General Cycling Discussion - Things to look out for......

when buying a used fork. JUst wondering what are the kinds of things you would look for.

Thomas

Use common sense. If you see a crack don't buy it. If it's bent don't buy it either. Don’t believe everything seller says, inspect it closely.. And so on and so forth. :beer:

Compare the length from where the axle sits to the crown of the fork. Any difference there from what you have will affect bike handling characteristics.

Steerer tube lenght.

Stack height, steerer tube height, stem height and a couple of spacers.

L8R

You didn't say what it's made of. If it's aluminum or carbon fiber, i wouldn't buy it. CF is untrustworthy even when new; with used aluminum you don't know how many fatigue cycles its been thru, & unlike steel, aluminum has only so many before it fails.

Steel most definitely has a fatigue life as well! However, the endurance limit of steel can be somewhat higher than aluminium, so the stress in a steel fork may be below that which will cause fatigue cracking. It is highly dependant on the grade and heat treatment of the aluminium or steel. A blanket statement that steel doesn't have a fatigue life is just not the case.

What are you gonna eat with it? :p :D:D
sorry.

I'm assuming that you know about rake, and exactly how much rake you need on the new fork? If not, don't continue until you do.

Hi Cirrus. We discussed this in the thread on frame materials. From what i know, steel will never fail as long as it's never stressed beyond its rated limit, whereas aluminum will eventually fail after a certain number of cycles.

In any case, i've never heard of a steel fork failing or even developing a crack short of traumatic impact, tho i'm sure someone will give me some examples.:->

Ebro38,

Yes, quite correct. If the stress in the steel is below the endurance limit it will "never" fail in fatigue. Exactly the same is true for aluminium. Steel "generally" has a higher endurance limit than aluminium.

I don't really know what the stress is in a bike frame, but I'm guessing that it's well below the endurance limit for steel, but may be slightly above the endurance limit for aluminium. Which is why you

may see fatigue failure in an aluminium frame compared with a steel frame.

when buying a used fork. JUst wondering what are the kinds of things you would look for

Make sure it comes with a matching knife.:roflmao:

CHEERS.

Mark