Topic: Fork oil level in CB650Z forks?

[Jimcg]

After taking the forks apart, painting lower legs and having installed new seals and dust covers I gladly filled the forks with Motorex fork oil and didn't bother to measure how much because I was going to measure the correct level. But after looking thorugh the Haynes manual and searching here, all I can find is level measurements (120-140 mm) for CB750's.

Does anyone know a good level to start with in '82 CB650Z forks (not Custom/Nighthawk)? I set it at 135 mm now and figure I could test drive (assuming there's not much difference to a 750 fork leg) but it's always better to know. Of course I can drain and refill a specific amount, but asking first seemed easier.

/Jim

[flatlander]

i don't know for the 650, and the old honda manuals give total volume instead of level from top.
in a recent discussion on the 550, the consensus was on an oil level from top of 140 - 160mm. you're probably not that far off and can test ride it, then fine tune it to your needs and liking.

[Jimcg]

i don't know for the 650, and the old honda manuals give total volume instead of level from top.
in a recent discussion on the 550, the consensus was on an oil level from top of 140 - 160mm. you're probably not that far off and can test ride it, then fine tune it to your needs and liking.

Thanks, I'll wait and see how it feels then. Bought a sort of collar that I planned to cut in different sized (thickness wise) "washers" as a preload fine tune but since I might have overfilled the forks slightly I'll wait until I know if I'll need it.

/Jim

[caluser2000]

Let us know how you get on Jim. The info will be useful to other 650Z owners here I'm sure.

[fizzlebottom]

I'm unsure of the specs for the 82 CB650Z, but here's what my FSM says for the regular 82 CB650 & CB650SC:

CB650
Front fork oil capacity (Dry): 210cc or 7.1oz
Front fork oil capacity (After draining: 190cc or 6.5oz

CB650SC
Front fork oil capacity (Dry): 320cc or 10.8oz
Front fork oil capacity (After draining): 300cc or 10.2oz

So depending on which one yours is based on, use the appropriate numbers. I'm curious about your front brake setup: single or dual rotor? And are your forks air assisted? Pics would help, as I'm pretty unfamiliar with the CB650Z

[caluser2000]

My little bro had a CB650Z and he love riding it. Gave riders with larger capacity m/cs a tun for there money, especially when the roads got narrower and twistier.

At the time I went for a 650 custom. Bad choice on my part. Wrong bike for the type of riding we did. 650Z was a far more stable platform and I should have got looking back now.

[Jimcg]

I'm unsure of the specs for the 82 CB650Z, but here's what my FSM says for the regular 82 CB650 & CB650SC:

CB650
Front fork oil capacity (Dry): 210cc or 7.1oz
Front fork oil capacity (After draining: 190cc or 6.5oz

CB650SC
Front fork oil capacity (Dry): 320cc or 10.8oz
Front fork oil capacity (After draining): 300cc or 10.2oz

So depending on which one yours is based on, use the appropriate numbers. I'm curious about your front brake setup: single or dual rotor? And are your forks air assisted? Pics would help, as I'm pretty unfamiliar with the CB650Z

Thanks for your answer. Pics of my bike are in the thread linked in my signature.

I have the volume specs in my manual but was looking for the level measurement - another way to verify correct amount of oil in the forks. Several threads here about that method but none of them about the 650 and when the 650 comes up it's mostly the SC/Custom/Nighthawk, not the standard version.

Let us know how you get on Jim. The info will be useful to other 650Z owners here I'm sure.

I will! I'll try the way I filled them up now, no springs mounted and forks fully compressed standing vertical, filled to 135 mm from top. We'll see how it turns out. I report back once it's been on the road for a while.

/Jim

[fizzlebottom]

The only other way I saw fork oil measured in the FSM was for the 81' CB650, in which it says to "Extend the inner tube all the way. Pour ATF into the fork tube up to the bottom of the cap threads and install the fork tube cap."