Fork oil checking

Having trouble? Need more info on something mechanical? Ask here!

Moderator: Modsquad

davenowherejones
Frequent Poster
Frequent Poster
Posts: 1817
Joined: Sat Jun 20, 2015 12:06 pm
Year: 2014
Color: Silver
Location: Hope, BC, Canada

Fork oil checking

Post by davenowherejones »

Is there any way of checking how much fork oil I have in my 2014 Forza 300?

I bought a crashed Forza from a scary backyard rebuilder. The front wheel hits really hard on potholes. I know this is not my dual sport DR650 but it should not hit scary hard on little bumps. It is fine on smooth roads.
j.d.b.
Forum Benefactor
Forum Benefactor
Posts: 255
Joined: Sat Jul 04, 2015 4:59 pm
Year: 2013
Color: red
Location: Michigan

Re: Fork oil checking

Post by j.d.b. »

Likely be easier and wiser to look up what's supposed to have and how much. Then just change it and know where you're at.
davenowherejones
Frequent Poster
Frequent Poster
Posts: 1817
Joined: Sat Jun 20, 2015 12:06 pm
Year: 2014
Color: Silver
Location: Hope, BC, Canada

Re: Fork oil checking

Post by davenowherejones »

j.d.b. wrote:Likely be easier and wiser to look up what's supposed to have and how much. Then just change it and know where you're at.
I agree but what is the procedure for changing the fork oil on a Forza? Also for my two hundred pound mass, what weight oil should I use?
j.d.b.
Forum Benefactor
Forum Benefactor
Posts: 255
Joined: Sat Jul 04, 2015 4:59 pm
Year: 2013
Color: red
Location: Michigan

Re: Fork oil checking

Post by j.d.b. »

Okay, a cursory search yields they use 10W up to 20W fork oil. Heavier oil damps harder, lighter will damp less. If the oil weight is the cause of your hard-hitting, go with the 10W and see how it works for you. Here's a thread discussing the Forza fork: http://www.hondapcx.org/viewtopic.php?f=2&t=1285
Scroll down to the quoted manual specs from Maddiedog. He gives an amount and type. Further down, there's a depth spec, as well.
As to how to change it? Maybe some else will chime in, but, generally, forks will have some sort of plug threaded into the bottom and the same or very similar at the top of the stanchions. I use a big syringe (20 or 30 cc) to fill them. I have a PCX manual, but I doubt it applies to your bike.
Anyone else?
davenowherejones
Frequent Poster
Frequent Poster
Posts: 1817
Joined: Sat Jun 20, 2015 12:06 pm
Year: 2014
Color: Silver
Location: Hope, BC, Canada

Re: Fork oil checking

Post by davenowherejones »

The bottom of the fork has a hex hole. Is that an adjuster or a drain?

The top of the fork seems smooth by touch. No big hex cap as far as I can feel. How do you get the oil in?

118 ml of oil is not much. Would 20 wt take my weight better or just make the fork slower to react?

Do I have to take the fork off the scooter to change oil?
glencoeman
Regular User
Regular User
Posts: 109
Joined: Thu Oct 02, 2014 10:53 am

Re: Fork oil checking

Post by glencoeman »

I would suggest that you buy a service manual for your Forza - available on the internet from the USA. The hex hole screw at the bottom of the fork leg should not be removed unless you are going to totally dismantle the internals of each fork leg as it can be very difficult to put the hex screws back in tight. You have to remove the front wheel and mudguard, disconnect the brake lines from the fork leg bottom. Then remove the top bolt at the top of the fork leg, then slacken off the bolt directly below it. Remove the fork leg and put it into a vice. At the top of the fork leg is a plastic cap which you remove. Then, with an extra pair of hands if you are not used to the process, you have to physically push down the centre of the fork leg (which is basically a large round spacer) where you will see a circlip ring which must be removed. After removal, the fork spring can be removed and the old fork oil emptied onto a container. Refill with 204cc (+ or - 2.5cc) of 10w fork oil in each fork leg. You can check the correct oil level by removing the spring and pushing the tube into the bottom of the fork leg . Measure the oil level from the top of the tube to the oil level and it should be 78mm (3.1 inches).
To rebuild, reverse the process.
The 118 ml figure that you saw was for a PC150 not a Forza 300.
davenowherejones
Frequent Poster
Frequent Poster
Posts: 1817
Joined: Sat Jun 20, 2015 12:06 pm
Year: 2014
Color: Silver
Location: Hope, BC, Canada

