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All 650Fs 2016 cbr650f fork question

Badmechanic69

2016
CBR650F
Jun 4, 2022
Riding Since
2019
Hey guys, hoping someone can make my life a little easier with some knowledge.
So my 2016 cbr650f fork is leaking, and I was hoping someone could tell me the model of the Showa fork so that I could find an exact walkthrough somewhere on YouTube.

A little backstory- I changed the seals and the fork oil last November, so it held up for a few months, but either I did something wrong the first time or I have to find the reason it gave way so quickly again.

Any help is much appreciated. Thanks

PS
I’m a terrible mechanic but I try anyway.
 

miweber929

2014
CBR650F
650 Alumnus
Staff
Feb 13, 2015
Woodbury, MN
Riding Since
1975
It's just a standard 41mm Showa conventional fork. Nothing special about it compared to the 100's in use in the 90s-2000's.

If you've gone through 2 fork seals in less than a year I'd be looking for a nick in the fork tube or some other reason they are failing.
 

JRinKtown

2018
CB650F
Jun 30, 2019
Instead of going to that trouble, your oil seal likely just has some dirt between it and the tube, creating a leak path. Happens a lot on dual sports. The easy fix is to clean the seal with a SealMate strip (Google that), Fork Doctor device, or similar.

All you do is wipe the leg, release the dust seal, clean with solvent in the recess. then insert the cleaning strip up between the seal and the tube and turn it around the tube two or three times, then pull it out while turning. Once done wipe off any oil that seeped out, and bounce your forks hard a few times. That usually solves the leak. I've used that method many times over many years and it has never failed to stop a leak unless the seal is actually blown.

Since you've cleaned in the recess, it's then a good idea to ensure there is grease in the grease groove on the seal. To do that, put a small amount of grease on the upper part of the tube before you put the dust seal back in place and bounce the forks a few times and finish with a super hard bounce, then wipe off the excess grease on the tube and replace your dust seal.
 

Badmechanic69

2016
CBR650F
Jun 4, 2022
Riding Since
2019
Thanks for the responses.

question for JR:

if a decent amount of oil has already escaped the fork, which I think it has, is there a way to top off fork fluid? Because I am not sure that is possible on these forks And would probably be necessary.

thanks again
 

JRinKtown

2018
CB650F
Jun 30, 2019
Thanks for the responses.

question for JR:

if a decent amount of oil has already escaped the fork, which I think it has, is there a way to top off fork fluid? Because I am not sure that is possible on these forks And would probably be necessary.

thanks again
I can't answer that properly as I've never taken these types of forks apart. Perhaps someone else here will know.

If you clean the seal first though, at least then you will know whether you will need to do more than just top up, or not. Leaky seals can look like they lose a lot of oil but often it's less than it looks and makes little difference in performance. You could try to clean the seals as outlined above and test ride, assuming the cleaning stopped the leaking.
 

Brammers

2014
CBR650F ABS
Staff
May 30, 2014
Hampshire, England
Adding for oil is easy. Getting the right amount is not.

Grab the service manual (see our resources section) and read the procedure for changing the fork oil (which you might as well do at this point).

I've changed springs once and fork oil twice. It's not that hard, but it is involved.

J
 

miweber929

2014
CBR650F
650 Alumnus
Staff
Feb 13, 2015
Woodbury, MN
Riding Since
1975
Here’s what I would say: unless it’s literally been draining out the seal, like enough to form a puddle, you probably have not lost enough oil to make a giant difference in performance. Oil is one of those things that a drop can look like a huge amount.

Clean the seal and run it. If the fork feels wonky then pull it, drain all the oil out and refill.

Fork oil is not something measured by quantity but by the gilled distance from the top of the tube. So unless you know exactly how much is gone out, you’ll overfill it and make it worse.
 
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