93 ZXR400 fork oil weight?

[boostin]

Changing the oil in my track 93 ZXR400 front forks. I picked up some 10w Motul on Friday and changed the oil today in just one fork.

The return on the shock I have changed is a lot slower than the unchanged one. Doesn't seem to be any noticeable difference in compression rate.

I am not sure what weight oil is in the unchanged one but standard is 5w with 85mm air gap.

Just to add some more info into the mix I just checked the zxrworld.co.uk forums and the racers there seem to use 7.5w.

So my question is should I just change the other one to the 10w as well and give it a go, change it later if it doesn't work out, or would it be recommended to just go lighter weight now?

Thanks

[t3mp0r4ry nzr]

setting rebound is dependent on a number of variables, keen to see what the suspension pro's recommend.....

[boostin]

Yeah I am not specifically trying to tune the rebound but noticed it had changed significantly with the 'push down on the fork leg' test.

If it makes any difference to the recomendations I suspect most of the riding will be at Puke over summer maybe with a dabble at Hampton Downs.

[neil_cb125t]

hmmm this stuff can be i bit of a black art... have you changed spring rate?? are you using heavier oil to "stiffen" it up??

Simply out i would rebuild the other fork to what ever you have done - even if the other fork contains 10w it could be from 1993 when dino fossis were stil being found in oil!

Make them the same then adjust from there.

[boostin]

Thanks Neil.

Yeah I was trying to 'stiffen' them up a bit. Thinking about it now I spose I should have started with fresh 5w and gone up if I needed seeing as I have no idea when the last fork oil change was (ever?).

Any better brand of fork oil? I have seem RT reccomend Maxima. The local has Motul, Belray and I think they should be able to get Maxima in.

[Robert Taylor]

Thanks Neil.

Yeah I was trying to 'stiffen' them up a bit. Thinking about it now I spose I should have started with fresh 5w and gone up if I needed seeing as I have no idea when the last fork oil change was (ever?).

Any better brand of fork oil? I have seem RT reccomend Maxima. The local has Motul, Belray and I think they should be able to get Maxima in.

Heavier oil in cartridge forks will only ''stiffen up'' bypass bleed and have little effect when the shim stacks open.

[neil_cb125t]

Yeah is the normal track that people try, unfourtunately its a bit.... as rob has told me.... catching the horse after it had bolted.

The forks do work well if you can throw a set of heavier springs in it, thats all i have and what ever oil ohlins or Rob put it in them. The valving in them is very basic but can be moddified.

its all dependant on your riding style and weight. oh and that thing called $$$
i'm currently trying to save up to throw about $1500 into my front end...


Thanks Neil.

Yeah I was trying to 'stiffen' them up a bit. Thinking about it now I spose I should have started with fresh 5w and gone up if I needed seeing as I have no idea when the last fork oil change was (ever?).

Any better brand of fork oil? I have seem RT reccomend Maxima. The local has Motul, Belray and I think they should be able to get Maxima in.

[zx rider]

I'm pretty sure Kawasaki road bikes take KYB #1 fork oil, which is 5w in most other brands.
You used 10w so that would slow and stiffen the forks a lot.
The best thing to do is consult Mr Robert Taylor about this. He helped me set up my bike and on this subject he is a LEGEND. :yes:

[boostin]

Yeah I have now put it back to 5w. It seems to have fixed the slow rebound I was worried about, I think... :mellow:

[scracha]

Yeah I have now put it back to 5w. It seems to have fixed the slow rebound I was worried about, I think... :mellow:

You fixed the non working brakes on that thing yet? Gotta say I loved the ZXR motor but the front end on it was awful.


and shhh...it's a 1989

[boostin]

Hmmm working on the brakes, better but still squishy. Might rebuild the master cylinder and if that doesn't work might to the calipers, and if that doesn't work then who needs brakes?

Going out to Puke this weekend to check it all out.