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Baileyrock

30 min fork oil change- On bike

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Yes too much oil can cause hydraulic lock, reducing travel. Im saying on my 43 mm, I run 95 mm oil height and works fine (full travel), 100mm bottoms like smack( DINK).Thats why I dont understand how you are saying run 120mm and the spring rate dont matter. Springs rates always matter in combination with oil height, and oil weight.You'd have to be a feather weight, not to destroy the wheel bearings with 120mm on stock springs, it would bottom so hard and fast.

Maybe we arent talking about the same bike, I dont know.

Edited by spud786

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Springs rate is independent of fluid height. Fluid level is directly related to fork travel.

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Each independant, I suppose thats true, Ive always found anytime you change one of the major factors you start with a different platform to adjust.Ive always found ,anytime Ive upped spring rate it Requires less oil height, atleast if running the same weight oil.Oil height has its greatest effect in the last 25% of travel, if talking 12 inches , thats the last 4inch. If only talking 4.5 total inches like on a VFR, the greatest effect is in the last 1 inch or so of travel.Oil height doesnt reduce travel(unless) using too much oil causing hydraulic lock towards end of stroke, but the right amount of increase will stiffen the curvature of the stroke, but not reduce total travel.I had race tech do a set of forks with gold valves several years back, I sent them back twice, still no good in comparison to my original modified set up, That was not a good investment at all.

They didnt like having to redo them either, overall I fiqure, unless you have a tuner on site, thats willing to adjust or take them apart multiple times, which is what I needed, its really the only way. The first set up they sent me, just blew through the travel too much, I think those gold valves just open the oil flow too much. When I sent them back , they stiffened the slow sped valving , but I still had to run them at 2 out on compression(practically closed) to make them usable.

Edited by spud786

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post-8974-0-83791700-1380483919.jpg

The oil that came out was as dark as a cup of ristretto......

The new (Motul 7.5W) as light as a chardonnay.

Wilbers' specs are for a 170mm air pocket, went for 160mm. Pure speculation! :goofy:

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The "30 minute" fork oil change has turned into a 2 hour fork oil change. The oil lock piece got stuck at the bottom and I didn't have long enough tools to grab it or the damper rod when it falls back inside the fork tube. Took me forever to finally get it all lined up enough to hit it with a impact gun. Does the bottom lock nut look like it is in to the proper depth?

post-29105-0-40535700-1432322652.jpg

Edited by Corkey

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Yes, looks good as long as the copper gasket is on it.

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Well, there were a few challenging things with my forks on the bike "30 minute" fork oil change. It ended up taking me hours. I need some advice on whether or not I need do it over or not.

I'll cut out most of the details and hiccups accept for the few things that concern me with the job I did. It is a bit hard to explain but I will do my best.

Tire off, fork oil drained. No problems. Cartridge assembly out (the oil lock piece from the bottom of the tube came up with it. Great). Everything looked good inside. Now we come to the issues.

A. Because the forks were left on the bike and because I didn't have a long enough tool that could reach down and grab the damper rod to pump the cartridge full of oil (once there was oil in there) I ended up keeping the cartridge assembly in one piece and then just measured exactly 457ml of fork oil (as stated in the manual) using a syringe. Because I left the cartridge assembly in one piece I could not measure down 130mm into the fork tube. I just went with the 457ml.

1. Is using the stated volume (457ml) instead of measuring down to the fork oil (130mm) going to be a problem?

B. Because I wasn't able to pre-pump the cartridge with oil (because I didn't have a long enough tool to grab the damper rod and I because I left the cartridge assembly in one piece) I chose to just add the 457ml of fork oil and then screw on the fork cap.

1. Is it imperative that I pre-load the cartridge with oil?

2. I figured I could just compress the forks once everything is capped off and everything would work itself out internally? Am I wrong?

3. Do I need to do it over and/or open the cap to relieve pressure or something? Or is this a non-issue?

C. My spanner wrenches were so thick that I couldn't get one on the damper adjuster and one on the lock nut. The wrench would overlap because the nuts were so close. I ended up hand tightening and then doing my best to get them tight with the wrenches. I don't know how successful I was at getting them tight. I don't know that I really got them that tight.

