Difference between an "mtb" and a "racing" bike frame
Discussion
I have found a cheap touring bike for my other half. However it is a "49"cm frame and she is 5' 75in. In the traditional sense of measuring a frame and a person this would be far to too small. However i come from a mtb background where frames are normally smaller than a racing bike frame. I normally ride a 17/18" mtb frame and i am 5'10.
I was looking at a photo of the possible new bike yesterday and comparing it to my 18" Kona smoke (18" frame but with 700c wheels) and the frame looks almost identical in size to my eyes. I am thinking that with a 49cm frame she can have lots of stand over clearance (which she wants) and just use a longer seat post and maybe stem as well.
Yesterday i measured all the bikes at my disposal and nothing made sense when you compared the measured diamensions to the manufactureres specified diamensions. i.e, my 2011 Trek District is a 56cm, measuring from the center of the BB 56cm was half way up the seat post and nowhere near the frame. My 2010 Kona smoke is measured about 44cm bb to top of seat tube. This is almost 18", but if it were a racing bike it would be considered far far to small for someone who is 5'10, however as a mtb its a perfect fit. Is the correct frame size for someone just down to traditional preferences, i.e, roadies like the frame as close to thier balls as possible when standing and mtbers do not?
If you look at the two images below. The first one is the proposed 49cm bike and the second one is my 18" Kona smoke. Both are running 700c wheels and to my eye they look almost the same size.
49cm 2010 Kona Sutra
18" 2010 Kona Smoke
I did a lot of reading and used a lot of frame sized calculators and everything is shouting that a 49cm frame is far to small but i cant see why. Can someone explain it to me and point out where i am going wrong...
Danke,
Confused
.
I was looking at a photo of the possible new bike yesterday and comparing it to my 18" Kona smoke (18" frame but with 700c wheels) and the frame looks almost identical in size to my eyes. I am thinking that with a 49cm frame she can have lots of stand over clearance (which she wants) and just use a longer seat post and maybe stem as well.
Yesterday i measured all the bikes at my disposal and nothing made sense when you compared the measured diamensions to the manufactureres specified diamensions. i.e, my 2011 Trek District is a 56cm, measuring from the center of the BB 56cm was half way up the seat post and nowhere near the frame. My 2010 Kona smoke is measured about 44cm bb to top of seat tube. This is almost 18", but if it were a racing bike it would be considered far far to small for someone who is 5'10, however as a mtb its a perfect fit. Is the correct frame size for someone just down to traditional preferences, i.e, roadies like the frame as close to thier balls as possible when standing and mtbers do not?
If you look at the two images below. The first one is the proposed 49cm bike and the second one is my 18" Kona smoke. Both are running 700c wheels and to my eye they look almost the same size.
49cm 2010 Kona Sutra
18" 2010 Kona Smoke
I did a lot of reading and used a lot of frame sized calculators and everything is shouting that a 49cm frame is far to small but i cant see why. Can someone explain it to me and point out where i am going wrong...
Danke,
Confused
.Im tempted by a 2013 Sutra , but it seems very different to that model.
The Sutra has a lot of MTB about it so is difficult to tell, a lot more than a normal racer or tourer.
I would just try the frame, you could fit a longer seatpost, or longer stem, but these can cause other issues. Ive just seen the bike on ebay, tbh if it goes for the current price its a steal, but much more and I would buy one of the modelss Decathlon offer and get it the right size
Looking @ the Sutra photo, if she is the same height as me it would mean a Very upright position for her . You could fit a longer stem for £30 to stretch it out, but not sure if it would still be too short a reach, but everyone is different
Sometimes on a wrongly sized bike you only notice the issues when you start doing longer rides /using it more.
BTW I'm 5ft7 and have a 19" Kona Mountain and 54.5 Willier racing bike, both are a touch to big , esp the Kona, but as I use it solely for road use I prefer too big over too small
The Sutra has a lot of MTB about it so is difficult to tell, a lot more than a normal racer or tourer.
I would just try the frame, you could fit a longer seatpost, or longer stem, but these can cause other issues. Ive just seen the bike on ebay, tbh if it goes for the current price its a steal, but much more and I would buy one of the modelss Decathlon offer and get it the right size
Looking @ the Sutra photo, if she is the same height as me it would mean a Very upright position for her . You could fit a longer stem for £30 to stretch it out, but not sure if it would still be too short a reach, but everyone is different
Sometimes on a wrongly sized bike you only notice the issues when you start doing longer rides /using it more.