Re: Fork oil checking

Post by davenowherejones »

glencoeman wrote:I would suggest that you buy a service manual for your Forza - available on the internet from the USA. The hex hole screw at the bottom of the fork leg should not be removed unless you are going to totally dismantle the internals of each fork leg as it can be very difficult to put the hex screws back in tight. You have to remove the front wheel and mudguard, disconnect the brake lines from the fork leg bottom. Then remove the top bolt at the top of the fork leg, then slacken off the bolt directly below it. Remove the fork leg and put it into a vice. At the top of the fork leg is a plastic cap which you remove. Then, with an extra pair of hands if you are not used to the process, you have to physically push down the centre of the fork leg (which is basically a large round spacer) where you will see a circlip ring which must be removed. After removal, the fork spring can be removed and the old fork oil emptied onto a container. Refill with 204cc (+ or - 2.5cc) of 10w fork oil in each fork leg. You can check the correct oil level by removing the spring and pushing the tube into the bottom of the fork leg . Measure the oil level from the top of the tube to the oil level and it should be 78mm (3.1 inches).
To rebuild, reverse the process.
The 118 ml figure that you saw was for a PC150 not a Forza 300.
Thanks for the info, some forks have a drain and some don't.
davenowherejones
Frequent Poster
Frequent Poster
Posts: 1817
Joined: Sat Jun 20, 2015 12:06 pm
Year: 2014
Color: Silver
Location: Hope, BC, Canada

Re: Fork oil checking

Post by davenowherejones »

I am dyslexic and have had too many head injuries so I don't trust myself sometimes to work on motorcycles even though I have an ancient piece of paper somewhere which says I know one end of a wrench from the other.

I took the Forza to my dealer. They replaced the fork seals and added heavier oil.

It seems better but it did not suddenly make this into a dual sport on the bumps.
User avatar
gn2
Forum Benefactor
Forum Benefactor
Posts: 7767
Joined: Tue Dec 06, 2011 7:54 pm
Year: None
Location: NE Scotland

Re: Fork oil checking

Post by gn2 »

davenowherejones wrote:it did not suddenly make this into a dual sport on the bumps.
With 3.7 inches of front suspension travel it never will be.
You need to learn to ride around the bumps.
Four decades on two wheels has taught me nothing, all advice given is guaranteed to be wrong
davenowherejones
Frequent Poster
Frequent Poster
Posts: 1817
Joined: Sat Jun 20, 2015 12:06 pm
Year: 2014
Color: Silver
Location: Hope, BC, Canada

Re: Fork oil checking

Post by davenowherejones »

gn2 wrote:
davenowherejones wrote:it did not suddenly make this into a dual sport on the bumps.
With 3.7 inches of front suspension travel it never will be.
You need to learn to ride around the bumps.
Aw but my DR650 just goes over them.

Some of the bumps sneak up on me sometimes.

Is it really only 3.7 inches?

It is a good job I have a few extra inches of padding in my ass! I knew it would become useful somewhere.


500 km ride and it did not rain at all. Yay, Yay!!!
User avatar
gn2
Forum Benefactor
Forum Benefactor
Posts: 7767
Joined: Tue Dec 06, 2011 7:54 pm
Year: None
Location: NE Scotland

Re: Fork oil checking

Post by gn2 »

davenowherejones wrote:Is it really only 3.7 inches?
Yes and no.
Total travel is 3.7 inches.
Subtract from that whatever it sags by when you sit on it.
Four decades on two wheels has taught me nothing, all advice given is guaranteed to be wrong
davenowherejones
Frequent Poster
Frequent Poster
Posts: 1817
Joined: Sat Jun 20, 2015 12:06 pm
Year: 2014
Color: Silver
Location: Hope, BC, Canada

Re: Fork oil checking

Post by davenowherejones »

Old thread update.

At 10,000 km I took it to my dealer and had heavier oil put in. Not sure if there was any to start with. It fixed the problem.

I blew the seals at 52,000 km but that was after 42,000 of hard riding and a little mild off-roading.
aguim
Regular User
Regular User
Posts: 274
Joined: Sat Nov 05, 2016 2:03 pm
Year: Forza 300
Color: red/2014
Location: northern ontario

Re: Fork oil checking

Post by aguim »

@ 13Kkm, both mine's forks showed the factory oil capacity, plus it was surprisingly clean looking.
I used 10w BelRay as a replacement... couldn't see any difference. It still HATES potholes...
that's what small wheels/2.5 inch travel are all about.

The triple clamp bolts were torqued to the death, so were the axle nut and the lower fork axle-clamp
bolt. I put anti-seize everywhere and tightened them 'just enough'.

Hopefully it will make it to 40K before it needs new seals...
Post Reply