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Fork oil replacement for the less knowledgeable

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Hi all, one of least maintained item on my moto is the fork oil. Can anyone provide me a simple step by step process on how to do this (pictures would also be great)? I know how to remove the forks (don’t have to describe that), I’ve just never done the internal… 😢 Thanks in advance.

Alex

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There is a right way and a wrong way to do this. If all was good and clean inside, and you were just changing oil for ,, saw a weight change, or level,, then a simple drain and refill could be described in a few words. But to do that for a compleat disassembly,, is a but cumbersome. You really need to get your hands on a service manual. The forks need to be disassembled, cleaned, inspected for wear and damage, reassembled, and filled with oil.

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My manual says each fork holds 720 ml. It also says the oil level is 122 mm. Should I use the 122 mm height, or the 720 ml volume? Will 720 ml give me a 122 mm level, or should I just check the oil level? I put new springs in my forks but I didn't change the oil then 😢 . Do I need to take the forks completely apart again, and then add oil? Could I just measure how much old oil is in them, and add the same amount?

Also, what is a good fork oil to use?

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Thanks bronco78, acutally the simple drain and fill was my target. I understand the complexity of the forks and that is why I wrote the thread... I do have a manual, but they describe the entire process which is what I'm trying to avoid. But if I can't I'll go back to the manual. 😢

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Thanks bronco78, acutally the simple drain and fill was my target. I understand the complexity of the forks and that is why I wrote the thread... I do have a manual, but they describe the entire process which is what I'm trying to avoid. But if I can't I'll go back to the manual. 😢

OK,, as long as you understand,, your not really maintaining them in the best possible way 😢

Once removed, back off all clicker adjustments, take the fork cap off, the inner tube will now slide down, take a 17mm open end wrench, and slide it in the top of the spring, holding the damper rod, unscrew the cap from the rod. remove the spring. Dump the oil out of the tube, pumpping the cartridge a few dozen times. I let mine drain upside down for 30 minutes or so. As you will not be taking them apart to clean,, May I suggest you at least pour in some clean oil, pump the cartridge a few times,, then dump that, Continue till you get no more black streaks in the oil.

Once drained,, collapse the inner tube. pour in some oil, and pump the damping rod till no more air comes out. Fill fork to desired level, as measured from the top of the inner fork tube to the top of the oil. Once done with that pull the rod all the way up.... drop in the spring, pull up the inner tube, and re assembly it all.

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As much as I probably need it I really can't see myself spending the cash to have the forks revalved. What I was wondering is what is the weight of the stock oil and if I go to a slightly heavier weight oil will it stiffen the suspension a little. I ride on a mellow moto track and occasionally find myself bottoming pretty hard. Don't need a major change anything would help. I weigh 195 and am a 41 yr old "B" rider. What weight would you suggest? "S" model if that's important. Thanks in advance, John 😢😢

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My DRZ E had 3k miles on it and I had read so many posts about little grease on the steering head bearings I decided to tear into it. I also wanted to replace my fork oil with the Belray 5wt. To get to the point YES it was worth the effort and I did feel a difference…(improvement)

· First get your bike supported on some kind of stand so the front end can be removed.

· Remove the headlight assembly

· Remove the handlebar clamp bolts and lay the bars with cables attached back on the tank. You may just want to unscrew your speedo cable at the odometer.

· Loosen the big caps at the top of each fork leg.

· Loosen the big nut on top of the steering head stem. ( If, your going to grease the steering stem bearings.

· Take your front brake caliper off, hand tighten the two bolts back in for safekeeping.

· Remove the front wheel assembly.

· Loosen the 8 pinch bolts on the triple tree that hold the fork tubes.

· The fork legs should slide right out without much fuss.

· Work on one leg at a time.

· Hold the tube with one hand and remove the cap with a wrench (it is not that tight).

· Now pull the spring down with one hand (easy) and put a open end wrench on the nut attached to the top of the rod under the cap. Use your other wrench and unscrew the cap. (Set, on clean paper towel, don’t damage threads).

· Remove spring and the thin friction washer at the top and set aside.

· Now just hold your finger over the rod, turn upside down over a container and the oil will come right out.

· Compress and Extend the fork leg with a pumping action and just let it drain. There will be a small rod that wants to fall out. There is a small spring and a valve that will come out if you don’t keep your finger over the main rod.

· Turn the fork leg upright and keep it compressed ( the boot will try and extend it a little but keep it compressed when you measure.

· I just took a small carpenters combination square and set the depth for 4 ½ inches. It sat on the top of the tube and extended down inside real nice.

· Now add your new fork fluid until it comes to the edge of the ruler (about 24 ½ oz.).

· Now just put it back together.

· Put the clean spring back in with the washer on top.

· You will have to pull the rod up, or push it up to the top so you can get the cap to screw on. It is no big deal just fiddle a bit.

· Hold the spring down with the washer on top while pinching the rod with your thumb and index finger, then with the other hand screw the cap back on finger tight.

· With the wrench on the rod nut carefully tighten the cap back on. You don’t have to test your strength by stripping the threads here, just give it a tug to tighten.

· Now slide the inner fork tube up and using your hand start the cap and thread it down on the tube.

· Do the other fork leg the same way. Check your steering bearings before you put it all back together in the reverse order.

· The triple clamp pinch bolts are torqued to 18-20 lbs. which seemed like a lot considering the axle pinch bolts are the same size and the book calls out 13 lbs. for them. Use your own judgment.

· A little trick to remember is to assemble everything hand tight including wheel and caliper so things line up then do your final tightening.

· *****************************************************************

· For those of you checking and greasing the steering stem bearings take off the big nut.

· Remove the top triple clamp, it comes off real easy in your hand.

· Back off the jamb nut and the stem with lower bearing will fall right out in your waiting hand.

· Remove the top bearing with your finger.

· Clean, inspect, regrease in reverse order.

· The book calls out for the bearing retainer nut to be torqued to 32 lbs. I think that is to much preload personally. I just did mine hand tight until no clearance. I was able to use my old bearings and races so everything was seated ok.

· My bearing had plenty of white grease from the factory. I just added a gob of synthetic marine grease and called it good.

· The torque spec for the big nut on the top of the triple clamp was 65 lbs. I made sure I got that right.

· Everything else was pretty basic.

My first ride after doing this was a 55 mile killer in rocks and sandwashes over at Moab Utah. Normally I can feel the damping change as the oil heats up. On this ride it felt consistent the whole day and suddenly the rear shock felt a little harsh. The front end seemed to eat everything but the worst hits and really made it easier on my wrists. I did back off the clickers a couple notches on compression and rebound.

Maybe someone with some real computer skills will do the deed and take pictures for ya all. This was an easy job and no really special tools needed IMHO.

GOOD LUCK! HAPPY TRAILS!

LET’S RIDE!

Greg

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