picking the right kind of fork



10timesbetter

New Member
Oct 7, 2004
119
0
0
I know the difference between 1inch, and 1-1/8, threaded and non-threaded, so no questions with any of that stuff, but I have a cyclocross bike that I plan on switching over to a normal road bike, so first i've been looking around at new forks, but i've got a few questions,

right now, the steerer tube including the threads, is about 165mm long, when i look for a fork, and people say it's 180mm, with 40mm of threads, are they including the threads in the first measurement, or no? I'm just curious if i should be measuring from the bottom of the steerer tube up to the threads, or all the way up to the top of the tube. do threads need to be a specific lenth? if mine has 40mm now, and i found a fork with 50mm of threads, there's no reason that'd mess anything up is there? aside from a possible faster wear on the bearings?

my other option is to upgrade to a threadless fork, if I do that, how much longer should the threadless fork tube be than the one i've got now, and if i found one that's longer, is there any reason that I couldn't just take the hacksaw to it to make it longer? even one with a carbon steerer, or would that be a bad idea?

thanks for any help you guys can give me
 
It's probably easier for you to gives us the measurement of the head-tube on the frame.

I can't speak for all, but most people tend to include the whole steerer when they give you a steerer length.

The threads don't have to be a precise length; they just have to come down far enough to permit the headset to screw right down.
Strictly speeaking, it's best to have the expander on the head stem below the threads, so if the thread goes way down the steerer, you might have to have your bars too low.

If you have a threaded Shimano 'road' headset, the fork steerer has to be an absolute minimum of 35 to 37mm longer than the frame's headtube, but that's with no spacers, so 40 to 45mm longer (or even a little more) would be better. The unthreaded part of the steerer can be no longer than ~18mm longer than the headtube.
Having said all that, other headsets can vary in stack height.

My threadless Cane Creek S2, 1" headset has a stack height of about 27mm, and my stem is 40mm deep, so, without ANY spacers, the absolute minimum for me would be about 62mm (a threadless steerer should end just below the top of the stem).

This is just an example. It really depends what sort of threadless headset and stem you were to use.

Another thing you should consider is how high you want your handle bars.
 
I like to be leaned over so i usually like by bars as low as they'll go, my usual ride is an old schwinn world, and i think the fork tube is only about 145mm, and the stem is just right on the top of that, and about 120mm long. once i get back to school tomorrow i'll get the measurements on the bike I wanna get the forks for, I can't remember them off the top of my head, I'm almost positive the threaded fork tube is 165mm, and considering the steerer tube on the frame is longer than my bike now, i'm not gonna want any spacers or anything,
 
10timesbetter said:
think the fork tube is only about 145mm, ,

Is this the frame tube? When buying a fork, it's important that you give the exact measurement of the frame's headtube.

You can also hacksaw cro-mo (steel) as well as alu and carbon steerers, so cutting down is no problem.

What can be annoying for your bike shop though, is cutting more thread in a cro-mo steerer. They don't like doing it coz it's pain in the ass, and good cro-mo can blunt their very expensive tool :)
 
Well, Bordy, you haven't bagged my mechanical advice. Does this mean I got it all right, or couldn't you be bothered reading my long post? :D
 
alright, finally got to measure it, for the fork, the steerer tube is 175mm long total, and just 145mm from the base up to the threads, I did measure the headtube on the frame but I can't remember what it is, 135 maybe? I'm off to the bike shop now, which has a ton of parts around, i'm gonna see if I can find another fork there, if not i'll start checking around ebay. but thanks for the help, i'll see what i can find
 
ooh, and something else, i've seen forks on ebay that say they're made for an integrated headset, will they pretty much be the same thing, or can they not be used on a normal headset?
 
10timesbetter said:
ooh, and something else, i've seen forks on ebay that say they're made for an integrated headset, will they pretty much be the same thing, or can they not be used on a normal headset?
They work.They just look goofy.
 
10timesbetter said:
alright, finally got to measure it, for the fork, the steerer tube is 175mm long total, and just 145mm from the base up to the threads, I did measure the headtube on the frame but I can't remember what it is, 135 maybe? I'm off to the bike shop now, which has a ton of parts around, i'm gonna see if I can find another fork there, if not i'll start checking around ebay. but thanks for the help, i'll see what i can find
Your headtube length is the most important part,second most important part is do you want threaded of threadless.Your cross frame was also built around a specific fork rake and crown to dropout distance. There is more to it than just sticking a road fork in there and I fail to see the real point anyway.
 
well i haven't ridden enough to know a ton about what kind of rake i like and all that, right now i've got 3 bikes, and they're all different sizes and ages, so I'm not looking to get too picky, the same with the threaded or threadless, whichever I can find first i'll put on my bike, I'm doing mroe than just switching the fork, but that's the point i'm at right now, but it has the cyclocross fork, which is about 4 inches taller than it needs to be, and the bars are rediculously wide, and it's awkward for just riding around the road, so the main things now are lowering the front end, and making it a little skinnier, the frame i have, i've also seen on road bikes and timetrial bikes, so i'm not sure that they would've made a bunch of completely different bikes, or if they just change a few of the parts and sell it different ways,
 
10timesbetter said:
well i haven't ridden enough to know a ton about what kind of rake i like and all that, right now i've got 3 bikes, and they're all different sizes and ages, so I'm not looking to get too picky, the same with the threaded or threadless, whichever I can find first i'll put on my bike, I'm doing mroe than just switching the fork, but that's the point i'm at right now, but it has the cyclocross fork, which is about 4 inches taller than it needs to be, and the bars are rediculously wide, and it's awkward for just riding around the road, so the main things now are lowering the front end, and making it a little skinnier, the frame i have, i've also seen on road bikes and timetrial bikes, so i'm not sure that they would've made a bunch of completely different bikes, or if they just change a few of the parts and sell it different ways,
It's not about what kind or rake you 'like'. It's about what the frame was designed around. If it was designed around a fork with 40mm rake and you get one with 45 or 47,you may not LIKE the result. If you lower the front end,you will also hose the handling. You don't really have a clue,will probably pizz alot of money away and should just leave well enough alone. Although you might be able to handle installing a narrower bar, but doing that poorly could send you to the emergency room.
 
haha, the hospital? i know how to install handlebars, and i'm not gonna blow a ton of money on all of this, I already have a spare set of bars, so the only thing i really need to get the bike back together is the forks, and i'm just looking around ebay for those, which is why i have all the questions here, if i was blowing money on new ones i'd just take my bike to the shop and see which ones fit, but i'm just gonna find them on ebay, and if my life turns to **** because of it, as you're telling me it will, i'll just resell the forks, no big deal,
 
10timesbetter said:
haha, the hospital? i know how to install handlebars, and i'm not gonna blow a ton of money on all of this, I already have a spare set of bars, so the only thing i really need to get the bike back together is the forks, and i'm just looking around ebay for those, which is why i have all the questions here, if i was blowing money on new ones i'd just take my bike to the shop and see which ones fit, but i'm just gonna find them on ebay, and if my life turns to **** because of it, as you're telling me it will, i'll just resell the forks, no big deal,
By lowering the front of the bike you will be steepening the head angle. Depending on the rake of the new fork you will be reducing trail (caster on a car) or what keeps a shopping cart going straight. This will make the bike ride squirelly not to mention look stupid with a forward sloping top tube.
 
SDL said:
By lowering the front of the bike you will be steepening the head angle. Depending on the rake of the new fork you will be reducing trail (caster on a car) or what keeps a shopping cart going straight. This will make the bike ride squirelly not to mention look stupid with a forward sloping top tube.
He knows everything,and sometimes Darwinsim needs some help.