Fork length and headtube stresses - experiences?

Toadie77 said:

Hello all,

This forum has been a big help for me working on my bike. I recently changed out my fork; the swap was easy and made a big difference. The only part that took some time was getting the star nut in the new fork tube, but that was my fault – live and learn – right?

Now my fork is 130mm travel and replaced a 80mm fork. I fox float allow you to adjust down to 100mm travel -- but why would I want to do that right?. Frame is an old specialized alum frame (hardtail). Now the extra 2 inches probably would void my frame warranty due to added stress of a taller fork (I’m not too concerned about the warranty at this point).

Has anyone ever actually seen a frame fail at the headtube due to a longer than manufacturer allowed fork? My guess s even if the frame “fails” it cracks, and does not simply shear off sending you tumbling over the handlebars. Any clarity on this would be appreciated.

My take on this is to ride my fork with the preload set very low – sag of about half the travel. This gets me close to the stock ride height, and allows the fork to drop into the bumps when riding. So I’m thinking that the added stress is pretty small, and my riding style is pretty tame compared to what most of you guys are doing.

The long term plan is to build up a frame and use the fork in the new build, but why not ride it now right?

Thanks for the help,
[font=Times New Roman][font=Verdana]Greg[/font][/font]

going from 80 to 130mm will change the handling alot, it probably wont climb as well as it did now. theres also the possibility of it failing but on a bike meant for a 80mm fork going to 130mm will generally screw up handling quite bad, also with having extra sag.. when your climbing a hill and the weight is off the front the fork will lift.