Which Fork Oil best suited?

[Bibio]

personally i always thought that the rebound was the worst part of the stock forks. hence the pogo effect.

and here was me going to suggest welding up one of the rebound holes. ooohhh well you live and learn.

as to measuring the air gap just use a chopstick or something with a lines marked on it, dip stick in fork and pull out then see how much you are over or under the marks. or go and take out you cars dipstick (if its long enough) and use that.

Eh lol.

I'm completely lost when it comes to cause and effect on suspension!
More than usual! Iv read about it a few times but obviously not sinking in.

[Bibio]

if you have to much rebound (less reactive/hard) and you go over a lot of bumps the forks do not have enough time to return to 'state' so when you hit the next bump there is less travel in the forks so it compresses a bit more and so forth until it runs out of travel. but i could be wrong.

i used a long metal ruler to do mine

[yorkie_chris]

Originally Posted by Bibio

personally i always thought that the rebound was the worst part of the stock forks. hence the pogo effect.

and here was me going to suggest welding up one of the rebound holes. ooohhh well you live and learn.

as to measuring the air gap just use a chopstick or something with a lines marked on it, dip stick in fork and pull out then see how much you are over or under the marks. or go and take out you cars dipstick (if its long enough) and use that.

You can weld hole up if you want, there is only one rebound hole.

2 things at play, oil viscosity and size of bleed. There is lots of leakage so even with hole welded there is still flow. If you use say 20W with hole there, then you might be able to use 15W with hole welded up.

Yeah lack of rebound is bad with stock parts, but if you make rebound way too firm then it's worse!

Originally Posted by hongman

Can you elaborate on that bit, just for my intellectual benefit?

If you have too little rebound the front feels unstable, like it's pumping up and down even in smooth corner.

If you have too much rebound then it will (as bibio says) not recover from one little ripple to next and feel like it is making little jumps out wide in corner. Like understeer, very unnerving.

O eck, doesnt sound like I can really win either way, to find a nice middle ground for it all!

I bought some castrol 10w today, gonna bang it in tomorrow as long as I can find my rachet straps. Gotta be better than whats in there now.

[yorkie_chris]

There is plenty middle ground where the rebound is neither too fast or slow. Of course with cartridge fork it is easy to twiddle around to find this area.

That 10w is probably fine for stock springs.

Just went for 60 mile blast down some country roads and the bits I really want to sort are:

1. Diving on slowing/braking
2. Over bumpy roads its sooo juddery, like there's no suspension there. At some points I have to slow down becuase my vision is too shaky to see wtf is ahead of me.

3 times on that ride I was fully out of my seat, first the front then the back in the air. They were some pretty hench bumps though!

But arent those 2 symtpoms caused by opposites you descrbed above? Cant have too little AND too much rebound!

Ok, all done. Only took 1.5 hours, 30 mins of which was taking the fairings off and back on. I know I didnt need to but while waiting for my mate I thought it'd give better access etc.

Some things we noticed and were not sure about....

1. The oil that came out was a dark brown/red colour, but consistency didnt seem that much different to the new stuff. Didnt smell of anything.

2. The LH fork was a bit of a bastad to get the cap back on, took two of us to do it. One to hold the fork leg and the other pushing down really hard as we needed to compress the spring also. The RHS was really easy, cap just screwed on. It was like the LHS internals sat higher up?

One thing I will note is that I did not strip the forks completely, as my allen socket could not reach the damper rod bolt. Allen keys were useless, and I didnt want to risk rounding.

So just undid the cap, took all the bits out, sloshed round with paraffin and pumped it abuot to get all the crap out.

LHS fork while empty got stuck down fully compressed, and took a fair yank to free it up again. RHS exhibited no such behaviour.

So questions are:

Is there something wrong with the LHS, what with the components sitting higher up (past the cap thread) and getting stuck while empty and compressed?

Did I measure the air gap correctly? Had all the internals out, leg fully down, gap of 115mm as per haynes from top of fork.

Took it for a quick blat down the road, I wouldnt say its night and day difference but certainly a bit better - less diving on braking and deceleration. Wont know til I take it for a proper run.

Thanks.

[Bibio]

sounds like you have put one of the springs upside down (dont know if the curvy is tapered) or are missing a spring spacer. either way both the forks should be the same to put back and no difference in hight. so if you had to push one cap more than the other there is something wrong.