I spend a lot of time in the smaller cogs. I recommend a triple for the extra gears. They are not fashionable but they'll help you up the hills better because there's a better spread of options. I don't understand the reasons for compacts; if it's weight saving the difference for most of us normal mortals is negligible.

beski

Thanks Solicitor, I'm not sure if I can get the 2014 Defy with a triple but what you say makes sense. I'll need to pop back into my LBS & have a chat with them about it.

dj58

If you look on the GIANT UK/Ireland Website all the Defy 2014 range seem to feature compact 50/34T Chainsets.
Maybe your LBS could convert one to a triple for you, though that would incur additional costs.

beski

Yeah that's what I thought, as stated in my original post though, I'm still not completely sure of the difference between the compact & the triple. I don't want to incur too much additional cost, especially if the gains aren't that much.

dj58

With the triple setup your smallest ring is (30T), 50/39/30T, DEFY 4 uses a 11-32T rear cassette, your lowest gear will be 30T-32T, which gives 24.6 gear inches. With the 50/34T compact double setup and 11-32T rear cassette, your lowest gear will be 34T-32T, which gives 27.9 gear inches. That is not far of a 1 : 1 ratio of 26.3 gear inches,
(one revolution of the crank = one revolution of the rear wheel).

Both setups 50T -11T, give 119.5 gear inches high gear, this assumes a 700x23/ 23-622 tyre/wheel combination and 172.5mm long cranks.

Information taken from http://sheldonbrown.com/gears/

Gear Inches

One of the three comprehensive systems for numbering the gear values for bicycle gears. It is the equivalent diameter of the drive wheel on a high-wheel bicycle. When chain-drive "safety" bikes came in, the same system was used, multiplying the drive wheel diameter by the sprocket ratio. It is very easy to calculate: the diameter of the drive wheel, times the size of the front sprocket divided by the size of the rear sprocket. This gives a convenient two- or three-digit number. The lowest gear on most mountain bikes is around 22-26 inches. The highest gear on road racing bikes is usually around 108-110 inches. Unfortunately, the handwriting is on the wall for all inch-based measurement systems.

You may find that the F34T-R32T setup is low enough for your requirements, it will depend on you level of fitness/ability and the terrain you ride. The bike will be a lot lighter than your MTB. Go visit a GIANT dealer and be sized up with the correct frame, ask for a test ride, some dealers will do this, don't buy until you have sat on the bike and feel happy with it and if at all possible test ride it.

Cupras

I wouldn't buy a bike I hadn't ridden un less I un less building it to my own spec

beski

Thanks DJ58, I have been to my local Giant dealer & sat on/was sized, haven't actually test ridden it though.
Being used to mountain biking & the 3rd (granny) ring, (although not used frequently is useful on occasions) I was just a bit concerned that the lowest gearing would be harder work on the compact compared to a triple.

dj58

Hello beski,

I recently purchased a GIANT Defy 0 2013 model 50/34T compact and 12-28T 10 speed cassette. Compared to my road converted MTB 44/32/20 Triple and 11-24T 7 speed cassette, I find the road bikes lack of weight is a big factor in being able to ride up the same climbs I do on the MTB, with no problem using the 34T-28T setup.

I have swopped the 12-28T for a 12-30T cassette, I'm experimenting with slightly lower gears at the moment.

If you do decide to buy the bike, I would ride it as it is before considering a triple conversion, as you may find you don't need it.

beski

Hi DJ58,

Thanks for your feedback.
Yeah weight does seem like a good consideration, I was also thinking of the lack of drag compared to the knobbly fat tyres aswell! and hopefully the tarmac is smoother than the SDW! (I won't get started on road tax & pot holes! :evil: )
I've already made my mind up and was waiting for stock of the Medium/Large in white to come in, apparently another 2-3 weeks.
After initally toying with getting my LBS to put a triple on, I've come to the conclusion that the 34T-32T set-up should be adequate for my needs, I think.

Just got to wait now

dj58

Hi Beski,

What you will notice with the road bike is how much quicker and easier you will cover the ground for the same amount of effort, than on your MTB. I ride mine on the same routes that I have been riding on the road converted MTB and have cut my times considerably. I think it is down to the lack of weight, taller gearing/700c wheels/tyres and being able to get down on the drops definitely helps.

What you will also notice is the narrow width of the handle bars, feels strange for a while after being used to a 23" wide flat bar/bar ends on the MTB. You are also higher up and the narrow high pressure wheels/tyres feel very different compared to the 26"x1.5s I have on the my MTB. You do need to look out more for potholes and bad road surfaces, loose grit/gravel, spilt diesel, especially on wet roads, mud and wet leaves. The other thing you will notice is the caliper brakes and operating levers, as again these feel a lot different to MTB V rim or Disc brakes and operating levers. Allow yourself more stopping distance until you are used to them.

Having said all that, I'm sure you will adapt to the changes and enjoy your new bike as much as I am mine.

beski

Hi DJ58,

Thanks, I'm sure I will, been really keen to get started and the stock issue is a bit frustrating.
I havn't had a road bike since my early teens so it will be an enjoyable change. I've got an old specialized mountain bike (26x1.9) I use on the roads, which is noticeably easier on tarmac compared to the 26x2.1 knobbly tires on my GT MTB.

The Giant will be a big improvement I'm sure, can't wait 8)

Biomech

I realise this is an old thread, but thought it better than starting a new one

Did you get the Defy 4 in the end? If so, how have you found it? I'm looking at getting one as my first road/real bike