Hi there all

Is there any way of adjusting the fork pre load on a pro 09?

Thanks in advance

Brokeback

Red cap on the forks? If not, just the cap with the allen key hole in it, wind it in to add preload, out to reduce.

The right fork has a red cap on it but I cant see any allen key

Do you have to remove the cap to get at it?

Confused

Edited June 20, 200917 yr by brokeback

See the cap, it has a small hole in the top, yes? A large allen key fits into that slot... Then you tighten it up to add preload, or losen it to slacken off the pre-load!

If not, get us a pic and we'll try to help.

I cleaned the lens!!

Red cap on the forks? If not, just the cap with the allen key hole in it, wind it in to add preload, out to reduce.

The Marzocchi fork does not have an external preload. Rather than a compression/rebound cartridge in one side and a preload spring in the other leg, it has a dedicated compression cartridge on the left and a dedicated rebound cartridge on the right. That way they are independently tunable. With a single cartridge handling both compression and rebound, any change in oil viscosity will affect both rebound and compression the same way. With the cartridges in each fork, you can make viscosity changes independently for rebound or compression and the single stage damping will be much more effecient.

The preload is inside the fork leg and consists of a PVC collar that can be replaced with one longer or shorter to increase or decrease spring preload.

Jon

Not to challenge Jon, but the pre-load is adjustable be turning the large nut inside the red ring (the one with the R on it). Don't overdue it either way as you can damage the internal stop if it is forced.

Spencer

Ahhh, these things...

You cant adjust preload as such, but you can slow or speed up dampening and rebound seperately.

If you want to do preload you'll have to dismantle the forks, remove the plastic tube and make up an new one of the same diameter.

You can try screwing the large nut with the screws in it, a bit... not to far though, that will make a difference, if thats not to your liking just adjust the two screws, they make a huge difference to the feeling of the bike and you SHOULD be able to get it how you want!

my mate wants to soften the front end on his 2007 TXT pro 280. i understand that to reduce the preload he should reduce the length of the preload spacer. should this be done on both forks or just the preload left? many thanks

my mate wants to soften the front end on his 2007 TXT pro 280. i understand that to reduce the preload he should reduce the length of the preload spacer. should this be done on both forks or just the preload left? many thanks

Preload isn't really what determines the firmness of the fork,it determines ride height(Unless you have so much preload that you have zero sag)

Compression damping,oil level and viscosity control the stiffness of the fork. Sometimes too slow of a rebound setting will make a fork harsh in repetitive bumps.

Ahhh, these things...

You cant adjust preload as such, but you can slow or speed up dampening and rebound seperately.

If you want to do preload you'll have to dismantle the forks, remove the plastic tube and make up an new one of the same diameter.

You can try screwing the large nut with the screws in it, a bit... not to far though, that will make a difference, if thats not to your liking just adjust the two screws, they make a huge difference to the feeling of the bike and you SHOULD be able to get it how you want!

THIS IS INCORRECT!!!

On the forks pictured you CAN adjust the preload,just wind in the 22mm nut in the picture inside the red ring,it allows about an extra 5mm of preload.

Benz

thanks guys good info. glad to know there is a little adustment on the rebound side if required. however the front end appears to have been jacked right up. so will start by reducing the preload before changing spings or fork oil. do i reduce the spacer length on both sides?

Edited March 25, 201016 yr by jokerr

The 09 forks always felt too firm to me.

First ones had 7.5 w oil, changed that to 5wt - much better.

I head the some type of fork seals were causing friction, so I striped mine but couldn't feel this, but removed dust scraper spring to help.

Finally, cut 3mm off spacer tube & went to 2.5 w oil.

Feels like I've got there.....testing in France at Easter.

Jokerr.....I assume you're releasing the built up air via the bleed screws?

cheers motomerlin your the second person to mention this in the last 24hrs. i did not realise that this is most likely to be the problem and should save a lot of messing about. is it just a case of slackening screws and letting air out? many thanks.