Frame Sizing Question(s)
08-17-07, 10:39 AM
#1
Senior Member
Thread Starter
Frame Sizing Question(s)
It's been a while since I've dealt with mountain bikes, as I got bitten by the 10 speed bug a few years ago, so please bear with me...
Every MTB I've had in the past was a department store POS, however they generally fit without having to crank the seat post up super high. I have CCM MTB with an OK frame but lousy components and a better LBS type MTB with a questionable frame (rust, unsure about the sizing) and I have no problem swapping over some of the components and wheels to the CCM if need be.
Don't worry, I'm not going for a high performance machine, just a general mess about on trails with the occasional trip the grocery store... What I end up building/rebuilding will do what I have in mind fine.
So, the non-CCM bike has a frame geometry aimed more at being a real MTB... and, I see pictures of bikes here on the site as well as paying attention to the ones I see being ridden in the area - and I see that the seat post is cranked up high, and commonly one's heals are swinging back past the cantilever bosses on the rear stays.
This is where I'm not sure if my road bike experiences are getting in my way - on the bikes I'm used to, having to raise the seat post very high and having my heels swinging past the cantilevers is a clear indication that the frame is entirely too small for the rider. Is this not the case with MTBs?
I've not done a detailed inspection of the CCM yet to see if it will accommodate all the parts I was intending to swap over, and it lacks cantilever bosses so I'm hesitant about using it, as I'll have to source side-pull calipers to replace at least the front brakes because the hardware they used flexes under light loads, I don't trust them enough should I need to make a sudden stop.... So if I can use the other frame, I will.... I'm just suspecting it's too small for me but maybe that's just how it's supposed to look?
....
EDIT: Oops. I was nowhere near the bike in question when I posted this question. The frame indeed does seem to be an adequate size - I've just got my brain stuck in roadie mode. Please disregard these questions.
Every MTB I've had in the past was a department store POS, however they generally fit without having to crank the seat post up super high. I have CCM MTB with an OK frame but lousy components and a better LBS type MTB with a questionable frame (rust, unsure about the sizing) and I have no problem swapping over some of the components and wheels to the CCM if need be.
Don't worry, I'm not going for a high performance machine, just a general mess about on trails with the occasional trip the grocery store... What I end up building/rebuilding will do what I have in mind fine.
So, the non-CCM bike has a frame geometry aimed more at being a real MTB... and, I see pictures of bikes here on the site as well as paying attention to the ones I see being ridden in the area - and I see that the seat post is cranked up high, and commonly one's heals are swinging back past the cantilever bosses on the rear stays.
This is where I'm not sure if my road bike experiences are getting in my way - on the bikes I'm used to, having to raise the seat post very high and having my heels swinging past the cantilevers is a clear indication that the frame is entirely too small for the rider. Is this not the case with MTBs?
I've not done a detailed inspection of the CCM yet to see if it will accommodate all the parts I was intending to swap over, and it lacks cantilever bosses so I'm hesitant about using it, as I'll have to source side-pull calipers to replace at least the front brakes because the hardware they used flexes under light loads, I don't trust them enough should I need to make a sudden stop.... So if I can use the other frame, I will.... I'm just suspecting it's too small for me but maybe that's just how it's supposed to look?
....
EDIT: Oops. I was nowhere near the bike in question when I posted this question. The frame indeed does seem to be an adequate size - I've just got my brain stuck in roadie mode. Please disregard these questions.
__________________
1980 Sekine RM-40 | 1990 Miyata 1000LT | 1980 Raleigh Sprite Mixte | 1979 Raleigh Grand Prix
1980 Sekine RM-40 | 1990 Miyata 1000LT | 1980 Raleigh Sprite Mixte | 1979 Raleigh Grand Prix
Last edited by Novakane; 08-18-07 at 09:40 AM. Reason: Ignorance
08-17-07, 12:58 PM
#2
Senior Member
Thread Starter
Sorry if that was confusing - the crux of the issue is that one frame I have is a fairly modern geometry which I'm not familiar with. There is a large amount of clearance for the stand-over height (4" - 6") which means the seat tube is right near at it's maximum extension. While pedaling my heels go back past the rear brakes.
What I want to know is if these kind of clearances are normal for a modern mountain bike, or are they signs that the frame is too small for me?
The rest was just ramblings about an older frame I have with totally different clearances, but with a different geometry, so it's causing me confusion as to which frame to rebuild.
What I want to know is if these kind of clearances are normal for a modern mountain bike, or are they signs that the frame is too small for me?
The rest was just ramblings about an older frame I have with totally different clearances, but with a different geometry, so it's causing me confusion as to which frame to rebuild.
__________________
1980 Sekine RM-40 | 1990 Miyata 1000LT | 1980 Raleigh Sprite Mixte | 1979 Raleigh Grand Prix
1980 Sekine RM-40 | 1990 Miyata 1000LT | 1980 Raleigh Sprite Mixte | 1979 Raleigh Grand Prix
