Difficult down changes

Over my last few rides I have noticed that it has been difficult to travel down through the gearbox. The gear selector moves down, but it does not select the next gear. Sometimes I find that letting the clutch out, then pulling it in again helps, but this isn't always the case. I find that 3rd to 2nd is the worst for this. Any ideas what this might be?

Perhaps relevant info: Its been 3700 miles since I last changed the oil and filter, my chain and sprockets are getting on a bit, and I almost always clutchless gear change.

the first thing i would look at are the linkages, make sure they are not siezing up. it only takes a bit of stiffness there and the return spring cant do its job.
then the clutch ajustment. not sure if the SV has a cable or not meself though.
then try the oil change as that sometimes does the trick.
nothing wrong with clutchless changes but make sure you get it right changing down, thats the difficult one

Do you clutchless shift down the box? I understand that is not good practise, but clutchless up the box is ok to do, providing you know what your doing (i dont, I clutch all the time)

I suggest the following things:

Adjust the clutch worm drive

clean and lubricate the chain, and adjust to correct tension...or just replace if its worn (how many miles on that C&S set?)

This may help first.

Oil with 3700 miles of use shouldnt be giving rise to many gear selection problems, but if the above dosn't cure your problem, then change the oil and see how that goes. If the problem recures then you will need to delve further and inspect the clutch plates; clutchless shifting will probably cause more wear to the friction plates I beleive suzuki suggest 3500 mile oil change intervals anyway

See how imple cleaning and adjustment goes first

@rotax...SV clutches are cable operated and there is a worm-drive mechanism which converts the pull of the clutch lever into a push on the push rod

I only clutchless shift up the box, never down. I shall try the points suggested

Ok, cool just as a curiosity, do you have trouble getting into neutral at all?

errrm, not really no. seems to go in very easily, certainly better than my zxr did