Cutting Steer Tube down

Forum guidelines BT super discount
General Discussion Triathlon Talk » Cutting Steer Tube down Rss Feed  
Moderators: k9car363, alicefoeller Reply
2011-01-22 1:08 PM

User image

Master
1547
100050025
Subject: Cutting Steer Tube down
OK, the new bike is built, the fit is dialed in.  Turns out I will need no spacers so now there is a lot of steer tube sticking up (like 3.5") so I need to cut it down.  I would like to do this with out removing the fork...I'm thinking I can just remove the stem/bars to get access.  I've read on the net and it looks like slap some tape on there and go to town cutting with a hacksaw.

My concerns:

Can I do it this way or do I have to break down the bike (requiring new cable routing when I just did this).  I didn't see anything about cutting with bike built up.

Also, how much room should I leave above the top of the stem to allow for the cap? 

My last concern, and a little less of one...but, this is an expensive bike that should have aprox $3000 resale in the next year or so how much am I affecting the value by cutting down the tube?  I can't leave it the way it is, but I also don;t want to ruin the re-saleability.

2011-01-22 1:18 PM
in reply to: #3315264

User image

Extreme Veteran
845
50010010010025
Subject: RE: Cutting Steer Tube down
I think you could do it the way you described if you support the frame/fork.
You could potentially affect the resale by cutting it (who wouldn't want they option when they buy a bike?) but a new fork will solve that problem (if it exists) for the new owner.
Edit: I think about 5mm is good for room under the cap.

Edited by FuryUs 2011-01-22 1:19 PM
2011-01-22 1:25 PM
in reply to: #3315264

User image

Extreme Veteran
635
50010025
Georgia
Subject: RE: Cutting Steer Tube down
Hacksaws don't make a very nice cut, you'll need to clean it up a bit afterwards. Tubing cutters work nicely, deburring may still be required, but shouldn't take long.
2011-01-22 1:37 PM
in reply to: #3315264

User image

New user
112
100
Breckenridge
Subject: RE: Cutting Steer Tube down
Cut my carbon steerer with a hacksaw and a hose clamp as a guide. On the bike should be fine, measure twice cut once as the say.
2011-01-22 6:56 PM
in reply to: #3315264

User image

Champion
10668
500050005001002525
Tacoma, Washington
Subject: RE: Cutting Steer Tube down
For an aluminum steerer, a pipe cutter works fine, but you'll still want to clean up the burrs with a flat file afterwards. For a carbon steerer, use a saw guide (pipe clamps work "okay" for this) and a hacksaw. Make sure you vacuum up all the dist from cutting the carbon, though. And clean up the cut with sandpaper.

My recommendation: As for height -- if you're concerned about resale, then leave two spacers above the stem, and have about 2-3mm from the top of the top spacer to the steerer tube to allow for headset settling and making sure you can tension the bearings properly.
2011-01-22 7:30 PM
in reply to: #3315264

User image

Champion
7595
50002000500252525
Columbia, South Carolina
Subject: RE: Cutting Steer Tube down
If I were doing it this way, I'd set it up with the vacuum running WHILE you are cutting to avoid getting crap (bits of carbon) in places you don't want it.  Just have someone hold the vacuum right next to where you are cutting.

2011-01-22 8:05 PM
in reply to: #3315264

User image

Veteran
721
500100100
Naptown, IN
Subject: RE: Cutting Steer Tube down
Another option is to remove the front brake from the fork (leave the brake cable attached to the brake caliper).   Pull out the fork, cut the steerer, clean up the steerer tube, put fork back into frame and re-attach the brake caliper.
2011-01-23 9:31 AM
in reply to: #3315264

User image

Davenport, IA
Subject: RE: Cutting Steer Tube down
Is your steerer carbon or aluminum?  Carbon takes a special blade.
2011-01-23 10:40 AM
in reply to: #3315264

User image

Veteran
265
1001002525
Boston
Subject: RE: Cutting Steer Tube down
sax - 2011-01-22 2:08 PM

My last concern, and a little less of one...but, this is an expensive bike that should have aprox $3000 resale in the next year or so how much am I affecting the value by cutting down the tube?  I can't leave it the way it is, but I also don;t want to ruin the re-saleability.