BTW I'm 5ft7 and have a 19" Kona Mountain and 54.5 Willier racing bike, both are a touch to big , esp the Kona, but as I use it solely for road use I prefer too big over too small
Edited by TwistingMyMelon on Thursday 2nd May 13:48
Edited by TwistingMyMelon on Thursday 2nd May 13:50
Don't buy a bike without trying it out for size. All frames are different as manufacturers measure them differently.
This should help you out (I figured you meant to write 5'7.5"):
http://www.ebicycles.com/bicycle-tools/frame-sizer...
This should help you out (I figured you meant to write 5'7.5"):
http://www.ebicycles.com/bicycle-tools/frame-sizer...
I think from what you guys have said and looking again at the pics its the top tube and thus reach that is the problem
from Kona's website
The smoke has a seat tube lenght of 457mm and a top tube lenght of 599mm
The sutra has a seat tube lenght of 490mm and a top tube lenght of 535mm
So the seat tube is longer than the smoke. It comes down to the reach. Can i not make up the extra 4cm with a longer stem?
We are buying the bike blind and from another country so sizing on this particular one isnt possible.
ps, she fits on my smoke just fine.
from Kona's website
The smoke has a seat tube lenght of 457mm and a top tube lenght of 599mm
The sutra has a seat tube lenght of 490mm and a top tube lenght of 535mm
So the seat tube is longer than the smoke. It comes down to the reach. Can i not make up the extra 4cm with a longer stem?
We are buying the bike blind and from another country so sizing on this particular one isnt possible.
ps, she fits on my smoke just fine.
Edited by Lord on Thursday 2nd May 17:11
on Thursday 2nd May 17:11Just one more thing.
Out of curiosity i just measured my 2005 Specialized Allez.
Top tube below measures at 54cm, almost the same as the sutra. yet this is a medium bike and fits me at 5'10
And guess what, the seat tube measures bang on 49cm. The frame looks far bigger than the sutra. So someone is telling porkies about their measurements or where they take them from!
Out of curiosity i just measured my 2005 Specialized Allez.
Top tube below measures at 54cm, almost the same as the sutra. yet this is a medium bike and fits me at 5'10
And guess what, the seat tube measures bang on 49cm. The frame looks far bigger than the sutra. So someone is telling porkies about their measurements or where they take them from!
Lord said:
said: I think from what you guys have said and looking again at the pics its the top tube and thus reach that is the problem
from Kona's website
The smoke has a seat tube lenght of 457mm and a top tube lenght of 599mm
The sutra has a seat tube lenght of 490mm and a top tube lenght of 535mm
So the seat tube is longer than the smoke. It comes down to the reach. Can i not make up the extra 4cm with a longer stem?
We are buying the bike blind and from another country so sizing on this particular one isnt possible.
ps, she fits on my smoke just fine.
You could, I shortened my stem from 120m to 90m and it made a difference in the reach, but not an amazing differencefrom Kona's website
The smoke has a seat tube lenght of 457mm and a top tube lenght of 599mm
The sutra has a seat tube lenght of 490mm and a top tube lenght of 535mm
So the seat tube is longer than the smoke. It comes down to the reach. Can i not make up the extra 4cm with a longer stem?
We are buying the bike blind and from another country so sizing on this particular one isnt possible.
ps, she fits on my smoke just fine.
Edited by Lord on Thursday 2nd May 17:11
on Thursday 2nd May 17:11The stem does look quite short, you could also fit bar ends at a low angle to give further reach, not sure how the rest of the Geo of the frame would be affected
Edited by TwistingMyMelon on Thursday 2nd May 17:36
Lord said:
said: Just one more thing.
Out of curiosity i just measured my 2005 Specialized Allez.
Top tube below measures at 54cm, almost the same as the sutra. yet this is a medium bike and fits me at 5'10
And guess what, the seat tube measures bang on 49cm. The frame looks far bigger than the sutra. So someone is telling porkies about their measurements or where they take them from!
The Kona has quite a slopped top tube , whereas the specialized doesn't so much as well as other geo differencesOut of curiosity i just measured my 2005 Specialized Allez.
Top tube below measures at 54cm, almost the same as the sutra. yet this is a medium bike and fits me at 5'10
And guess what, the seat tube measures bang on 49cm. The frame looks far bigger than the sutra. So someone is telling porkies about their measurements or where they take them from!
Gassing Station | Pedal Powered | Top of Page | What's New | My Stuff