Ducati Sporting Club UK > DesmoDue Race Series > DesmoDue - General Questions and Chat > What's the cheapest way of making my standard Marzo forks harder?

[skidlids]

Fitted Ohlins springs meant for a Honda Firestorm (41mm dia. fork leg) in my early SS forks circa 1996.
When I first put up pics of my bike with the 916 fairing in my DD diary, questions were asked about the fairing hitting the mudgaurd.
With the single rate Ohlins springs it NEVER did

[Jools]

So if the bike vibrates when you brake are you sure the forks need to be stiffer? Could it be a warped disc? Or not enough rebound damping?

[couchcommando]

I'm running 9kg linear rate springs in mine with standard weight oil and standard oil amount, the difference was amazing for the price of a pair of springs.

[skidlids]

Originally Posted by Jools

So if the bike vibrates when you brake are you sure the forks need to be stiffer? Could it be a warped disc? Or not enough rebound damping?

My 750SSie has a lot of fork judder (vibration) all the time under braking and changing down gears unless I set the tickover to 1800rpm or above, then its no longer a problem.

[Gizmo]

thicker oil slows the compression damping down so it takes longer to get to bottom out but it still will bottom if the bump force is big/fast enough. a combination of thicker and more volume might help but it all depends how far out the springs are or whether its actually to much rebound packing the fork down ( the fork can't recover from one bump before it hits another so eventually it runs out of travel)

Preloading a spring with more washers won't make it harder, it'll increase the ride height but thats all. a spring moves a set amount for a set load, so its rated as say 10kg/mm it'll take 10kg to move it 1 mm and no matter how much you push it it down it'll always take the same 10kg to move that 1mm until the coils on the spring bind together. if you start with a higher ride height there is less chance you'll bottom it as the fork needs to move further. try and set sag up correctly and if possible swap the spring to a one which is correct.