Honda-SOHC

SOHC.co.uk Forums => CB750 => Topic started by: PMK on July 26, 2010, 10:13:54 AM

Title: Fork oil
Post by: PMK on July 26, 2010, 10:13:54 AM

Right then, I have a fork seal to do on the F2

I know an oil thread is always asking for trouble but what grade should I use?

(ducks for cover)

Title: Re: Fork oil
Post by: Bryanj on July 26, 2010, 01:42:26 PM

Use a proper fork all in both legs, F2 with two riders SAE30 just you SAE20.

Decenr fork oils wern't about when the books were written for these but are far better than any other straight or mixed batch that used to be used.

As you have to take all the mudguard, wheel etc off to do one I would do both. There is a "Fix" for pitted stanchions it you need it PM me and i will explain it

Title: Re: Fork oil
Post by: Seamus on July 26, 2010, 02:04:18 PM

Apologies for a Slight hijack on the fork seals thought. I have a new set to fit (early K2 forks) and the existing ones are different (thicker) I believe these to be aftermarket as the spacer is no longer present. Anyone know the dimensions of the spacer so I can get a couple made?
These are no longer available.

Thanks

Seamus

Title: Re: Fork oil
Post by: PMK on July 26, 2010, 05:37:40 PM

Thanks for that BryanJ

Much appreciated

Title: Re: Fork oil
Post by: BigAl (Alan) on July 26, 2010, 06:07:21 PM

I've used Castrol (fork oil) SAE 10w...the Hayes manual recommends SAE 10-30 for the K0-K6

Alan

Title: Re: Fork oil
Post by: K2-K6 on July 26, 2010, 09:04:42 PM

SAE 30 is about the pactical max before they start feeling harsh so take your pick. Think all the brands are quite good now but always used Bel-Ray in moto-cross as it stayed good during high demand / heat, but also like Motul.

It's good to have a bit of drop as you roll off the throttle for a corner as the head angle tightens on compression or else the steering feels even slower. I find if you go much over 20sae that starts to slow down noticeably and the steering start too feel odd:- forks go down slower so you feel initially that you have to turn it harder then compression peaks later and you start "thrupenny bitting", if that makes any sense.

Plus too high SAE and it starts to stutter on bumps as the bike rather than the forks move up.

Title: Re: Fork oil
Post by: sim2011 on July 29, 2010, 06:21:02 PM

I'm using Fuchs Silkolene SAE 10 in my 750K3 , it should be back on the road tommorow so I'll let you know what it behaves like.

Title: Re: Fork oil
Post by: PMK on July 29, 2010, 06:43:01 PM

I got 4 x 1 litre bottles of Morris 20W for a good price from good old ebay.

So I'll use that and see what happens

Do we want a fork strip by numbers article?