Intermittent Power Loss

Hello guys and gals,

Ok, so I have a SV650s 1999 with 19k miles on it, well serviced etc.

2-3 months ago I started suffering from Carb-Icing, which I would have to stop at least once on the way to work. Since the weather has warmed up slightly, it has gone away but a new problem has come about.

The problem:

The bike feels guttless, a bit like when I had it restricted, wooley acceleration. There is no back-firing. I can still hit 100+mph but takes a while to get there. It varies in amount of power loss, sometimes a slight decrease mid rev range, sometimes entire rev range large loss.

Possible Causes:

I have noticed that the problem is more severe in heavy rain suggesting its water getting in some where, bit it has also happened in dry conditions too (but not quite as bad)

I have checked:

Drainage pipe on fuel tank, had spark plugs replaced, carbs cleaned, bike running whilst spraying water on different electrical areas. And finally last weekend cleaned the front plug and put grease around it.

Conclusion:

I AM AT MY WITS END!!! My bike is still more than usable etc but its very frustrating.

Please please please help me out,

Kind Regards,

Luke

[Biker Biggles]

Take the plugs out and inspect them.You may find one of the choke plungers is sticking,causing a rich mixture on one of the cylinders.Not enough to stop the bike but enough to cause a power drop.

Thank you for your reply.

As I mentioned before, I have had both the sparks replaced (whilst trying to remedy the problem) which didn't make a difference.

With regards to the Choke Plungers, I'm not sure where to look (and I'm at work atm), whats a good way to see if they are sticking and what do you suggest I do to stop them from sticking?

Regards,

Luke

EDIT: Sorry, I forgot to mention that when I first start my bike up and ride, there isn't any power loss, only after 5-10mins or riding in the wet, or longer if its dry. Could this be heat related or a coincidence?

its sticking choke plungers. when engines are cold they need a richer mixture to run properly (ever shut the choke off to early and have it cut out?) when the engine gets warm it no longer needs the rich mixture, however it sounds like its getting it, hence the power loss. what colour were the plugs?

Nice to know it aint just me with this problem, someone suggested getting some 3 in 1 oil spray that down the choke cable and that should sort the problem of a sticky plunger. Dont know if its worked yet as I aint been on a half decent run but fingers crossed.