If you cut down the tube, you will affect it's resale, much like cutting down a nice seatpost.  The amount it decreases will be entirely based on the buyer, since if you find somebody that want's/needs the spacers but has nowhere to put them, they need a new fork.  Just take that into consideration when cutting it.  If resale is still a concern, just figure either throwing in a new fork or discounting the bike the cost of a fork just in case, but otherwise go to town!
2011-01-23 9:46 PM
in reply to: #3315264

User image

Pro
5892
5000500100100100252525
, New Hampshire
Subject: RE: Cutting Steer Tube down
It's not that difficult to do... carbon just requires a fine tooth hacksaw blade, and no matter what, I would use a good guide (Park Tool make an excellent guide).

Just keep in mind that if you miss a measurement, you can potentially scrap your fork since you're not having any spacers at all... most LBS' won't charge much at all for a job like this and if something goes wrong, it's on their dime... could be the best $20-30 you ever spent...
2011-01-24 7:38 AM
in reply to: #3317188

User image

Master
2356
20001001001002525
Fenton, MI
Subject: RE: Cutting Steer Tube down
audiojan - 2011-01-23 10:46 PM It's not that difficult to do... carbon just requires a fine tooth hacksaw blade, and no matter what, I would use a good guide (Park Tool make an excellent guide). Just keep in mind that if you miss a measurement, you can potentially scrap your fork since you're not having any spacers at all...


I agree with this.  Also, if you don't cut it straight, you will have problems with the top cap sitting square.  Where is the starnut located?  Will you need to reinstall?

Personally, I always cut my head tubes at the max recommended length and stick with it.  Even if I would ride with the stem at the bottom of the tube, I have the extra space to attach my bento box.   

Using a guide (for carbon), wrapping with some masking tape to reduce splintering and dust, and using a fine tooth hack saw is an acceptable way of doing though.  I use a small shopvac to catch the dust though, while wearing a dust mask and safety glasses.   

2011-01-24 8:44 AM
in reply to: #3317525

User image

Champion
10668
500050005001002525
Tacoma, Washington
Subject: RE: Cutting Steer Tube down
matt3liv - 2011-01-24 5:38 AM
audiojan - 2011-01-23 10:46 PM It's not that difficult to do... carbon just requires a fine tooth hacksaw blade, and no matter what, I would use a good guide (Park Tool make an excellent guide). Just keep in mind that if you miss a measurement, you can potentially scrap your fork since you're not having any spacers at all...


I agree with this.  Also, if you don't cut it straight, you will have problems with the top cap sitting square.  Where is the starnut located?  Will you need to reinstall?

Personally, I always cut my head tubes at the max recommended length and stick with it.  Even if I would ride with the stem at the bottom of the tube, I have the extra space to attach my bento box.   

Using a guide (for carbon), wrapping with some masking tape to reduce splintering and dust, and using a fine tooth hack saw is an acceptable way of doing though.  I use a small shopvac to catch the dust though, while wearing a dust mask and safety glasses.   


The top cap shouldn't be up against the top of the steerer tube, it should be against either spacers or the stem clamp.
2011-01-24 8:50 AM
in reply to: #3317701

User image

Master
2356
20001001001002525
Fenton, MI
Subject: RE: Cutting Steer Tube down
briderdt - 2011-01-24 9:44 AM
matt3liv - 2011-01-24 5:38 AM
audiojan - 2011-01-23 10:46 PM It's not that difficult to do... carbon just requires a fine tooth hacksaw blade, and no matter what, I would use a good guide (Park Tool make an excellent guide). Just keep in mind that if you miss a measurement, you can potentially scrap your fork since you're not having any spacers at all...


I agree with this.  Also, if you don't cut it straight, you will have problems with the top cap sitting square.  Where is the starnut located?  Will you need to reinstall?

Personally, I always cut my head tubes at the max recommended length and stick with it.  Even if I would ride with the stem at the bottom of the tube, I have the extra space to attach my bento box.   

Using a guide (for carbon), wrapping with some masking tape to reduce splintering and dust, and using a fine tooth hack saw is an acceptable way of doing though.  I use a small shopvac to catch the dust though, while wearing a dust mask and safety glasses.   


The top cap shouldn't be up against the top of the steerer tube, it should be against either spacers or the stem clamp.


Yup, you are correct.  I was thinking of a more extreme "not straight", meaning less straight than the depth of the spacer.  Thanks for clarifying. 
New Thread
General Discussion Triathlon Talk » Cutting Steer Tube down Rss Feed