1. Is it going to be a problem if that nut isn't torqued down?

D. For some reason the left drain lock bolt (on the bottom of the fork) didn't seem to go back in as deep as the one on the right side. Maybe by 1-2mm. I started them by hand so I don't think they are cross threaded.

1. Is this acceptable?

I rode it around the block a few times doing some hard braking and compressing the forks. It didn't bottom out or really feel any different than before the oil change. I really am not enough of a suspension expert to even know what to look or feel for when evaluating suspension. And again, I don't know if the method I used to change the oil was acceptable.

Edited by Corkey

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Well, there were a few challenging things with my forks on the bike "30 minute" fork oil change. It ended up taking me hours. I need some advice on whether or not I need do it over or not.

I'll cut out most of the details and hiccups accept for the few things that concern me with the job I did. It is a bit hard to explain but I will do my best.

Tire off, fork oil drained. No problems. Cartridge assembly out (the oil lock piece from the bottom of the tube came up with it. Great). Everything looked good inside. Now we come to the issues.

A. Because the forks were left on the bike and because I didn't have a long enough tool that could reach down and grab the damper rod to pump the cartridge full of oil (once there was oil in there) I ended up keeping the cartridge assembly in one piece and then just measured exactly 457ml of fork oil (as stated in the manual) using a syringe. Because I left the cartridge assembly in one piece I could not measure down 130mm into the fork tube. I just went with the 457ml.

1. Is using the stated volume (457ml) instead of measuring down to the fork oil (130mm) going to be a problem?

B. Because I wasn't able to pre-pump the cartridge with oil (because I didn't have a long enough tool to grab the damper rod and I because I left the cartridge assembly in one piece) I chose to just add the 457ml of fork oil and then screw on the fork cap.

1. Is it imperative that I pre-load the cartridge with oil?

2. I figured I could just compress the forks once everything is capped off and everything would work itself out internally? Am I wrong?

3. Do I need to do it over and/or open the cap to relieve pressure or something? Or is this a non-issue?

C. My spanner wrenches were so thick that I couldn't get one on the damper adjuster and one on the lock nut. The wrench would overlap because the nuts were so close. I ended up hand tightening and then doing my best to get them tight with the wrenches. I don't know how successful I was at getting them tight. I don't know that I really got them that tight.

1. Is it going to be a problem if that nut isn't torqued down?

D. For some reason the left drain lock bolt (on the bottom of the fork) didn't seem to go back in as deep as the one on the right side. Maybe by 1-2mm. I started them by hand so I don't think they are cross threaded.

1. Is this acceptable?

I rode it around the block a few times doing some hard braking and compressing the forks. It didn't bottom out or really feel any different than before the oil change. I really am not enough of a suspension expert to even know what to look or feel for when evaluating suspension. And again, I don't know if the method I used to change the oil was acceptable.

That's all screwed up as far as im concerned for cartridge fork set up, they need to be pumped bled and oil height measured .

and anytime you break the seals, best to replace(that's one issue I have with 30 minute oil change(your just risking seal issue). also you don't even have to even separate the forks, just to change oil., you do have to remove the legs, and the top caps and spring. No need to touch bottom fork bolt, unless your doing a complete disassembly.

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Dutchy, it depends on whether you're sure you managed to get all the old oil out. If so, adding exact Specified Volume of New oil should be fine. If not, then you now have more oil in there than Spec... depending on how much more you could Experience Hydraulic lock, Although I doubt that. Depends on how Long you let it Drain and whether you pumped to get most of the old oil out.

As far as the air in the rod sorting Itself out, yes, It will.

The big question is how much old oil was left in there.

A wire Coat Hanger or Other Length of wire is great for fishing out the damping rod.

I reckon you'll be fine Regarding lock nut and Lower bolt. They aren't going anywhere nor can anything really come undone given the hermetic set-up.

You'll only Know if Lower bolt is Loose if you start Losing oil through there. Check for leaks regularly. If your Model had Preload adjustment you might Notice it Turns to no effect but this is not the case.

If you crash and burn I accept no Responsibility

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I was just wanting to change the oil. My seals are fine as far as I can tell. Nothing is leaking externally. Based on the look of the fork oil I removed (clean looking) my guess was that the previous owner had worked on them not that long ago, possibly right before I bought the bike.

