bleeding forks, got a few questions

[ctdyno]

ok i have never bled my forks and havent changed the fluid, wondering how and how often the fluid should be changed and i keep getting mixed answers on this next oen, should i bleed the ai r out of the forks while they are unsprung and on a stand or under the bikes own weight
thanks

 

[mox69]

Only bleed the forks when the front wheel is off the gound.


As far as how often to change the oil. Most suspension shops recommend around 20 hours, for the MX racers. YMMV.

 

[ctdyno]

thanks
for some reason someone said do it on the ground which really doesnt make much sense to me at all, anyways thanks for the advice

 

[ctdyno]

ok well my dad is saying that the front forks might be gas charged and id blow the charge off, is this true? 1997 cr125

 

[jason33]

no- let the air out with the wheel on the ground---- if you dont the forks will be exstended farther than normal,and have air trapped in the tubes,let the bike stand with normal sag- with out pressure on the bike-(no one on the bike)

 

[ctdyno]

anyone?

 

[IndyMX]

The only gas in a 1997 CR125 Fork is AIR...

The rear shock is Nitrogen charged though, so don't bleed it off. That'd be bad.

 

[ctdyno]

haha well yea i kno the back is, but i can still bleed the front? my dad and his friends are saying you might ave to have a few pounds of pressure on the front even with air

 

[ctdyno]

***

 

[_JOE_]

You want to bleed off any trapped air. Do it off the ground. After you replace the screws and set it down the forks develop some air pressure. They are designed to work with this air in there. You can now explain to your Dad why your bike may be different than something he was used to. Get a service manual, and look it over good. You can learn alot about your bike works from that.

 

[ctdyno]

yea thanks, ive been meaning to get a service manual for a while just havent gotten around to it yet

 

[adam_co]

i wud get a shop to do it if i wer you, i tried to replace the seals on my kx80 and completely knackered it up and ended up buyin a used set of forks off my mate as he had a spare kx80 frame and the rest without the engine in

 

[_JOE_]

i wud get a shop to do it if i wer you, i tried to replace the seals on my kx80 and completely knackered it up and ended up buyin a used set of forks off my mate as he had a spare kx80 frame and the rest without the engine in

If you need to take your bike to the shop to have the air bled from the forks, you should consider a different hobby. If you can turn a screwdriver, you can bleed forks. Seals on the otherhand are most often better left to a professional.

 

[mox69]

Place your bike on the stand, so the front wheel is OFF THE GROUND. Unscrew the little screw in the top of the fork, wait 2 seconds, put screw back in. Repeat on other side. Place bike back on ground.

If you do this while the forks are compressed you will introduce a negative pressure into the forks. This isn't really good.


Forks are not air charged. Rear shock is not air charged.

 

[ctdyno]

my rear is nitrogen charged, but yea thanks for all the replies

 

[Billy Maze]

Allot of conflicting advice in this thread.
Scary.

 

[chiro972]

I'm looking right at my Yamaha yz250 service manual and it says to do it with the bike on a stand.