Frame size, geometry

[Martinriggs]

Hello, I’m looking at buying a f500 with head shock. The frame size is listed as 17.5. I’m 5-11 with a 30inch inseam. Is this a good size for me or potentially too small? I know frame size listing can vary between manufacturers. Is cannondale known for sizing big? Small? Or accurate?

 

[black lightning 1987]

First step will be to figure out exactly what year and size the frame is, then look at the geometry chart in the catalog. F series frames were generally sized S, M, L, and XL. Some years had a size decal on the seat tube, some were stamped on the underside of the BB shell. I'm looking at the 1997 catalog right now. That year the S and M frames both had a seat tube measuring 17" from center of BB spindle to top of seat tube. L measured 19.5" and XL 21.4".

 

[Martinriggs]

First step will be to figure out exactly what year and size the frame is, then look at the geometry chart in the catalog. F series frames were generally sized S, M, L, and XL. Some years had a size decal on the seat tube, some were stamped on the underside of the BB shell. I'm looking at the 1997 catalog right now. That year the S and M frames both had a seat tube measuring 17" from center of BB spindle to top of seat tube. L measured 19.5" and XL 21.4".

Thanks for the info. That definitely helps. The last time I was fitted for a Mtn bike, I was told I should be on a frame 17.5 to 18.5. I’ve been away from cycling/fitness for awhile. Trying to get back into it.

 

[black lightning 1987]

The problem is that the amount of top tube slope can vary greatly from one frame to another, so seat tube length is not a very good indicator of how a frame will fit.

I would try to get a feel for what you like in terms of top tube length and saddle to bar height variation. If you don't have a bike now that you are comfortable on there are other ways to figure it out. Some shops will have adjustable "size cycles" that will allow you to quickly adjust angles and tube lengths. I have a Serotta model, Waterford makes one, and I'm sure there are plenty of others. You will have to pay for a fitting but it's a good way to get the right size without trial and error. Another option would be to borrow or rent something and spend some time on it.

 

[Martinriggs]

The problem is that the amount of top tube slope can vary greatly from one frame to another, so seat tube length is not a very good indicator of how a frame will fit.

I would try to get a feel for what you like in terms of top tube length and saddle to bar height variation. If you don't have a bike now that you are comfortable on there are other ways to figure it out. Some shops will have adjustable "size cycles" that will allow you to quickly adjust angles and tube lengths. I have a Serotta model, Waterford makes one, and I'm sure there are plenty of others. You will have to pay for a fitting but it's a good way to get the right size without trial and error. Another option would be to borrow or rent something and spend some time on it.

I’ll check it out. Also, how easy, difficult, expensive is it to repair or rebuild a first generation cannondale head shock?

 

[black lightning 1987]

Check in with Craig here:

https://www.mendoncyclesmith.com/