sloping top tube vs. straight leveled tube
 

is there any difference? cuz i see some bike from specialized that has a sloping top tube and other bike manufactures has a straight tube. what's the difference and benefit of each? does it really make a big difference?

Don't own a compact (mine's traditional), but have talked with a number of friends who have - one being the owner of an LBS. I believe there are several differences;

• compact frames have a smaller triangle, which some claim improves handling, requires less material for greater stiffness and lighter weight
• compact frames are a good fit for many shorter riders because they increase the standover clearance and give them more adjustability than traditional frames
• because of the increased adjustability, stores don't have to stock/offer as many frame sizes (usually s, m, l)

Other differences were mentioned, but these are the ones that made some sense to me.

However, fit is still the most important thing for a road bike. The fact that compact fit relies more on the LBS to adjust seat fore/aft, height of both seat and stem to make it fit you (given that the compact frame is supposed to cover a range of traditional frame sizes) makes it even more critical to be dealing with a shop that knows what the heck they're doing.

Good luck!

cool.. so in that case the ones with a leveled top tube is the traditional frame and the one like specialized is the compact?

Yep. Don't know specifically what models you were looking at, but the general statement is true.

I'd say that's starting to become a pretty moot point these days. A lot of the sloping frames come in just as many sizes as their traditional counterparts. Even Giant, which I think most people are referring to when they talk about limited sizes now offer XS, S, M, M-L, L, XL. So, within those 6 sizes I think most people will be able to fit.

For some like me, you can get a long effective top-tube length with a stand-over height that's not too big for my "cycle" inseam length. For example, my new compact frame has a 2" shorter stand over height with the same effective top-tube length as my old bike. Now the pitch of my voice doesn't change when I put both feet on the ground.

Al

sweet... ok that makes sense then.

I know what you mean, but was just a general statement that, although there are certainly exceptions, is still pretty true. Almost depends on what price range you're looking at, because there are still many mid-high end traditional frame mfgrs. that offer 7-10 different cm sizing, plus some occasional women's sizes of same model. So even if you're only talking 2 different frames sizes in each model that you don't have to carry vs. traditional, still translates to a fair bit of inventory across a product line...

Adios :)

Steel rider has hit the nail on the head. Compact or slope top tube frames are a
great boon for manufacturers and bike shop owners because they reduce the number
of frame sizes that have to be made and stocked. Best case, tossing out people
under 60" tall or over 75" as customers you can get by with 4 frame sizes. Much nicer
than 2cm increments from 50 to 61cm. From the LBS point of view, it is hard to sell
a bike that is 3d away in a warehouse and if you get it shipped in and the customer
goes elsewhere you are stuck for awhile any way. A couple of round trips like that
will chew up a big chunk of profit. The slope top tube is derived from the hard tail
ATB frame and solves a lot of problems. Steve

that being said... I prefer traditional geometry! :D

I second that!

Same here. Compelling arguments for compacts aside, they look wrong and feel wrong. Creepy even. Against nature. I test rode a bunch of new bikes recently - Lemond, Felt, Giant and Trek, etc. Didn't like any of them besides the Trek w/traditional geometry. Not sure why, but there it is.

Just thought I'd chime in with my 2 cents. I have short legs in relation to the length of my torso. So for me I need a compact frame to get comfortable top tube and stand over in the same bike. It did take me a while to get over the way they looked tough. But after a few rides I forgot about that.

I found this quote here: http://www.bikes.com/main.cfm?l=en&p=02_101&CID=14

With BMX and trials bikes the sloping tube allows the seat to be very low for tricks and stuff. Obviously you can't do tricks with a long seatpost but supposedly the slope makes emergency dismount a little better?

Here's a nice custom built expedition touring bike with the slope. The seat is closer to the ground than on a regular MTB because of the low BB.

http://ic2.pbase.com/g4/85/557985/2/...9.80RcYJfe.jpg

There are also a slew of semi compact frames.

I have a 50cm semi compact frame and have no problems fitting 2 24oz Polar Bottles.

That depends, some have more slope than others. If you get a small frame with a steep stope then I doubt the you may be able to fit the 24oz bottle on the seat-tube compared to a zero slope.

You can also get a side-loading bottle cage.

Although I have yet to see it, I ordered a 40 cm center to top of top tube (yes, forty cm) frameset. I have ridden as large as a 52 cm to get some semblance of length in my bikes (currently 53.5 seat tube @ 74 degrees), but my seat is low enough that I can't clamp the seatpost in a traditional, now old-fashioned Park stand.

My new bike will be a 40 cm ST x 56.5 cm @ 75.5 deg TT, and yes, it'll slope like mad.

pic in this post:
http://sprinterdellacasa.blogspot.co...ltrasound.html

On my "test" 40 cm bike, a size S Giant TCR (40 c-t of top tube, 44 c-t of seat tube), I've used two large bottles in two normal cages (Specialized) without problems. Only thing is when I put something under the top tube, like a pump.

On an XS Giant I could see the seat tube bottle cage as having limited room.

cdr