Front fork oil level / weight / viscosity / approximate capacity ???

Question edited for clarity.

RM85 Fork Specs. Bound to be the same forks

When adjusting the fork oil level, compress the outer tube fully
without the fork spring.
? 09943-74111: Front fork oil level gauge
? Fork oil level (Standard): 124 mm (4.88 in)
? 99000-99001-SS5:SUZUKI FORK OIL SS-05
? Standard fork oil capacity (each leg): 351 ml
or an equivalent fork oil
(11.86/12.36 US/lmp oz

Free Service manual for the RM85

https://www.manualslib.com/manual/824675/Suzuki-Rm85.html?page=164&term=fork+oil&selected=1#manual

Lots of Service Manuals for around $34

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More here.

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..

When reassembling the forks on a motorbike the main spring and all other internal components should be in the fork tubes then add the oil, as to weight I assume you mean fork oil viscosity. Fork oil for general use is usually 5w or 10w but you need to look up the specific oil type for your bike, also the capacity is unique to each bike but you can measure the oil by pouring the required amount into the upright tubes make sure that the levels are the same, use a straightened wire coat hanger and measure the level in each fork so that any differences are reduced so as to not affect the safe handling of the motorbike as uneven forks can be very dangerous.
Look on youtube to find videos of fork oil change etc.

I have a 2001 Suzuki vz800 marauder. I'm doing the front fork seals but I dont know exactly what weight I need to put in the fork. Some say 10w and some say 30w. Can you please help

Change fork seals and cha he fork oil sounds like dirty fork oil or low on oil but do change oil and seals gx luck if u want a stiff front end can also use thicker oil check OEM oil viscosity and what they recommend for stiffness

You may not have enough oil in the front forks or you may been a heavier viscosity of oil. I'm sorry but I don't have the oil capacity for your "Low Sportster". All I have is for "Hugger" models. They take 10.7oz. "wet" and 12.1 "dry". The difference between "wet" and "dry" is that if you simply drain and refill the front forks, it's call a "wet" oil change. If you disassemble and clean the forks of all oil inside, it's called a "dry" oil change. Contact the service department of your local shop and ask them how much oil goes in the front fork. To change the oil, there is usually a small screw in the trailing side of the lower fork slider down near the axle. Take these out and the oil will drain to a certain degree. Hold the brake while working the forks up and down with your weight to get all the oil that draining will get out of them. If you want all the oil out, you'll have to disassemble the fork tube. I would not do this if the seals are not leaking. Replace the screws in the sliders and then remove the top cap from one tube at the time and refill the tube with the specified amount of oil. Sometimes, the top caps can be difficult to get back in due to the pressure of the large spring in the front fork tubes. You may need a tool to compress the sping. I'm not sure on the "Low" model. I've always managed to the top caps back in without any special tool but I've never done a "Low" model bike. Harley uses what they call their "Type E" fork oil. I do not know what the viscosity of this oil is so I always use PJ-1 30 weight fork oil for most applications. Use only fork oil as any other oil may have a tendency to foam thereby negating any dampening action of the forks. If this doesn't solve your problem, you may want to check into changing the springs in the front forks. Progressive Suspension and others make kits for this.

Good Luck
Steve

I'm sorry but I don't have the specs on the quantity and type of fork oil for your year and model bike. I work on the older bikes that the dealers will no longer service. But, I can describe the difference between the "wet" and "dry" conditions of the fork assembly. If you take the front forks apart, clean them out, and put them back together with no oil in them, they are considered "dry". For a simple drain and refill type oil change on them where you don't get all the oil out of them, they are considered "wet". I hope this helps, You can call you local dealer's service department and they should tell you the quantity and viscosity of the oil that goes in the front forks on your machine. They'll tell you something like 6 ounces of "Type E" oil, for example. Harley-Davidson uses these types of specs to describe their oils. If you go to a website for fork oil, like PJ1, they may give a cross reference or equivalency chart for converting H-D "Type E" to their oil. I think that would be their 30 weight oil. If the front end seems too "stiff" with 30 weight, you can drop down to 20 weight. I think Honda makes a 25 weight but not sure. Your Harley won't mind the Honda oil. BG.

Good Luck
Steve

Since your bike is a 2011 model, I'd take it to the dealer and let them check out the loss of power. On the front end diving, you may need to put a heavier viscosity oil in the front forks. You'll have to drain the forks and then refill them with the proper amount of oil of a heavier viscosity. I think the forks come with H-D type "E" oil that is supposed to be about 30 weight. Use only "fork oil". You cannot use engine oil.

Good Luck
Steve

Yes your fluid may need to be changed if you want a more firm front end. I don't know what type of fluid you have in the forks now but what you need to do is to go with a thicker oil. In my '94 FXDWG, I went to PJ1 30 weight oil. Since I don't have a book on your late model bike, I can't tell you how much oil to put into each tube. There is a "wet" and a "dry" quantity to add when you've drained them. If you simply drain the oil and refill the fork tubes, use the "wet" quantity of oil. If you disassemble and clean the tubes out, use the "dry" quantity when you refill.

To drain the oil, look on the trailing side of the fork sliders. You'll see a screw or a set screw in the slider. Take this plug out and some of the oil will simply flow out. To get all of it out, hold the front brake and push down on the handlebars. Now, oil will spray everywhere so don't do this job in your living room. Once you get the oil out of both tubes, reinstall the plugs and refill the tubes one at the time by removing the top cap out of the tube and pouring the prescribed amount of oil into each fork tube. Ride the bike and see if the front suspension is too soft, too firm, or just right. Remember, the heavier the viscosity of the oil, the more firm the front suspension is. If you can't get it right, you might want to consider changing the springs in the fork tubes.

Good Luck
Steve

To change the fork oil, look down on the lower part of each fork leg just above the axle on the backside of each leg and you'll find an Allen plug or small screw. Take this screw out, hold the front brake and push down on the front forks. The fork oil will come out of the tube. Do both sides at the same time. Once you get the oil out of them, reinstall the drain plug. Then, take the large hex cap on ONE TUBE AT THE TIME and pour the correct amount of the correct fork oil into each tube. There is a specific amount of oil that must be poured into each leg. Since you simply drained your forks instead of disassembling them, you should use what is known as the "Wet" quantity of oil. I'm pretty sure your bike takes 9.0 ounces of oil in each leg. Call your local dealer and they'll tell you how much oil to put in. Your bike came from the factory with "Type E" oil in the forks. The viscosity of the oil determines the dampening effect of the forks. Heavier oil will stiffen the front forks, a lighter viscosity of oil will make the front end softer. You can check the Internet for fork oils and they should give you a comparison of what weight oil is equivalent to "Type E" oil. I think PJ 1's 30 weight oil is the same as type E Harley oil. Use only "fork oil" in your front forks as it has special "anti-foaming" agents in it. If the oil foams up, you'll lose the dampening effect in your forks.

Good Luck
steve