mattscq

So in all of Canyon's marketing material, probably for the sake of looking cool, all their bikes show a slammed stem with a flush top cap. I've finally dialed in my fit and I would like to clean up the 2 spacers above my stem. There seems to be a large contingent of people who recommend keeping 2-5mm above the stem, especially for carbon steerers. Does anybody have any experience with this? I would prefer to cut it flush. Ideas?

Thanks

Andrew R Stewart 

Some fork manufacturers require some steerer above the stem or warranties might be voided. I would most certainly NOT cut the steerer if only 2cm were above the slammed stem. What a way to cut away future options, what a way to reduce the resale value. All for a few grams of weight and some miss spent dream of looking like a sponsored pro. But it's your bike and your body so do as you will. Andy

mattscq

Oh no, there's more than 2mm above my stem, it's 2 spacers. A thought is also if you were to stack all the spacers in below the stem, the top cap would be flush anyway.

Andrew R Stewart 

I didn't say 2mm I said 2cm. BTW referring to a dimension with a non specific term like "spacer" can be cause of confusion. The reasons to place spacers below the stem is only that of fitting the rider's position, not to make the top of the stem flush. The reason to have a few mms of steerer above the stem is to reduce the carbon steerer's wanting to crack from the clamping pressure the stem applies. If you have found your fit and if that has some steerer above the stem and if that steerer is a carbon one then I think you should just add the needed spacers to make the top cap preload the headset properly and go ride the bike. Humans get so wrapped up in thinking about how they think others see them. I generally think about how my fellow riders are handling their bike and the changing situations during the ride then where their stems are. Andy

Eric F 

Depending on the design of the compression nut, it may provide support around the top of the steerer tube, which eliminates concerns about the connection loosening over time due to the tube getting crushed. Paying attention to the correct torque on the stem bolts is also critical. It's your bike. If you want to trim the steerer to suit your fit and appearance preferences, go for it. Just be aware of the future limitations it may have on fit adjustments for yourself and others. If you're going for a flush top cap, it's still best to leave the steerer as long as possible inside the stem (trim it only enough to get the top cap flush) to keep as much stem-steerer contact area as you can.

Crankycrank

I agree 100% with Andrew. Unless there is some sound reason for structural safety or you have 100mm of steerer above the stem then I see no reason to cut.

Iride01 

I never notice how much steerer tube and spacer are on top of some ones stem when I pass them. So I'd suggest you just not worry about it. Leaves you with options and I think a more saleable item when you decide to get rid of it. Forks are expensive so a savvy buyer will be looking at things like that.

I suppose if I were to sit in the living room with my bike in front of me, it might bug me aesthetically, but it doesn't. My bike is in the other room.

Litespud

I cut off my steerer ~2 mm below the stem - always planned to do it, because I hate the look of a "chimney". However, I rode the bike for ~1 year before I did it, so I was well and truly sure that the setup was right for me. I have a long expander plug in the steerer, the upper stem bolt is below the top of the cut steerer, I'm careful torquing everything, and I pull the top cap periodically to inspect the steerer for cracks or anything fishy. I'm not concerned about resale - riding around with a chimney that I'd hate just to convenience The Next Guy is like leaving the plastic on the sofa.
IIRC one poster here (DaveSSS, I think) installs a permanent "plug" by filling the top couple of inches with epoxy - one possible way to allay fears of compromising structural integrity with a flush-cut steerer

mattscq

It's funny that a lot of people think I'm doing this only because I care about what other people think but I know nobody cares. It's entirely for myself. I'm not concerned about the resale issue either. I'm not slamming it down unreasonably; I'm merely removing a couple cm to tidy up the top. I'm more interested in what people's opinions are regarding the structural issue. I can understand that it might be a concern if the stem doesn't grip the steerer entirely but if the steerer is flush with the top of the step, why would that be a possible weakpoint?

To complicate things, Canyon seems to have given me 2 answers: one is to leave 2mm above and one is that it's fine to be flush. Interestingly, all their imagery shows it flush.

Iride01 

Differences in the way different materials deal with stresses. Typically I see it recommended that carbon steerers be left a few millimeters above the top of the stem. In that case you'll have to have at least one small spacer unless your cap handles that. Steel steerers I usually will see the mfr says it's okay to cut them just shy of the top of the stem.

DaveSSS 

A zipp top cap allows 2mm of steerer above the stem with no spacers. Often called a bottle cap style.

blamester

I cut mine flush. No issues. Looks good. Suits me.
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