Removing fork oil

[Oldnick]

I recently had my forks serviced  for leaks and they are now hard as iron, right from the get go. Not comfy and almost dangerous on a bumpy ride) I may shatter my delicate little wrists ). I understand (basically, theory) the idea of spring rate, oil viscosity and air in the system, and what I am feeling is _probably_ the need  for more air. AFAICS this means a softer start to the compression as the air compresses, which means that oil does not have to squeeze through the damper on the short sharp bumps (they are what I am feeling). Spring rate would have a similar effect, but I still have the same  springs.

Not trying to sound like a smartass, just that I have made the effort to think about this, from what I am reading and what I remember.

I also base my idea on the fact that the forks  were leaking, so my previous comfy ride was actually air-suspended

So anyway, what is the gen for removing oil. I have checked the manual and it looks like I open up and syringe-syphon stuff out. Have I missed an easier way?

Any help appreciated

[hubcapsc]

Take your forks off.

Get the caps off (special tool or ingenuity).

Take out the springs.

Turn them upside down for a day or so (get out every drop).

If you have a manual, put in the recommended amount of
oil, springs out, measured from the top, forks compressed.

Put it back together...

I can't predict if you'll like what you end up with, but the right
amount of oil will be in there...

-Mike

[John Schmidt]

If I need to soften the forks I just fill them with a couple ounces less than what's called for in the shop manual. Or in your case, remove an equal amount from each side just by removing the caps. A normal 6 point socket large enough to fit is all that's necessary but remember to loosen the top tree pinch bolts first. If you don't, you'll have much the same experience as spending the day trying to teach a sheep to lay down and roll over. By the end of the day, you'll be PO'd and have accomplished nothing. 

[WintrSol]

Page 13 of the shop manual: C and CT get 670+/-2.5cc left, 744+/-2.5cc right, CF gets 669+/-2.5cc left, 734+/-2.5cc right. Measured from top, it is C/CT 135mm left, 142mm right and CF 136mm left, 148mm right. It also says use Pro-Honda Suspension Fluid SS-8, whatever that is.

[Oldnick]

If I need to soften the forks I just fill them with a couple ounces less than what's called for in the shop manual. Or in your case, remove an equal amount from each side just by removing the caps. A normal 6 point socket large enough to fit is all that's necessary but remember to loosen the top tree pinch bolts first. If you don't, you'll have much the same experience as spending the day trying to teach a sheep to lay down and roll over. By the end of the day, you'll be PO'd and have accomplished nothing.  

HAHAHAH! Yeah, the right tool for the job there would be a Chestwinster 30/30 and such....or maybe a BBQ spit! Thanks for the hint man!

Actually I picked up on that because when I removed the  forks for servcing they specifically mentioned to loosen the caps _berfore_ removing the forks and to loosen the pinch bolts _before_ that. I did it to stay sweet with the mechanics in the shop. I find it's useful to be on good terms with any guy who works on stuff that is between you and the hard, hot road.

Anyway, if just a sip from the cup via the caps is all that's needed, then I can play to my hreart's content.

[John Schmidt]

Nick, just a "sip" as you put it would be my first try. Take it down an ounce or two, try it out for a time and go from there. I've done just that in the past, since I no longer ride hard and fast I want the front a bit softer and start out about 1.5 oz. under the suggested amount for each fork. If it still feels hard, or I get some front end bounce running down the street at 30-40mph, I'll drop it a tad more. You can always add some back in if you get it too mushy.

[art]

Automatic transmission fluid worked fine for me and after 5 years no leaks and comfy ride. Don't cost an arm and a leg either.  To drain fluid turn Valk upside down drain then right side up and fill.

[WintrSol]

ATF was the recommended fill, until they decided to put it in smaller containers and raise the price.

[Oldnick]

Nick, just a "sip" as you put it would be my first try. Take it down an ounce or two, try it out for a time and go from there. I've done just that in the past, since I no longer ride hard and fast I want the front a bit softer and start out about 1.5 oz. under the suggested amount for each fork. If it still feels hard, or I get some front end bounce running down the street at 30-40mph, I'll drop it a tad more. You can always add some back in if you get it too mushy.

Thanks for all your help man! I will give it a go as you suggest.

[Oldnick]

Yeah, with the ATF thing and all, at this stage I will try removing a bit of oil to see what happens, before I start diving in and turning my trike upside down and all. If I do that the sheepskin will fall off the seat and thgat could be a nuisance!

