Fork Oil Level

[kingpenda]

Hi, How critical is the oil level in the forks? Haynes manual gives 123mm or 466cc, both very precise measurements.
My problem is this:- I drained the forks and then discovered that the gaiters prevent the forks being fully compressed for the measurement method to be used and as there is an unknown quantity of the old oil still in the bottom of the legs which can not be drained I can't accurately use the volume method either. I've added around 420cc to each leg and the forks seems to be damped but I'd like to know if there could be any dire consequences caused by too much or too little oil.
I'm reluctant to remove the legs if it can be avoided.

[numpty]

Too much oil and you`ll blow your fork seals, too little and you`ll have no damping, and either way you`ll upset the handling enough that you might as well be riding a shopping trolley!
As you`ve no way of knowing the amount of oil left in them, you have no way of knowing how much to add. The measurement of 123mm for oil level has to be made with the forks fully compressed, so sorry to be the bearer of bad news, but your only option to get the oil level right is to remove the forks. On the bright side, it`s one of those rare occasions where you have the perfect opportunity to give everything a proper check and clean.

[kingpenda]

Thanks for that Numpty, you've really made my day.   I'm going to have to bite the bullet and just do it, and as my granny always said 'Its better to be safe than sorry'.

[ploddit]

I had mine off to do it, I found 15 too hard on my bumpy roads, Honda say ATF which is about 7,5W so I try 10 whenever my new guides arrive.

[pikey]

The stock Showa`s lower legs are cast with a boss in them that on the Bros has a drain screw (M5) fitted. If you centre punch the boss and drill it carefully to tapping size of 4.2 mm, for the coarse, NOT fine M5 thread,you`ll have the ability to drain your fork oil without inverting the forks. Once tapped out, a suitable stainless cap headed screw and a rubber faced washer or even fibre or annealed copper, aluminium etc washer can be fitted.It`s very simple to do.

en.wikipedia.org/wiki/ISO_metric_screw_thread

By the way, if you drill them with light pressure on the forks(use a ratchet strap), as the 4.2 mm drill breaks through the resulting rush of ATF / fork oil will stop any alloy swarf from entering the fork leg. It will however cover YOU in oil. But hey, it washes off.

[Buzzin (^_^)]

I'm pretty sure my revere 650 had a drainbolt too.
I am certain I didn't drill anything out, but it took some effect to get it loose as your suppose to do it with the spring still under tension (oops...always read the entire instructions BEFORE you begin...)

[seastate]

Thats the securing bolt right in the middle that you need to get the spindle off to access? There's a 'proper' drain on the back inside of them and all my NTV's have had them but I've always found it easier to whip them off whenever I wanted to change the viscosity of the fork oil