Cutting carbon steerer without removing fork?

luv2ride

Did a quick search before posting, as am sure I've read something on the exact same question recently, but couldn't find anything...so, forgive the repeat post...Would cutting the carbon steerer 'in situ', i.e. not removing first from the frame, be pure folly?

Happy with my position on my new bike, so now need to lop 30-40mm off the top of the steerer. However, the fork has internal routing for the the hydraulic brake hose for the disc brakes. I'd rather not start disconnecting hoses, bleeding and re-charging the hydraulic system if poss, so had considered simply removing the bars, spacers, stem and steerer bung, marking up the cut-line and "going in" with a carbon cutting blade, and guides made up of 2 x jubilee clips, or similar. Anyone tried this, or is it always better to drop the forks entirely from the frame to make the cut?

airborne_warrior

I cut my steerer tube with the forks still attached. Just laid the bike on its side and cut away.

meanredspider

I think you'd be OK provided you go steady and take care with the dust. Only you know how dexterous (or not) you are to perform these sorts of things. Take your time and get properly set up and comfortable and I think all will be OK. And, if it looks to be going wrong, stop.

imposter2.0

It's doable. A decent cutter guide (or an improvised old stem) is necessary if you want a straight line.

luv2ride

meanredspider wrote:

I think you'd be OK provided you go steady and take care with the dust. Only you know how dexterous (or not) you are to perform these sorts of things. Take your time and get properly set up and comfortable and I think all will be OK. And, if it looks to be going wrong, stop.

...im getting a cold sweat on just thinking about it, so exercising caution won't be an issue :oops: LBS quoted a tenner but I'm pretty sure they hadn't appreciated the through-fork hose routing, and associated faff, though may still talk to them first. Looking again I think I could drop the forks out, but wanted to avoid the daisy-chain effect of the hose still being connected to brifters/bars, swinging off the bike, with the hose still sitting through the fork. Cutting in situ seemed a "safer" option as long as I can stop the steerer moving too much in the headtube sans spacers and headset, etc. A soft wedge of some kind would probably do that if needed.

So, gloves (check), face mask (check), safety glasses (check), old Hoover (check), now just need to fabricate a guide and get a carbon blade/hacksaw - and maybe a dose of Dutch courage....im such a wuss :shock: !

meanredspider

IMO the tasks that you most dread are the easiest - it's the ones that you think are going to be easy are those that bite you in the butt. I never learn, for instance, that changing the rear exhaust box is ALWAYS a job to pay someone to do (and I'm happy to tackle just about any mechanical task).

Good luck

fat daddy

I have always cut my stems in situe ... it's no issue ... if anything it's easier as the stem keeps still with it being mounted in a bike

siddy1972

I've done it both ways. No problems with either option. Just go really slow and let the blade do the work. And careful not to slip and whack your top tube with the saw.

londoncommuter

That was my post on the same thing you spotted. Was no problem at all in the end, didn't even need any help to hold the bike. Just used a cutter guide as normal (not sure I'd fabricate one as you suggested!).

On cutter guides, they cost peanuts and, although you think you'll only use it once, I've now ended up cutting five carbon steerers and two aluminium. Maybe I buy too many bikes though.....

luv2ride

londoncommuter wrote:

That was my post on the same thing you spotted. Was no problem at all in the end, didn't even need any help to hold the bike. Just used a cutter guide as normal (not sure I'd fabricate one as you suggested!).

On cutter guides, they cost peanuts and, although you think you'll only use it once, I've now ended up cutting five carbon steerers and two aluminium. Maybe I buy too many bikes though.....

Cutting guide now ordered, along with a new hacksaw AND a carbon-specific blade. Depending on how I get on I will also be lopping bits off 2 x alu, and 3 x carbon, steerer tubes. As you say, will be useful to have (I hope).

Hopefully here for the weekend.

luv2ride

Mission complete. Saw guide and carbon-specific blade gave a nice clean cut though was slightly harder going than I expected. Also wasn't expecting quite so much dust, so grateful for gloves and face mask. Front end looks very neat now. May chop the steerer on the CX down later, very satisfying

pippi_langsamer-2

Luv2ride wrote:

meanredspider wrote:

So, gloves (check), face mask (check), safety glasses (check), old Hoover (check), now just need to fabricate a guide and get a carbon blade/hacksaw - and maybe a dose of Dutch courage....im such a wuss :shock: !

It's not alien spore! Yes- not good if you breathe it in, but just be sensible. I've cut lots of steerers in-situ, and never bothered with PPE. Old stem as a guide, fine tooth hacksaw and away ye saw! The amount of dust created from cutting a section that small is minimal anyway