Kawasaki ZX-10R Forum banner

Fork Seal Time. What Else?

Gen 4: 2011-15 
4K views 26 replies 8 participants last post by  scout 
#1 ·
Hi all,

Forks are oily at 60,000 miles. Going to replace dust and oil seals with OEM.

Anything else I should do While they're apart? Like bushings?

44065-0026 BUSHING-FRONT FORK
44065-0038 BUSHING-FRONT FORK,SLIDE

Also, any good fluid recommendations?
 
#4 ·
Couple things to consider.

OEM or SKF oil and dust seals are best and last the longest. Make sure to grease both when you put them in.

You don't HAVE to change out the bushings, check the Teflon and see if it's worn. Otherwise there really is no benefit or performance gain to changing out bushings every time you change seals.

Inspect and polish your fork tubes for knicks.

Make sure both sets of o-rings on the cups are intact, otherwise you lose the seal in the tube and damping.

Inspect the valving shims. They have a tendency to distort and break over time on the BPF.

If you have stock valving, use the same viscosity oil that is recommended by the OEM. You'll save yourself the headache. If you want a bit performance gain, bump up to full synthetic and it will smooth out the valving feel,but make sure to keep the same viscosity.
 
#6 ·
Redline makes great suspension fluid too. Again, be careful when choosing the proper viscosity. Manufacturer weights are sum what ambiguous. Silkolene Pro RSF 2.5 wt is comparable to Maxima 5 wt., go figure. Both Redline and Silkolene make great fully synthetic fluid, this last longer and changes less in viscosity concerning temperature ranges than non synthetic fluids.
 
#7 ·
In suspension full synthetic oils don't really "last longer" So many contaminates get into the oil it doesnt matter what one uses.

Also the thickness of oil is more important than synthetic vs non synthetics. Some of the most stable suspension oil out there is Silkolene RSF 2.5 which has a Viscosity Index of 464.00 and is not a synthetic oil. Motul Factory Line 2.5 is only 112 and is full synthetic. Silkolene Full Synthetic 02 is only 212 VI.

The biggest advantage of synthetic is how the oil feels as it flows through the valving. It smooths everything out. Thats why pretty much every aftermarket cartridge uses full synthetic.
 
#10 ·
Silkolene Rsf, synthetic technology, straight from their website. Whatever that means. Correct , viscosity index and viscosity are very important due to the increased heat that a shock creates. Less important in forks although due to the fact that most people don't change their suspension fluid nearly enough. Note that somebody was talking about 60,000 miles on their suspension fluid here, that's way too long in between service. This Viscosity index indicates how an oil will perform over a wide ranges of temperature change. Therefore I use an oil with a high VI in both fork and shock. Why not? The price is negligible. Hell, many people will do you a fork oil change and not even touch the shock. What sense does that make. Oil degrades so slowly over time you can't feel that the thing is working like shit. At least until the thing IS working like shit.
 
#13 ·
That is great! :lol:

Think this will buff out?



How about the other fork from that set with the cap loc-tited to the rod and the spring retainer jammed and frozen into the adjuster?



It's not all gloom and doom though as I have had some really cool stuff come in lately too like these Moto2 forks
 
#15 ·
One thing thats helped me with oils is to see that chart posted. Im sorry to be the lame ass who posts it, again, but I have found it useful.....

http://www.peterverdone.com/wiki/index.php?title=Suspension_Fluid

On the chart, you'll see a column that is labeled as "cSt". That is an abbreviation for "centistokes"

This is just a finer measurement than the typical "W" we use. Almost like measuring a board..Your measurement will be way more exact if you are able to measure that board in inches, vs only being able to measure it , in feet.

If you find the cSt number of the oil you like, its much easier to buy something thats similar, if not identical.
 
#19 · (Edited)
Yep, that is exactly what all the professionals want you to think.
I think he meant to say.. not all the professionals, just the "egocentric" ones.

LDH has a wealth of knowledge on suspensions but his contribution to the OP's question on suspension was a smart ass reply, not only, not addressing the original question but knocking people here on the forum that where trying to help.

I thought LDH's reply was dickish and not funny at all. Why not just try to help and
share his vast knowledge instead of knocking people or better yet just
don't post at all. We'll trudge through this suspension stuff without him.
 
#21 ·
When it comes to something as important as the suspension on a motorcycle there is no "trying" to help. You either do it correctly or you do not do it at all. There is way too much at stake if it is not done properly. In the last month I have seen no less than 3 different do-it-your-selfers completely screw up their forks after replacing fork seals or doing their own routine oil change. They show up at the track and then complain something isn't right when their forks won't even compress an inch or move like molasses in winter. Additionally I have seen some very questionable work over the years from Pro tuners. If people that have been doing this for decades cannot seem to get it right I have little faith in the general public not making mistakes. Way too many people take too many shortcuts or simply fail to pay enough attention to detail and the results can easily be detrimental. In an environment where a single spacer incorrectly installed can cost you both stroke and overall length at the same time, you can easily make a bike that was perfect handling before a service into one that will wash you right off the track in even the slightest of turns.

As far as my reply specifically. The correct answers were already being published by evallarta1, a seasoned professional, so there is no need for me to to repeat or even add to what has already been covered, but I can damn sure point out the absurdity of others wanting to appear proficient when they are not. That being said you aren't hurting my feelings one bit if you want to ignore me.
 
#20 ·
Ya, I was not trying to down play the information and skill that a Professional has obtained over the years. It is not like I think I am a professional when it comes to suspension. I do my best with the help of professionals in the field. Many Pros are willing to share knowledge and still be able to sell products, like Paul Thede. I think anything can be learned if there is a will to do it. I also think that if you are gonna be riding the bike, you should be the one turning the adjusters. It just takes time and testing to be able to feel the subtleties of a setting change.
 
#22 ·
It's a good thing that you are passionate about motorcycles. You are in the right place. The OP was trying to say...... just be helpful or say Nothing at all. I could walk around bashing everyone's construction projects because I AM A MASTER CARPENTER. But what would be the point. Or I could just constructively say hey " if you glue your wooden miter joints, you would never develop gaps like you have there". That's all.....
 
#25 ·
99% of the riders out there could ride around with a "fixed" suspension
(and some do) and would have no impact on them at all yet alone
having their sag not set properly or not the perfect oil in the forks.

Club racing and up different story but represents a very small percentage
of overall riders.

Suspension is pretty easy to work on, not sure why some think it's
black magic, tricky or only suitable for a professional to work on.

Sure I don't have a shock dyno, Vacuum or nitro equipment but come on,
oil changes, springs, valves, seals are easy to anyone that can reasonably work on their bike.

Changing oil forgetting to tighten drain plug or working on brakes far more dangerous then changing a set of fork seals.

And yes, many have stripped their drain plugs, cracked their oil pans or
not tightened their oil filters correctly, etc. so any work done on a bike can be dangerous but doing maintenance on your suspension no more dangerous
then doing other maintenance.

Yes, if you don't feel comfortable or don't understand something, then you should learn, ask for advice or take to mechanic.
 
#26 ·
Exactly.......a person that can't do shit should not be working on certain things. I have done plenty of technical jobs and with a bit of thought and skill all goes well. I have not jacked up a set of forks or shock in my 53 years alive. I agree professionals should be sought and paid for their expertise in many ways but to say only pros can adjust or service forks and shocks is ludicrous at best.
 
#27 ·
Just get the newest seals for the g4 forks. '11 seals blew out on mine about 25k miles or so but the '13 seals still are excellent at 75k miles.

Don't dork with after market as appears that kawa upgraded their fork seals for the USA market. If you're not USA do whatever.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top