Inexpensive mountain bikes

[laura*]

My Quick has a 50.5 effective top tube, which is pretty good.

So far I have found:

Specialized Myka Sport ... 52.5cm top tube

Specialized Jett Comp ... 53cm top tube

Jamis Trail X2 ... 52.1cm top tube

49cm Top tube ... a Kona Kula

Motobecane ... 52cm top tubes

What are the seat tube angles on these frames? You need to normalize the ETT by the differences in STA.

[goldfinch]

What are the seat tube angles on these frames? You need to normalize the ETT by the differences in STA.

Thanks. Here is the data:

Specialized Myka Sport ... 52.5cm top tube, STA 74 degrees

Specialized Jett Comp ... 53cm top tube, STA 73 degrees

Jamis Trail X2 ... 52.1cm top tube, STA 74 degrees

49cm Top tube ... a Kona Kula, STA 73 degrees

Motobecane ... 52cm top tubes, STA 73 degrees

So, only one degree difference. Does it matter?

[goldfinch]

I see that my well fitting Cannondale Quick has a seat tube angle of 76 degrees to go with the 50.5cm top tube. How does that compare with these other bikes?

[laura*]

I see that my well fitting Cannondale Quick has a seat tube angle of 76 degrees to go with the 50.5cm top tube. How does that compare with these other bikes?

Nominally, one degree of change in the STA results in 1cm change in the effective top tube. The exact number depends upon the seat tube length, so for smaller bikes, the ETT change will be slightly less.

Your 76 degree 50.5cm Quick is equivalent to:

75 degrees 51.5cm
74 degrees 52.5cm
73 degrees 53.5cm

Thus, the Myka is the same length as your Quick, and the others actually a bit shorter except for the Kula which is a lot shorter.

[goldfinch]

Nominally, one degree of change in the STA results in 1cm change in the effective top tube. The exact number depends upon the seat tube length, so for smaller bikes, the ETT change will be slightly less.

Your 76 degree 50.5cm Quick is equivalent to:

75 degrees 51.5cm
74 degrees 52.5cm
73 degrees 53.5cm

Thus, the Myka is the same length as your Quick, and the others actually a bit shorter except for the Kula which is a lot shorter.

Thanks, that is extremely helpful to me!

[Loraura]

I'd say stay away from the 24 inch wheels unless you are really good at front wheel lifts. The larger the wheel circumference, the higher obstacle you can "roll over" rather than have to lift the wheel and place it on top.

For illustration purposes, think of a kids bike tire perpendicular to a curb. See where the curb hits the tire? like halfway up! It's not going to roll over that. It's going to smack into it and stop.

Now think of a tractor tire perpendicular to that curb. The curb is WAY at the bottom, and the tire would roll over the curb like it's barely there.

[Irulan]

second stay away from kids bikes. There are plenty of small frame options out there for petite/tiny women. If your lbs doesn't understand this, find another one. They even make 29"ers for tiny frames.

[goldfinch]

I'd say stay away from the 24 inch wheels unless you are really good at front wheel lifts. The larger the wheel circumference, the higher obstacle you can "roll over" rather than have to lift the wheel and place it on top.

For illustration purposes, think of a kids bike tire perpendicular to a curb. See where the curb hits the tire? like halfway up! It's not going to roll over that. It's going to smack into it and stop.

Now think of a tractor tire perpendicular to that curb. The curb is WAY at the bottom, and the tire would roll over the curb like it's barely there.

I am taking this to heart. I also thought about a Terry but the mountain bikes in my size have 24 inch wheels.