Singlespeed & Fixed Gear - Cutting fork down

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




View Full Version : Cutting fork down


ddddeuces
08-19-09, 12:38 PM
I just bought a 2009 Motobecane Jury frame and it comes with an uncut fork. I know how to measure for where I need to cut, but I don't want to bring it into the LBS. I want to build this bike myself. Does anyone have any tips for cutting? I also don't want to shell out 40 bucks on a saw guide that I'm only going to use once. Has anyone hand cut a fork before? Any tips? Thanks.


CliftonGK1
08-19-09, 12:40 PM
Go to the hardware store, get a pipe cutter and do it properly.

j3ffr3y
08-19-09, 12:47 PM
PIPECUTTER
inb4 hacksaw


ddddeuces
08-19-09, 12:52 PM
ah, good idea. i totally forgot that those exist. i was thinking hacksaw. thanks guys.

Zachee
08-19-09, 12:54 PM
PIPECUTTER
inb4 hacksaw

Hacksaw, metal sander.

Don't be a *****, get the job done right (wrong). Man up.

iFixed
08-19-09, 12:58 PM
I'm all for building the bike all yourself, but your lbs will charge you $10 to do this. In my mind not worth a DIY. If you don't already have a hacksaw or pipecutter, you're probably not skilled in using them(just assuming...I could be wrong here I realize) and risk jacking up the cut on your new fork.

CliftonGK1
08-19-09, 01:08 PM
If you don't already have a hacksaw or pipecutter, you're probably not skilled in using them(just assuming...I could be wrong here I realize) and risk jacking up the cut on your new fork.

How tough is it to use a pipe cutter?

1 - Open clamp screw
2 - Insert pipe
3 - Tighten clamp screw
4 - Rotate cutter
5 - Repeat 3 & 4 until pipe is severed

Mattpatt
08-19-09, 01:29 PM
How tough is it to use a pipe cutter incorrectly?

1 - Open clamp screw
2 - Insert pipe
3 - Tighten clamp screw too tight
4 - Rotate cutter
5 - Repeat 3 & 4 until pipe is severed and oval shaped.

Fix'd

MIN
08-19-09, 01:48 PM
you can use a spare stem and spacers as a cutting guide. use a new hacksaw blade.

Retro Grouch
08-19-09, 01:55 PM
Go to the hardware store, get a pipe cutter and do it properly.

Go to the hardware store. Get a screw-type hose clamp to use as a saw guide. Do it with a hack saw - properly.

Aged Bike Fixer
08-19-09, 02:11 PM
Go to the hardware store. Get a screw-type hose clamp to use as a saw guide. Do it with a hack saw - properly.

+1

A hacksaw works just fine and is not hard to make a straight cut--even without a guide. It's fairly easy to keep the blade on track if you watch your progress.

dougland89
08-19-09, 02:14 PM
if you use a hacksaw you're going to need a file, and time and patience.

robotkiller
08-19-09, 02:22 PM
Using a decent pipe cutter and slowly increasing the tension has never given me a problem.

dropspace
08-19-09, 02:33 PM
if you are ovalizing a steertube with a pipecutter you are trying too hard. it takes about 5 minutes to get through it going slowly. sand down the edges when you cut through and you are done. hacksaw works too.

I think we should get into a flamewar about which way is better though.

wearyourtruth
08-19-09, 02:40 PM
maybe i just have a steadier hand then others, but i've used a hacksaw many times to cut down steertubes. i use a piece of tape to mark off my cut and then go at it. this is, of course, assuming that we are talking about a threadless fork/headset. provided we are, there is room for error, as the top of the steer tube should never come flush with top of the stem, it should be a couple mm below it... otherwise, the top cap is compressing against the steertube and not the stem.

that said, you have room for your cut to be a *little* wobbly. as long as it's within 1-2 mm off center, and one side of it doesn't stick up above the stem, it will be fine. is it perfect? no. does it function EXACTLY the same? yes. with the top cap on will anyone be able to tell? no.

passerby
08-19-09, 04:11 PM
its really easy actually (you will need some patience and strong arms though). my friend has cut three forks with a pipecutter (no guide) perfectly. just make sure to cut a little lower than the top of the stem in order for the top cap to press against the actual stem.

edit: oops just read the other posts and theyr the same as mine. sorry for the repetitiveness

na975
08-19-09, 04:41 PM
a pipe cutter will create a mushroomed finish due to the cutting wheel being taperd, use a hacky saw.

j3ffr3y
08-19-09, 04:48 PM
a pipe cutter will create a mushroomed finish due to the cutting wheel being taperd, use a hacky saw.

that's why you fill the empty middle with a block or something, or file out when finished. Hack saw will not be terrible, but pipe cutter is easier to make a good cut.

Xgecko
08-19-09, 04:55 PM
I think we should get into a flamewar about which way is better though.


Pipe cutter is easier to do correctly but you still have to clean the inside of the pipe or your star nut won't fit correctly, hacksaw will give you a cleaner cut but it's really easy to **** up your fork if you are not "comfortable" with tools........I've done both I prefer pipe cutter for AL and a hacksaw for steel....

Retro Grouch
08-19-09, 06:21 PM
Pipe cutter is easier to do correctly but you still have to clean the inside of the pipe or your star nut won't fit correctly, hacksaw will give you a cleaner cut but it's really easy to **** up your fork if you are not "comfortable" with tools........I've done both I prefer pipe cutter for AL and a hacksaw for steel....

Actually, my thinking was based on an assumption that the OP was likely to already own a hack saw but would have to buy a pipe cutter. If that's the case, buying an 89 cent hose clamp to provide him with something square to guide his cutting is a pretty cheap solution.

Whether I personally used a pipe cutter or a hack saw, I'd still take the time to deburr the cut.

MPLSdunk
08-19-09, 06:28 PM
pipecutter+file

ADSR
08-20-09, 01:53 AM
Pay your LBS and avoid a confusing thread that contradicts itself with each post. Just have them do it, so if it gets messed up they owe you a fork.

Retro Grouch
08-20-09, 02:22 AM
Pay your LBS and avoid a confusing thread that contradicts itself with each post. Just have them do it, so if it gets messed up they owe you a fork.

You have a point.

The only bike mechanics I know who won't admit to having cut at least one fork too short are the guys who lie about everything else too.

JohnDThompson
08-20-09, 07:18 AM
I'm all for building the bike all yourself, but your lbs will charge you $10 to do this. In my mind not worth a DIY. If you don't already have a hacksaw or pipecutter, you're probably not skilled in using them(just assuming...I could be wrong here I realize) and risk jacking up the cut on your new fork.
+1
If the LBS screws it up, it's their problem, not yours.

ddddeuces
08-20-09, 08:21 AM
thanks guys. i will be bringing this to the lbs.
also fyi, i am plenty skilled with a hacksaw and i have also used pipe cutters before :]

Xgecko
08-20-09, 09:06 AM
honestly I'm not a pro mechanic just an occasionally paid skilled amateur but I have never cut a fork too short.....had to cut a few more than once but never too short.....measure a handfull of times cut once