Carbon Steerer Lengths

[gkamieneski]

I have been looking at these new carbon frames with tapered carbon head tubes and steerers. Often these bicycles are shown with quite a bit of steerer below the stem taken up by spacers.

For me, I need 9cm of drop between the top of the nose of the saddle and the bars. The last carbon fork I had, had an alloy steerer and I cut it to size after deploying a conical shaped carbon spacer to get the bars to the right height. Are these current models, particularly those delivered through mail-order, coming without their steerers cut and with variable spacers to move the stem up and down. It used to be suggested that you leave enough room when cutting a carbon steerer to be able to place a spacer on top of the stem before pre-loading with the star nut cap.

On the other hand, for frames purchased at the LBS, is the LBS cutting the steerer and using the appropriate spacers to get the rider the correct fit?

 

[oldbobcat]

Originally Posted by gkamieneski
On the other hand, for frames purchased at the LBS, is the LBS cutting the steerer and using the appropriate spacers to get the rider the correct fit?

If the customer requests it, yes. More often, though, we have to explain that the only way to get the handlebar even higher than its already ridiculously high state is to buy a riser stem.

 

[CAMPYBOB]

Quote by gk:
" It used to be suggested that you leave enough room when cutting a carbon steerer to be able to place a spacer on top of the stem before pre-loading with the star nut cap."

Star nuts are not to be used with carbon steerers. Compressor plugs/expanding plugs with carbon. Star nuts with aluminum and steel.

Some stem and/or frame and fork manufacturers require at least a 5 MM spacer below the stem. Some do not. Some require a spacer above the stem. Some do not. I like the stem as close to the headset as possible and if one is buying a bike to fit the rider this is usually easily accomplished. I just bought a frame that required me to delete the 15 MM tall conical headset top cap and replace it with an 8 MM 'flat cap' to get my fit.

I've seen pro's delete the entire top cap. That also deletes a headset warranty, possible the frame/fork warranty, but getting low and aero matters very much to racers saddled by contract to a certain frame geometry.

Some frame and fork manufacturers spec out a 25 MM max. of spacers below the stem and some go with a 40 MM max.

Many riders actually want the spacers there. As OBC said, some will go to great length and use weird and perhaps barely safe devices achieve even less drop from saddle to bars.

Some buyers prefer their steerer tubes chopped with maybe a 10 MM hedge left on the top of the stem. Some do not want any excess steerer left. Reasons for not chopping to the low limit include future re-sale value, changing fit due to injury or growth or bike use and just to suit current fashions. I've seen guys leave steerer sticking out to provide mounting for electronic toys. Buyer's choice.

 

[oldbobcat]

Originally Posted by CAMPYBOB

Many riders actually want the spacers there. As OBC said, some will go to great length and use weird and perhaps barely safe devices achieve even less drop from saddle to bars.

In many cases, that would be negative drop, or rise.

Thanks for catching the star nut fallacy, bob.

 

[CAMPYBOB]

Yeah. Some guys (read: old farts with bad backs and young clueless dudes with money) will buy the 14-pound road racer for the status and image projected by the latest TDF winner and then set it up like an Electra. Different strokes and all that.