Fork oil recommendations?
Road Master
Joined: Aug 2008
Posts: 1,027
Likes: 163
From: Grapevine Texas
By the way, didnt catch exactly your ride but mine was about 26oz per side, so I had plenty, since I ordered 3 quarts. Check, verify with your service manual for your ride. More will be stiffer, less will be softer.
Outstanding HDF Member
Joined: Nov 2006
Posts: 2,049
Likes: 6
From: Oregon City, OR
The first time I have the forks apart (or if it's just time to change the oil) I have always switched to SE fork oil and seapped out the riser bushings for the poly ones. The SE stuff has always been firm enough for me and the poly bushings are a huge improvement over stock.
Tourer
Joined: Dec 2009
Posts: 406
Likes: 13
From: Langley, BC. Canada
Correct as I just did a member's here when he converted over to duel disk. I know that I have about 1/3 or so of a bottle left out of 2 bottles. If you guys wish to make your ride stiffer than with stock forks just weld up the holes in the seat pipe and re-drill some more but smaller. This is how you did it before the invention of cartridge emulators. Heavier oil means more stiction = your forks work less efficient because they are slowed down.
Also, will increasing the fork oil level work the same as a twin chamber fork where it stiffens the last 1/4 of travel?
Last question. Is there any way to stop, or reduce, that horribly annoying topping out of the forks?
Thanks very much.
Tourer
Joined: Dec 2009
Posts: 406
Likes: 13
From: Langley, BC. Canada
I have a 2001 FXDWG Wide Glide with 41mm forks. I hated the soft bouncy nature of the forks and the clanging when they topped out. It was also very difficult to stop cleanly with just the front brake, due to the rebound effect of those soft forks.
I just changed my fork oil to 15w and it made a huge difference. The bouncy nature is gone, I can stop without looking like a rank beginner and the topping out is dramatically reduced. The forks give me much more confidence in corners and I wish I had done this sooner. I used Maxima Fork Fluid, but any good suspension fluid should work as well.
It is so easy to change the fluid in these forks. Just remove the 1 3/8" bolt on the top of the fork tube and then remove the oil drain screw on the back of the bottom of the fork tube and let the oil drain. Then put the screw back in and pour 12 oz of fluid in the top and put the bolt back in. You have no issues with spring pressure or anything else. A quick and easy job.
I just changed my fork oil to 15w and it made a huge difference. The bouncy nature is gone, I can stop without looking like a rank beginner and the topping out is dramatically reduced. The forks give me much more confidence in corners and I wish I had done this sooner. I used Maxima Fork Fluid, but any good suspension fluid should work as well.
It is so easy to change the fluid in these forks. Just remove the 1 3/8" bolt on the top of the fork tube and then remove the oil drain screw on the back of the bottom of the fork tube and let the oil drain. Then put the screw back in and pour 12 oz of fluid in the top and put the bolt back in. You have no issues with spring pressure or anything else. A quick and easy job.
Tourer
Joined: Jan 2010
Posts: 304
Likes: 1
From: Woodburn, OR. USA
I'm a master Refrigeration/HVAC/Controls mechanic by profession, but a "newb" to working on bikes... so tell me, how does fork oil get "nasty", as I'm not seeing how it gets exposed to high heat from mechanical friction like in a crankcase, and it should be sealed from moisture contamination?
My '06 Street Bob rides awesomely as-is, but is a couple hundred miles away from it's 10K service, and I'm getting my ducks in a row so I can wrap my brain around it as I'm a DIY'er by nature.
Thanks for any schoolin' you can give me!!
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Tourer
Joined: May 2010
Posts: 428
Likes: 4
From: Santa Ynez, Ca
Good info,,I'm going to try 15wt oil in my 2010 WG as they bounce a bit too much for my liking. A tech at Racetech told me several years ago when I was having my ZX12R forks rebuilt that the oem oil can be less than perfectly clean during the assembly process and as the oil foams in the tubes it picks up every micron of dirt that gets pass the seals as well as the debris that is left inside the tubes during assembly. I don't know how accurate that is but when he drained the oil out of my 12's forks it was black. Certainly didn't look too clean to me however it got that way.
Seasoned HDF Member
Joined: Feb 2008
Posts: 22,999
Likes: 11,439
Keep in mind different years bikes have different service recommendation.
My 2007 RG calls for nothing other than a 50K service no fork oil changes nothing till 50K .
Winter came bike had 42K on so I decided to do the service early.
This is how the seals and bushing looked with 42K on them and that nasty oil Hd puts in them. Anyone that knows what they are looking will see there is so little wear you could without and problems run many more miles.
My 2007 RG calls for nothing other than a 50K service no fork oil changes nothing till 50K .
Winter came bike had 42K on so I decided to do the service early.
This is how the seals and bushing looked with 42K on them and that nasty oil Hd puts in them. Anyone that knows what they are looking will see there is so little wear you could without and problems run many more miles.