Flushing fork tubes. What to use?

I'm changing my fork oil but not disassembling the entire fork. Is there any type of solvent, brake cleaner etc. that is recommended for squirting in the tube for a final flush?


How come you're not taking em apart?

I don't trust that all the solvent will come out when doing that. I'd just use some fresh fork oil if they aren't coming apart.

That being said I pretty much always tear them down to inspect everything.

Buy an extra bottle of fork fluid (same brand and weight you intend to refill with) to flush the foks with.

As stated above, I prefer to disassemble and thoroughly clean, but if the seals are good and you don't want to separate the tube from the slider, there's nothing wrong with flushing the assembly with fluid and refilling.

When you drain the original fluid, look for metal shavings, if you see some, bite the bullet and disasemble the forks.

Avoid using brake/carb cleaners, they will dry out your seals.

Disassembly is the only way to completely get all the crud out.

I use some cheap generic Dexron type ATF for this. Drain the oil and put come ATF in. Work the forks to loosen up the crud and drain. Repeat until the fluid comes out clean. On old neglected forks this can take 4 or 5 rounds of flushing. Let it drain for a while to get as much of it out as you can and then put tin your choice of fork oil.

The ATF is compatible with the seals.

Don't forget to pump the damper rod (cartridge assembly) to flush several times as well, it holds a fair amount of fluid in there. Watch out when you raise it to full stroke while full of fluid, that first pump after it builds pressure will squirt you real good out of the by-pass orifices near the top of the tube.

Dont worry about all the ones saying to take apart totally, its better but remember some NEVER even change their oil to start with. Inspect your oil good for any debris like metal and such really well. Maybe strain oil that you drain out thru a fine filter like you use for paint or some old t shirt, anything to seperate debris so you can see whats going on. Then flush like said with oil but after you drain really well, i put mine in the sun upside down for a little after ive pumped the rod so as most everything is out. The warmth and gravity will help and you can then flush out. Ive changed fork out without complete disassembly, its not the best way but you do get in done about 95% as good as complete tear down, so anything is better than nothing.

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