The whole point of trying the 30 minute oil change (for me) was to keep the forks on the bike so I didn't have to battle the triple clamp bolts under up under the fairing. And because it was my first time dealing with forks myself.

I let both forks drain a long time. I did remove the cartridge and pumped out all of the old oil before reinserting it. If anything there was a small spot at the bottom of the fork near the drain hole and very light residual oil left the sidewalls of the tubes. I know these small amounts add up and will be added to the overall quantity of oil I add. I probably should have used some brake cleaner to clean it out properly, but at the time my reasoning was that I didn't feel that small amount would make a difference (as I am sure there is residual oil inside the cartridge as well). However, maybe I am wrong. My manual (1998-2001) states "Fluid Capacity 457ml plus or minus 2.5ml". I put exactly 457ml in using a syringe.

My real concern is whether or not oil is able to make its way into the cartridge if it wasn't pre-pumped in prior to the fork cap being tightened (creating some sort of air pressure issue?). I don't know enough about forks/suspension to know.

Edited by Corkey

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Unfortunately my experience was not as fun as yours. Took me about 6 hours, about 1 hour to get the 2nd bolt out, over 4 hours trying to get the bottom bolt to tighten enough to seal. It would of course start to tighten and then spin. Spent over 4 hours trying everything I could think of, including impact. Finally took the fork tube to a Honda dealer and they got it to tighten. Gave the mechanic $10 for lunch money. After that, I will never remove that again. Of course first fork tube went fine, so I couldn't just leave it alone.

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I was just wanting to change the oil. My seals are fine as far as I can tell. Nothing is leaking externally. Based on the look of the fork oil I removed (clean looking) my guess was that the previous owner had worked on them not that long ago, possibly right before I bought the bike.

The whole point of trying the 30 minute oil change (for me) was to keep the forks on the bike so I didn't have to battle the triple clamp bolts under up under the fairing. And because it was my first time dealing with forks myself.

I let both forks drain a long time. I did remove the cartridge and pumped out all of the old oil before reinserting it. If anything there was a small spot at the bottom of the fork near the drain hole and very light residual oil left the sidewalls of the tubes. I know these small amounts add up and will be added to the overall quantity of oil I add. I probably should have used some brake cleaner to clean it out properly, but at the time my reasoning was that I didn't feel that small amount would make a difference (as I am sure there is residual oil inside the cartridge as well). However, maybe I am wrong. My manual (1998-2001) states "Fluid Capacity 457ml plus or minus 2.5ml". I put exactly 457ml in using a syringe.

My real concern is whether or not oil is able to make its way into the cartridge if it wasn't pre-pumped in prior to the fork cap being tightened (creating some sort of air pressure issue?). I don't know enough about forks/suspension to know.

I don't think it's an issue at all as all air will works it's way to the top is short order and things will be normal.

Also adding the exact amount of recommended oil vs a level will also be a mute item. I run an extra 10cc's in my forks to help firm them up slightly.

That's all screwed up as far as im concerned for cartridge fork set up, they need to be pumped bled and oil height measured .

and anytime you break the seals, best to replace(that's one issue I have with 30 minute oil change(your just risking seal issue). also you don't even have to even separate the forks, just to change oil., you do have to remove the legs, and the top caps and spring. No need to touch bottom fork bolt, unless your doing a complete disassembly.

You do Not "break the seal" with this method so no worries there related to the seals!

Again I don't suggest this is better then a full blown dis assembly of the forks, but for most it's a much easier way to improve your bike's fork performance.

It's really no different then changing your engine oil w/o performing a complete engine disassemble y to get out all the dirt and old oil, this method gets most of it and replaces most of the old oil replacing it with fresh. :beer:

I always use an impact wrench to remove & tighten the bottom cartridge retaining bolt with the fork fully assembled, using the spring pressure to hold the cartridge assm.

This method has only not worked once in my life.

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Because I wasn't able to pre-pump the cartridge with oil (because I didn't have a long enough tool to grab the damper rod and

You don't need a special tool, next time attach some rope to the damper rods.

img_0965.jpg

C. My spanner wrenches were so thick that I couldn't get one on the damper adjuster and one on the lock nut.

I wouldn't feel comforatble tightening the lock nut just by hand.

