jojococomo
Guest
The bike sat with only 300 miles on it with original owner. I bought it last September & have put the 10K on it.
Would sitting idle cause the forks to leak maybe?
Would sitting idle cause the forks to leak maybe?
Fork Oil Flush Recommendation
- Thread starter Warren
- Start date
Seals (not just fork seals) do dry out if the bikes not ridden. My first bike was an '83 Honda GL650i Silverwing. It only had 25,000 miles on it when I bought it in 1998 -- less than 2,000 miles/year. When I got it, the fork seals leaked and a couple of seals on the engine leaked as well. I didn't have money for repairs then, so I figured I'd just buy oil. But I rode the bike a lot, and averaged more miles/month than the previous owners had averaged in a year. By the time I'd put 3-4000 miles on the bike, nothing leaked.
So, I'd try riding it, but some kind of gaiter to protect the slider tubes from dried bug carcasses wouldn't be a bad idea. There are some foam gaiters that don't require disassembly of the forks to install.
"I usually get my tyres changed at a service interval rather than waiting till they're right on the limit to keep the labour costs down."
How does that work? Aren't the labo(u)r costs the same either way?
How does that work? Aren't the labo(u)r costs the same either way?
No, it wasn't me that modified the forks with a drain plug.
FWIW, the oil condition in forks isn't anything like engine or transmission oil. Not a lot of exposure to elements (combustion products and water vapor) and not a lot of huge changes in temperature. The oil does not break down under use. About the only metal particles it sees are the very few from the bushings, which rarely have any wear at all in 100k miles. The grunge you see is the little bit of seal material that is worn as time goes on. It blackens the oil quickly so it may seem really dark in just a short period of time.
The only time I change fork oil is if the seals are leaking or if I have to have the forks apart for some other reason. And, as has been said above, fork seal problems are usually from external things, like bugs and dirt on the forks or pits in the chrome plating.
Off road bikes are another matter. They are exposed to a ton more dirt and water. Usually they are also a lot harder on the shocks.
And, yes, leaving a bike to sit for years means the fork seals will probably be toast. The seals are lubricated by the action of the forks. If they aren't exercised, the seals will dry out and get stiff, then leak. This is not as common as the old days as seal materials have improved so much. There is also the problem of small amounts of corrosion on the fork tubes when sitting. Then when first moved they rub against a dry seal.
Last, sunlight. The seals themselves are not exposed to the UV of the sun, but, those dust shields are. They are the first line of defense for the seals by 'wiping' the dirt and grit from the fork before it gets to the seals. The UV degrades them and then the seals are exposed to more harmful stuff over time.
FWIW, the oil condition in forks isn't anything like engine or transmission oil. Not a lot of exposure to elements (combustion products and water vapor) and not a lot of huge changes in temperature. The oil does not break down under use. About the only metal particles it sees are the very few from the bushings, which rarely have any wear at all in 100k miles. The grunge you see is the little bit of seal material that is worn as time goes on. It blackens the oil quickly so it may seem really dark in just a short period of time.
The only time I change fork oil is if the seals are leaking or if I have to have the forks apart for some other reason. And, as has been said above, fork seal problems are usually from external things, like bugs and dirt on the forks or pits in the chrome plating.
Off road bikes are another matter. They are exposed to a ton more dirt and water. Usually they are also a lot harder on the shocks.
And, yes, leaving a bike to sit for years means the fork seals will probably be toast. The seals are lubricated by the action of the forks. If they aren't exercised, the seals will dry out and get stiff, then leak. This is not as common as the old days as seal materials have improved so much. There is also the problem of small amounts of corrosion on the fork tubes when sitting. Then when first moved they rub against a dry seal.
Last, sunlight. The seals themselves are not exposed to the UV of the sun, but, those dust shields are. They are the first line of defense for the seals by 'wiping' the dirt and grit from the fork before it gets to the seals. The UV degrades them and then the seals are exposed to more harmful stuff over time.
Last edited:
OP
OP
Warren
2
When I posted this thread I was not sure when to change the fork oil. After all of the replies I am still not sure but I am now more comfortable in not changing it until the fork seals start to leak which was the dealers recommendation and a some of yours as well. Thanks
JQL
Growing old disgracefully
Since I had a front tire cut at 12k miles, I decided it was worth the effort to replace the fork oil along with the tire. The wheel, fender, and calipers were easy enough to remove, just follow the manual. Be sure to loosen the caps with the top pinch bolt loose and the bottom pinch bolt still tight, you will also do the same in reverse upon installation.
I did not remove the bottom bolts, just removed the caps, springs and spacer pieces and drained them inverted. The fluid was rather dirty, not like ink but more like worn ATF fluid. Be sure to clean the outsides of the top tubes thoroughly, to avoid damaging the seals. 409 and paper towels got the dead bugs and grime off easily. I decided to follow the manual to a T and fill them to 124mm below the tops with them fully collapsed. Fuchs Silkolene is my brand of choice, there was just enough in a 1L bottle of 10W to get the job done. Be sure to use new o-rings on the caps, I found the old ones had swelled a bit.
All in all, a fairly easy job to do.
Brad
I did not remove the bottom bolts, just removed the caps, springs and spacer pieces and drained them inverted. The fluid was rather dirty, not like ink but more like worn ATF fluid. Be sure to clean the outsides of the top tubes thoroughly, to avoid damaging the seals. 409 and paper towels got the dead bugs and grime off easily. I decided to follow the manual to a T and fill them to 124mm below the tops with them fully collapsed. Fuchs Silkolene is my brand of choice, there was just enough in a 1L bottle of 10W to get the job done. Be sure to use new o-rings on the caps, I found the old ones had swelled a bit.
All in all, a fairly easy job to do.
Brad