Adding fork oil without removing forks

Joeywhat

Joeywhat

Joined
Apr 5, 2018
Messages
158
Location
United States
Bike
2006 ST1300 - Black
Can I add fork oil without removing the forks? I understand getting the correct amount in there will be a concern, but it's one I can handle. Just wasn't sure how accessible the forks are as I'm out of state at the moment and can't just go look at the bike.
 
Possibly, I have the Heli gen 3 and can get to the cap no problem but on my coworker's 03 with the MCL Riser half the cap is blocked. Picture of my ‘10.
 

Attachments

  • A11CD739-F133-458D-B433-77E80CC83D65.jpg
    A11CD739-F133-458D-B433-77E80CC83D65.jpg
    157.1 KB · Views: 38
You need to remove the forks to do it right. You'll have to remove the handlebars at a minimum. And it will be crazy trying to siphon out old fluid, you cant get a tube down the fork leg with the spring in it. I tried. You really should drain them and rinse them with a solvent a few times. Otherwise you'll not remove all the sediment at the bottom of the forks.

Old saying... If you can't find the time to do it right, where will you find the time to do it twice?
 
I'm not removing old fluid, only topping off. Had a seal leak due to dirt and I'm not going to tear them all apart for a little fluid when everything else is fine.

I'll do a full service when I have new seals, washers springs, etc. That's likely a winter project.
 
To the other posters here, it seems we are dealing with an 1100 here. Note to Joey - put you year and model with your avatar.

You can't just "top the fork off" with oil. There is a specific height that the oil must be at and it isn't to the top. You have no idea how much oil you have lost, so it would be impossible to add the correct amount.
 
You can do it. I've done it on a couple bikes. On the ST1100 non ABS, there are fork oil drain plugs on the bottom of the fork, so you can drain and refill. I do recall that reinstalling the cap on one fork was a real PITA requiring a couple helpers. That being said, it is best done by removing the forks which is not that hard. At the time, I didn't want to take everything apart so I replaced the fork oil with them still on the bike.
 
RobbieAG said:
You can do it. I've done it on a couple bikes. On the ST1100 non ABS, there are fork oil drain plugs on the bottom of the fork, so you can drain and refill. I do recall that reinstalling the cap on one fork was a real PITA requiring a couple helpers. That being said, it is best done by removing the forks which is not that hard. At the time, I didn't want to take everything apart so I replaced the fork oil with them still on the bike.
Click to expand...

He isn't draining the forks. Helps to read his posts.
 
unless you had a huge mess with the leaked oil, it probably didn't leak enough volume to make much difference, so its not a big deal whether you try to replace the oil or not. As Bush said, you'd only be guessing anyway, so doing nothing is probably just as good as doing something, and takes less time.
 
Only problem there is the drains will not get all the old fluid out. You need the forks off, turned upside down and pumped to get as much out as possible, then measure the height of oil, with the spring removed and the fork collapsed.
 
since we don't know the year or ABS/non-ABS its hard to say. ABSII bikes have no drain plugs.
 
Joeywhat said:
It's a 96, no abs.
Click to expand...
I do fork oil without removing the forks all the time. The stock measure is to be 180mm from the top of the tube with the springs removed. That's the kicker.... if you are going to measure the correct air gap you have to remove the springs. At that point you aren't far away from just removing the shock if it needs a rebuild.

Mine did not need a rebuild and I was just changing out the springs. The first time was for Progressive units and they called for a 160mm air gap and the recent change was to straight wound Racetech springs and they require a 130mm air gap from the top of tube.

I'm not that fancy in my fill gauge and I use a straight long screwdriver. Two methods you can employ if you're leaving the shocks in the tree.... Either measure the gap in front and the rear of the two, add them together, then divide by 2 to get your fill if it where vertical and even all the way around... or use a flashlight and measure the far right and left, which should be about mid-point.

I should mention... I don't care if I'm 5mm off and the difference between the right and left "official" fill marks is something like 2mm. I just don't think it makes that much of a difference. I would go with the recommendation of whichever spring you have mounted, get real close to the fill (within 5mm preferably to the high side).

I would agree that if you don't have a huge leak, the amount you will lose should be fairly minor. However, rebuilding isn't difficult and wouldn't take a day.

However, I would disagree that you need to pull them to get a good flush. An option would be to buy an extra bottle of fork oil per side and fill, compress, drain 2x's before filling to the correct level. I would be hard pressed to think that a double flush would leave any amount of old oil that would be concerning. It's what I did because my seals are still good and I didn't get hardly any old oil the last drain. (I could tell because I used Belray 10w last time, which is a much darker color than the Honda 5w).

However... to each his own...

If you would like to borrow a damper tool... pm me and pay for shipping and I'll send you one. Or, shoot me $10 and shipping and I'll make you one.

20180521_201810.jpg
 
Yes, the plan if the drains are accessible is to drain, run some oil through once or twice and then fill. I was also planning on measuring similarly to how you described.

I have an overhead hoist I can use so I should be able to get the forks pretty close to level to check height.

I'm only home 2 days every other week right now, so I'm not spending a whole day to do something when I can be out riding and visiting friends and family. I'll get it draining first thing in the morning, check mid day and refill/drain again before doing the final fill. Weather should be nice and I have some other bikes to ride anyways.

Thanks for the guidance.
 
Joey - On the ST1100s, the fork drain 'screws' can be cantankerous to get to and get out, IIRC. I used an air wrench and had the proper end welded to a long extension for that purpose.


BAD ADVICE DUE TO OLD AGE MEMORY - PLEASE IGNORE UNLESS ABSII MODEL!!!! ;-)
 
Last edited:
I'll make sure to use caution. Are they typical bleeder valve style like on brakes, or a screw I can use a cordless impact with?

If I can use my impact I have a wide assortment of bits and sockets so I can get a good fit.
 
You must log in or register to reply here.
Back
Top Bottom