My real concern is whether or not oil is able to make its way into the cartridge if it wasn't pre-pumped in prior to the fork cap being tightened (creating some sort of air pressure issue?). I don't know enough about forks/suspension to know.

Yes, the oil will make it into the cartridge no problem.

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attachicon.gifDSC_3628.jpg

The oil that came out was as dark as a cup of ristretto......

The new (Motul 7.5W) as light as a chardonnay.

Wilbers' specs are for a 170mm air pocket, went for 160mm. Pure speculation! :goofy:

Hahaha Leon and Bert on the tubes. :fing02:

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So I am planning to change the fork oil in the next coming weeks. I have a 1996 VFR 750. Is the procedure same or anything is different? Any specialty tools are needed for 4th Gen? Any suggestions for fork oil for regular and normal street riding.

Any help or advice would be appreciated. Thanks folks.

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Hello Faran

How much do you weigh?

If you have the tools and time, taking the forks out is preferred. You can clean the brake pistons as well.

As for settings, I like using an sae10 oil with a 130mm air gap.

Measured with springs out, rod all the way down (tie string so you can pull them put easily after) and stanchions all the way down into the lowers. In between filling up towards the 130mm air you want to move the stanchions up and down say 10 times. And push the lower up and measure.

It is so much easier with the forks out and the time saved minimal. Just be methodical as per the workshop manual

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Hello Faran

How much do you weigh?

If you have the tools and time, taking the forks out is preferred. You can clean the brake pistons as well.

As for settings, I like using an sae10 oil with a 130mm air gap.

Measured with springs out, rod all the way down (tie string so you can pull them put easily after) and stanchions all the way down into the lowers. In between filling up towards the 130mm air you want to move the stanchions up and down say 10 times. And push the lower up and measure.

It is so much easier with the forks out and the time saved minimal. Just be methodical as per the workshop manual

Don't laugh, I am on lighter side, but with gear and everything I am ~150 lbs. :goofy:

Can I use 10W or 15W? http://www.ebay.com/itm/Maxima-56916-15Wt-Standard-Hydraulic-Fork-Oil-16-Oz-Bottle/162033379499?_trksid=p2050601.c100085.m2372&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D35356%26meid%3D5e32eec26ad04b79997e5f706b570d58%26pid%3D100085%26rk%3D1%26rkt%3D4%26sd%3D162033379499%26clkid%3D4736685344832721200&_qi=RTM2247625

I can completely remove the forks, not a big deal. But can oil be drained with the forks on the bike or no?

Thanks guys.

Edited by faran

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yes scroll up in the post for a picture of Bert and myself removing the bolt after having taken out the front axle

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You can use 15w oil, but as OEM spec is 5wt, that doesn't seem such a good idea to me!

Ciao,

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On 4/16/2016 at 6:56 AM, JZH said:

You can use 15w oil, but as OEM spec is 5wt, that doesn't seem such a good idea to me!

 

Ciao,

 

I agree, unless you changed the valving, or are going like something with Race Tech Gold valves (which flow a lot more oil) keep the stock recommended oil weight for the stock valving...

Matt

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just tried this, and it wont go back together, screw wont go into the bottom, like its not feeling any thread, i looked into the tubes, and can see the oil seal peice at the bottom and i dont think they are slotting together. im going to try and take the forks off today like the conventional way and try to get it back together.  Annoying since i commute daily to work, and have a wife who hates me being in the garage and i told her it only takes 30 minutes.  

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1 hour ago, StormShadow2 said:

is that 110mm air gap with damper in and springs out btw?

Springs out yes, damper rod in.

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Stormshadow, I think you will find it hard to get the oil-lock piece to slip back onto the damper from the top. Maybe you can fish the oil lock out from the top with a long piece of wire, magnets won't work as it is alloy not steel. If you get it out, stick it back on the end of the damper with small dab of grease to hold it during reassembly.

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i ended up taking the forks off today and doing the service the traditional way, and yes indeed the oil lock piece is the problem, i think it would be next to impossible to get it to all line up on the bike. 

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