SV650 K5 - which suspension oil?

Hi All,

time to change my sv650 oil. I have never done this before.

is it the same oil as the engine oil ?

I have seen forum mentioning 5w for light weight and 10w-15w for heavy

please suggest .

If my suspension has a soft spring and I use 15w which reduce dampening is that the same as having stiffer spring ?

i am 110kg and plan to use my bike in track days only

The reason for not changing the spring is I don't know what type of spring rate I have .

I am thinking of taking it off first and then testing to find out its rate

[jambo]

If you weigh 110kg, it's a fair bet that the standard springs will be on the soft side.

Work out what spring rate you're after using something like the racetech calculator: http://racetech.com/ChooseVehicle.aspx (you don't mention the year for bike you have, but the spring rate will be similar in either case).

Get the spring right first, and for something that stiff, on track I'd probably start with a 15w and see if that was too choppy or not.

Spring rate will affect how far the suspension travels for a given load. Fork oil viscosity will affect the rate that the forks bounce back up after being compressed (standard forks have very little compression damping, you can look at emulators if you want to change this).

Jambo

thanks

my bike is 05 model

the previous owner has installed braided brake lines and crash protectors plus some other race modes so thought he should have changed the spring but that is dependent on his weight . if he was 50-60 kg then I have a wrong spring in there.

I am going to take the spring out, is it a difficult task ?

re oil is it the same engine oil that everyone uses ? or specific fork oil ?

[JulesW]

You'll need oil specific to forks i.e. Fork Oil

[jambo]

Originally Posted by stranger12

thanks
I am going to take the spring out, is it a difficult task ?

Not really. Get the weight off the front end (NWS/Abba stand and a jack at the front / tie downs at the rear or similar). Undo the top yoke clamps where they grip the top of the fork, then undo the fork cap itself. Pull out the spacers & springs. If you've got after-market ones sometimes they have the rate etched onto one end. Depends who made them.

Originally Posted by stranger12

re oil is it the same engine oil that everyone uses ? or specific fork oil ?

As above, it's a specific fork oil. And different manufacturers class weights differently, there's a table here that's worth a quick glance. Don't get too hung up on it, just appriciate that if you want to change oils around for feel it's best to stick with one brand where possible as some 10w are thicker than other's 15w. This can get very confusing if you move from a 10w to a 15w and it feels the same

Jambo

many thanks