too stiff? umm, the forks i mean

[facio57]

hi everybody, i just changed my forks to progressives with 15wt fork oil and no spacers.  problem is the bike feels really stiff.  i mean feels like the wheel is absorbing all the shocks, i can't compress the front forks even a little when pushing down as hard as i can.  i just wanted some reassurance that this is normal.  is it?  too much oil maybe?  i measured 5.5" with forks fully compressed but now i am second guessing myself.  any ideas?

~facio

ps: i will now gladly help anyone in the 951/909 area to do fork seals! 

[Bluebellylint]

No that's not normal the shocks should compress. Too much oil can hydraulically lock the shocks so you should check the levels again.

[facio57]

i took out some oil and sure enough that was the culprit! strange though, i was sure i measured 5.5" with forks compressed and all that business ... oh well, works now, sayonara suckers! 

[pantablo]

lost the stiffy, eh?

[Blueknyt]

5.5" from the top,compressed WITH springs installed.  super basic idea on shocks, oil passes from oneside of the tube to the other through a valve that allows only so much oil to pass at one time given temp and viscosity(5w easy 20w hard.  now as the oil flows into the top tube (forks compressing) the oil is squeezing the air inside kinda like a piston does. pressure goes up and kinda pushes back on the oil.  now, liquids dont compress and if there is too much oil in the forks, it doesnt take much to compress what little air is left this makes a very hard ride.  for smaller sized shocks with large loads, you up the pressure of the air or use a gas like nitrogen.  this is very common on cars and trucks and better shocks on bikes.  its also why one doesnt cut shocks off of a car or truck with a torch, you cut the bolts. 

Ofcourse there is a fair bit more to shocks but this is just to give you an idea on how they work. seems to beat the underpants Gnome theory anyway.