Carbon Fork Question

I just got a new carbon fork and have a question. It’s an Alpha Q CS20 which has the insert. Per the specs on the fork, I can have a max of 80mm of steerer above the headset or a max of 40mm of spacers which assumes the stem has a stack of less of 40mm or less. My existing fork only has enough steerer for a 5mm spacer between the headset and stem which my shoulders and back tell me is a bit too short. The steerer on the new fork needs to be cut and I don’t want to fuck around overmuch trying to figure out what the perfect fit would be. I need the bars to be higher, but I’m not sure how much higher. I also know that I need a bit less reach, which will come with more steerer anyway.

I’m guessing that the best course of action is to cut the fork such that I have 40mm of spacer which will bring the bars up a little over an inch. I’m already using a +17 degree stem to get the bars up as much as I can. That would likely cause the bars to be higher than I like. I’m assuming at that point that I can use a +/-6 degree stem to dial in a position that I like. Worst case scenario is that I have to lower the stem and put a spacer on top giving me a sternum punch or I can remove up to 2cm additional after gluing in the insert.

I’m looking for opinions and reassurance here. I think I’ll like having the bars higher up by about an inch with a more normal stem. I doubt that I’ll really ever want them to be that much lower as I’m getting a bit old.

I’d much rather have a sternum punch than a too short steer tube. I’ve been riding my bike for 8 months and i’m still adjusting my stem. I’m really happy i didn’t have it cut earlier.

Sounds like you know what you’re doing. (Cut and leave the max amount recommended, dial from there.)

keep your current stem for now and shuffle spacers above and below it to dial it in. Then figure out what new stem you want and cut appropriately for that.

You don’t have to use the glue in insert until you have figured out exactly how tall you want it. Just go to your LBS and get a expanding star nut so you can take it out and replace it.

i’m looking at replacing my bent stock kilo fork

perhaps with this older kestrel carbon fork, made for litespeed

$50 bux. the guy at the shop was talking crown races, 26.4 (the size on the litespeed fork) vs 27.0


is the cane creek that comes with the stock kilo tt 26.4 or 27.0, anyone know? or should i replace/upgrade headset as i get a new fork?

(this is also in the “worth it” thread, so, um worth it?)

Too late. Glued insert is glued. The fork is awesome. A little less “solid” with the longer steer tube, but the fork is quite a bit stiffer than the stock carbon fork. 45+mph descents today and rather than feeling sketchy about it, I felt like I could go a bit faster.

Cane Creek and most other headsets have a 26.4 crown race. The Kilo and a lot of the other BD stuff is weird in that it uses JIS. I wouldn’t hesitate to cut down a 27.0 crown race to 26.4. So many more options.