[Oldnick]

ATF was the recommended fill, until they decided to put it in smaller containers and raise the price.

HAH! Yeah. I* used to work with a guy whose brother made a small fortune repackaging epoxy and seeling it in tiny amounts for a huge profit...and his name wasn't Selley......

If I was filling the forks I would use ATF for sure.

[hubcapsc]

I used to use ATF in my Yamaha 100    ...

I know some folks who hate 10 wt fork oil and only use 15 wt fork oil.

Mobil 1™ Synthetic ATF (and all the others, I guess?) doesn't claim anything
about what weight it might be, though there's some fancy hoo-ha about
its density and viscosity on this data sheet:

       http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil_1_Synthetic_ATF.aspx

I hope SS-8 is the same this year as it was last year and will be next year...

-Mike

[WintrSol]

According to that link, that ATF has a viscosity at 40C (104F) of 36.3cSt, and a chart I found elsewhere lists SS-8 (10W) as 35.48cSt, hardly any difference, IMO.

[mark81]

With the different fluid amounts in each fork is it possible they got mixed up?  Why are there different specs for each fork?

[hubcapsc]

Why are there different specs for each fork?

They are different inside...



-Mike

[Oldnick]

Maybe they did get them mixed, but unlikely.The forks were done by the leading machanic in the shop, which has a very good rep. Far more likely a stiffer oil was used, or even that I was used to the amount of oil in leaky forks! It could also be that the dynamics of a trike are such that the "right" amount of oil is not the best.

One fork is compression damper, the other rebound. I guess it allows optimisation of each situation.

[jdp]

If it's too stiff I recommend lighter weight fork oil, I wouldn't put less oil.

[Oldnick]

If it's too stiff I recommend lighter weight fork oil, I wouldn't put less oil.

OK.Fair enough. May I ask why? A lot of guys do it and nobody else taht I have seen has saod not to.

[Jess from VA]

I would do just the opposite, use 10 wt std fork oil (or ATF), not heavier wt oil.   But use a couple ounces less than called for on each side.

My forks were rebuilt (by a dealer) with progressive springs years back, and for a year the front end was so hard a pothole could shake the bars out of my hands.  I went back and complained (it cost big money) and they wanted more big money to fix it.  So I just rode it that way.

For comparison, my other valk (also with progressive springs) has been leaking small amounts of fork oil on and off for years.  Yet, the ride and handling is just fine.

[Oldnick]

I would do just the opposite, use 10 wt std fork oil (or ATF), not heavier wt oil.   But use a couple ounces less than called for on each side.

My forks were rebuilt (by a dealer) with progressive springs years back, and for a year the front end was so hard a pothole could shake the bars out of my hands.  I went back and complained (it cost big money) and they wanted more big money to fix it.  So I just rode it that way.

For comparison, my other valk (also with progressive springs) has been leaking small amounts of fork oil on and off for years.  Yet, the ride and handling is just fine.

Hah! Maybe the leak is why they are OK? Only half joking. Mine felt great until they repaired and topped them up. I did have a dive problem, to left or right, under brakes, but a lot of that was a low pressure front tyre. My forks were probably _too_ low on oil; it was really leaking badly, and that probably did not help, but yeah there has to be a sweet spot.

The rebuild that was too hard. OOI did you try less oil or lighter oil?

[Oldnick]

OK. So today I finally got around to removing some oil. I removed 23cc from the right fork. Then I tried the left one. I could not get to the oil. In the right fork I could get a tube down the fork and extract oil with a syringe. In the left, there is no way to the oil. There is a flange that prevents that.

Aride test with many bends and corners and swerving on the straights left me feeling that less oil had made the ride far nicer and secure-feeling on my hands over sharp ruts and bumps, without affecting handling. I also reckon there is less headshake (trike remember)

The oil I extracted was a grey-black fairly opaque liquid that was, IMO, thicker than W10/ATF. The smell was not familiar; not ATF, not engine oil.

So my questions (and I may know the answer to the first):
- how do you get oil from the left fork? (I am wondering if you just remove the suspension bits??....I did not try that because I was fighting with my jack as well and did not think of it)
- does anyone have any idea what the oil is they put in there during servicing the forks?
    - given that the trike now feels better by removing oil I am not  desperate to change it, but it's useful for future reference

Thanks again for any advice

Nick