Ordering a groupset

[ogden]

Hello,

I'm building my first road bike up I've got a giant defy frameset and I've ordered a shimano 105 groupset but I don't know if I've made a mistake as I'm new to this and just went of what people were saying.

I've ordered the following

Shimano 105 (5800) Black 11 Speed Double Groupset
Bottom Bracket
1 x Shimano BB-R60 11 Speed Cups (Ultegra 6800/105 5800) Eng £0.00

Brakes
1 x Shimano 105 Black 5800 Brake Set £0.00

Cassette
1 x Shimano 11 Spd 105 5800 Cassette 11-32 £2.99

Chain
1 x Shimano 11Spd 5800 (HG600 105 Chain) £0.00

Chainset
1 x Shimano 105 Black 5800 11Spd Chainset Compact 170 34/50 £0.00

Front Derailleur
1 x Shimano 105 Black (5800) 11Spd Front Braze-on £0.00

Rear Derailleur
1 x Shimano 105 Black (5800) 11Spd Rear Gear Medium (GS) £3.49

Gear Shifters
1 x Shimano STI Levers 105 Black 5800 11Spd with cables £0.00


Someone has commented saying 170's and a compact??? Are you a midget or something?

Have I made a mistake in what I bought my height is 5.9-5.10?

Thanks

 

[busdennis]

carnt comment on the BB but the rest is ok. Crank length is a preference for the perfect fit but I've rode bikes with short and long cranks and can not really tell, build and enjoy

 

[vickster]

I'm your height, 33" inside leg, size 9 feet, 172.5mm cranks on all bikes, confirmed as correct by a number of fits

I use the same rings and cassette, best for hills

BB, just confirm against what giant use as standard on their frames, ditto that a brace on front mech is right

 

[e-rider]

whether you ride a compact, semi compact or standard double chainset, it makes no difference to crank length which is based on your height and specifically your leg length. I'm 6'2" and use 175mm. At 5'9" I would guess you'd use 172.5, but 170 is okay - the difference is small anyway.

 

[mjr]

I'm about six foot and ride 170s AFAIK. It's by far the most common crank length, isn't it?

 

[Crandoggler]

I am 6ft 1 and use a 172.5 if that helps?

It will be fine.

 

[vickster]

Most 54cm roadbikes for the OPs height seem to have 172.5 as standard?

What size is the frame? Medium presumably?

You can see what giant supply on their bikes here. I can't imagine it's changed in the last few years
https://bikebarn.ucdavis.edu/bikebuy/assets/SB2012_TECH_SPREAD_37_bike-fitting1.pdf

 

[Tim Hall]

Back in the day, crank length used to be determined by the formula

(Inside Leg)/(Inside Leg) - 1.0 + 170mm = Crank Length

I doubt this helps.

 

[MrPie]

Everything looks fine except from there being no Campagnolo

 

[wheresthetorch]

^^ this

 

[boydj]

'Someone' is pretty deluded if he/she thinks there's much noticeable difference between 170, 172.5 or 175 when pedalling.

 

[fossyant]

I'm 5' 9" and use 170mm on 3 bikes and 175 on the MTB. Makes bugger all difference.

 

[HLaB]

I'm 5' 9" and use 170mm on 3 bikes and 175 on the MTB. Makes bugger all difference.

When you've got your bike set up wrong like I did when I started cycling it does . I had my saddle too high and 2.5mm was enough to start pulling my calf muscle too much. That said, Ive been riding 172.5mm cranks for years but was donated an 175mm Ultegra crank and swapping between the two makes bugger all difference, certainly not one I can notice

 

[e-rider]

I can tell if I'm riding 170 or 175 without looking! 172.5 might be more tricky to notice though

 

[briantrumpet]

I'm peddling 175 cranks.

Anyone want to buy them?