When replacing fork oil, do you strip the forks down completly?

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katana
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When replacing fork oil, do you strip the forks down completly?

Post by katana »

Hello all,

Another day and more stupid/pointless question to most but can you settle a discussion.

Am chnging the fork oil on Tequilapixie MK1 fazer, as a general refresh as it has been 10 years ;) So I was just going to undo the top nut a few turns, remove the forks from the bike and undo the top nut, remove the spring and the spacers then leave the forks to drain for a few days. Maybe a few squirts of brake cleaner or maybe some isoprpoyl alcohol to rinse out crap left over.

Should I undo the bottom damper bit? I'm not taking the forks apart so I'm not bothering. Some say that I should strip the forks down completly but on an oil change with no other adjustemnts. Should I take take them apart or not. Or am I over thinking this.
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Re: When replacing fork oil, do you strip the forks down completly?

Post by BBB »

I do what you're planning to, empty out the old oil and flush with brake cleaner a few times. Left the damper assembly in the zx6r, just the spring and spacers.
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Re: When replacing fork oil, do you strip the forks down completly?

Post by mangocrazy »

Does your Fazer have damper rod or cartridge forks? If they're damper rod, then what you describe should be fine. If they're cartridge forks then clearances/tolerances are much finer and ideally you'd want to strip and clean the internals thoroughly. After 10 years, the oil in any forks will be minging.

your call, really...
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Re: When replacing fork oil, do you strip the forks down completly?

Post by DefTrap »

I do, but only because it's generally pretty easy (and normally because my seals tend to go bad before the oil iyswim) and you get to see any other wearing parts up close while you're there. My only advice is to crack some bolts before you genuinely start to dismantle as this may give you an idea how tough the job might be. Typically the longer it has been since it was last dismantled, the more of a pig it will be.
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Re: When replacing fork oil, do you strip the forks down completly?

Post by Le_Fromage_Grande »

If it's damper rod (and it probably is) just empty the oil out and put some fresh in, quite a lot of forks have drain screws on the forks so you don't have to take them out. Cartridge forks are a bit of pain to get all the old oil out of, you need to pump the cartridge to get it to come out.
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Re: When replacing fork oil, do you strip the forks down completly?

Post by katana »

mangocrazy wrote: Mon Jan 08, 2024 12:30 pm Does your Fazer have damper rod or cartridge forks? If they're damper rod, then what you describe should be fine. If they're cartridge forks then clearances/tolerances are much finer and ideally you'd want to strip and clean the internals thoroughly. After 10 years, the oil in any forks will be minging.

your call, really...
Just damper, nothing advanced.
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Re: When replacing fork oil, do you strip the forks down completly?

Post by katana »

DefTrap wrote: Mon Jan 08, 2024 1:45 pm I do, but only because it's generally pretty easy (and normally because my seals tend to go bad before the oil iyswim) and you get to see any other wearing parts up close while you're there. My only advice is to crack some bolts before you genuinely start to dismantle as this may give you an idea how tough the job might be. Typically the longer it has been since it was last dismantled, the more of a pig it will be.
It is pretty easy, loosen the fork caps, then remove the wheel, brake calipers and undo all the associated clips. Then undo the clampes on the forks and they should just drop out.

So far I have drained the motor oil, and taken the tank and seat off. So I can start on everything else I need to look at on the bike.

How often are you supposed to change fork oil? Some allegedly change the oil every six months!
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Re: When replacing fork oil, do you strip the forks down completly?

Post by katana »

Le_Fromage_Grande wrote: Mon Jan 08, 2024 3:11 pm If it's damper rod (and it probably is) just empty the oil out and put some fresh in, quite a lot of forks have drain screws on the forks so you don't have to take them out. Cartridge forks are a bit of pain to get all the old oil out of, you need to pump the cartridge to get it to come out.
Have always taken the forks out, so I can set the right air gap on the forks. So the forks have to be verticle to do that so off the bike is the only way.
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Re: When replacing fork oil, do you strip the forks down completly?

Post by mangocrazy »

katana wrote: Mon Jan 08, 2024 3:27 pm How often are you supposed to change fork oil? Some allegedly change the oil every six months!
Depends on mileage I'd say. With damper rod forks (which I suspect your Fazer has) it's a lot easier to change the oil and it probably has an easier life. It's also likely to be heavier in viscosity than that in cartridge forks, so tends to last longer. I'd say every two or three years as a rough guess.
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Re: When replacing fork oil, do you strip the forks down completly?

Post by Le_Fromage_Grande »

katana wrote: Mon Jan 08, 2024 3:32 pm
Le_Fromage_Grande wrote: Mon Jan 08, 2024 3:11 pm If it's damper rod (and it probably is) just empty the oil out and put some fresh in, quite a lot of forks have drain screws on the forks so you don't have to take them out. Cartridge forks are a bit of pain to get all the old oil out of, you need to pump the cartridge to get it to come out.
Have always taken the forks out, so I can set the right air gap on the forks. So the forks have to be verticle to do that so off the bike is the only way.
The slight angle isn't going to make enough difference to notice.
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Re: When replacing fork oil, do you strip the forks down completly?

Post by katana »

Le_Fromage_Grande wrote: Mon Jan 08, 2024 4:32 pm
katana wrote: Mon Jan 08, 2024 3:32 pm
Le_Fromage_Grande wrote: Mon Jan 08, 2024 3:11 pm If it's damper rod (and it probably is) just empty the oil out and put some fresh in, quite a lot of forks have drain screws on the forks so you don't have to take them out. Cartridge forks are a bit of pain to get all the old oil out of, you need to pump the cartridge to get it to come out.
Have always taken the forks out, so I can set the right air gap on the forks. So the forks have to be verticle to do that so off the bike is the only way.
The slight angle isn't going to make enough difference to notice.
I believe I can notice :shock: I didn't notice the lack of air on the forks of my bike.