How long is the stem that you currently use.
The spacers under the stem? Is that 3 cm?
What about saddle height?
Based strictly on stack and reach numbers the 48s seems best. Reach is almost the same and the higher stack would help you get rid of some spacers under the stem. Of course this recommendation has limited value in the absence of information about exactly how your current bike is set up.
You can get some very good advice from the Colnago guys here but it would be best if we could see a photo of your current bike.
My Saddle height is 688mm and spacer height is 30mm and stem 90mm.
The Stem needed to be change between 100mm to 110mm
So do you think 48s still offer better position for me?
Thanks for giving a good advise. In my country I hardly find good bike fit sales rep. Normally they would just sell whatever left in their store.
Im 175cm, 82 cm inseam and im riding C60 50S using Big Cone Spacer, having 12mm of spacers (i'll go for 10 or 8 this days), and using 110mm stem (-7 deg). My saddle setback is 52mm, and seatpost length 72.7 cm
30mm spacers are some higher limit without compromising stiffness of front end, so look like even the frame u ride in this moment is a bit on small side. The reason for this could be they sold u what they have on stock, or maybe u need very short reach or less setback, so compromise is big stack of spacers to have proper reach/setback.
The main difference between 45S and 48S are in reach (u'll need a bit shorter handlebar/stem on 48S, and seatpost with less setback compared to 45S).
I did not understund the length of stem u are using now. Is it 90mm, 100 or 110mm? And what is the reach of the handlebars u use now? Also tell me the setback u have on bike u ride now (including the exact seatpost seatback) and i can compare geometry on 45S, 48S and 50S to the bike u have now so u can choose what suit u best.
If u go 45S compared to ur frame:
- Ull have 28mm spacers under the stem
- Ull need about 5 mm longer reach
- U'll need about 6 mm shorter setback
If u go 48S:
- U'll have 24mm spacers under the stem (which is better then previous case)
- Ull need about the same reach compared to ur frame (maybe 2-3 mm less)
- U'll have the same setback to the frame u have now
This size is very comparable to the size u ride now, even better becase of less spacers under the stem, and if u ride a lot maybe u;ll improve ur flexibility so after some time ull need even less spacers.
If u go 50S:
- U'll have only 5 mm of spacers
- U'll need about 5mm of reach less
- U'll need about 5 mm less setback compared to what u ride now.
I'll give u my final opinion when i know u'r correct stem length and setback u use now, but i'll choose the size which will put saddle in the center to have the setback i need , will have not more then 20mm of spacers (or less), and will put me on 100 or 110 mm stem (better 110)
Probably that will be 48S