SVS does not rev - SV650.org

12-11-07, 08:10 PM

Hello there, newbie with a problem here. I've had my SV650S ('99) for a few months and it's been good as gold up 'til now. I had covered about 85 miles of my 88 mile journey tonight (fortunately!), pulled away from the lights in first, second, third, all okay, then into fourth and she lost almost all power. I juddered my way home, backfiring when the throttle closed. Thought it might be icing, but I waited an hour or so for the carbs to warm up and it's as bad as ever. Idle is fine, but then struggles as soon as the throttle is opened

. Any ideas veterans? I'm stumped.

12-11-07, 08:24 PM

Do you have a fender extender?
Was it wet today?

Biker Biggles · 12-11-07, 08:33 PM

Check the airbox is seated on the carbs ok with no leaks,and also there is a bit of foam glued under the fuel tank.Check it has not come off and blocked the air filter intake.Then check fuel hoses for kinks and holes,and that the vacuum hose to the fuel tap is connected ok.
Also could be sticking choke plungers or cable,crap fuel or water getting in somewhere it shouldnt.

Biker Biggles · 12-11-07, 08:33 PM

Check the airbox is seated on the carbs ok with no leaks,and also there is a bit of foam glued under the fuel tank.Check it has not come off and blocked the air filter intake.Then check fuel hoses for kinks and holes,and that the vacuum hose to the fuel tap is connected ok.
Also could be sticking choke plungers or cable,crap fuel or water getting in somewhere it shouldnt.

12-11-07, 08:37 PM

You just had a reply from Fred Elliot masquerading as Biker Biggles.

Biker Biggles · 12-11-07, 08:42 PM

I talk so much crap I need to say it all twice.

Isaid.

I talk so OH never mind.

12-11-07, 09:02 PM

Razor: Cheers, but I have a fenda extenda, and it's dry out. Would be an easy fix though

Biker biggles: Thanks for the help, I'll have a go at that lot tomorrow. Wish me luck...

12-11-07, 09:33 PM

Your carbs may have misteriously fallen out of sync... Means you need to make them so that the butterflies are open the same amount for a given throttle position. A pair of pressure guages may be needed though you can adjust it by ear. Just keep adjusting the screw that ballences them till it runs better...

Also there might be a problem with the fuel if it hasn't been run for a while! I had an old VT that was stood for a long time. Basically you might know but the fuel goes off, gets a lot like mud or jelly. When the tank gets a little empty then this can be pulled into the carbs a blocks them all up (or it might have gone off in the carbs...) this means youll need to strip them down and clean out the jets! Not a great job but if i needs doing it needs doing!

The fuel going off sounds the best explanation imo...

Hope that helps!

12-11-07, 09:45 PM

Cheers, thinking about it, the tank was unusually empty when I filled it yesterday. I usually fill it when the light starts to flash, but it was steady on yesterday.

13-11-07, 01:32 AM

let us know if cleaning the carbs helps (if you decide to go for that of course).

12-11-07, 08:10 PM	#1
clacs2 Guest Posts: n/a	SVS does not rev Hello there, newbie with a problem here. I've had my SV650S ('99) for a few months and it's been good as gold up 'til now. I had covered about 85 miles of my 88 mile journey tonight (fortunately!), pulled away from the lights in first, second, third, all okay, then into fourth and she lost almost all power. I juddered my way home, backfiring when the throttle closed. Thought it might be icing, but I waited an hour or so for the carbs to warm up and it's as bad as ever. Idle is fine, but then struggles as soon as the throttle is opened . Any ideas veterans? I'm stumped.

12-11-07, 08:24 PM	#2
Razor Guest Posts: n/a	Re: SVS does not rev Do you have a fender extender? Was it wet today?

12-11-07, 08:33 PM	#3
Biker Biggles Member Mega Poster Join Date: Jan 2005 Location: Barnet Herts Posts: 5,071	Re: SVS does not rev Check the airbox is seated on the carbs ok with no leaks,and also there is a bit of foam glued under the fuel tank.Check it has not come off and blocked the air filter intake.Then check fuel hoses for kinks and holes,and that the vacuum hose to the fuel tap is connected ok. Also could be sticking choke plungers or cable,crap fuel or water getting in somewhere it shouldnt. __________________ On a clear day we stand there and look further than the ordinary eye can see.

12-11-07, 08:33 PM	#4
Biker Biggles Member Mega Poster Join Date: Jan 2005 Location: Barnet Herts Posts: 5,071	Re: SVS does not rev Check the airbox is seated on the carbs ok with no leaks,and also there is a bit of foam glued under the fuel tank.Check it has not come off and blocked the air filter intake.Then check fuel hoses for kinks and holes,and that the vacuum hose to the fuel tap is connected ok. Also could be sticking choke plungers or cable,crap fuel or water getting in somewhere it shouldnt. __________________ On a clear day we stand there and look further than the ordinary eye can see.

12-11-07, 08:37 PM	#5
Pedrosa Guest Posts: n/a	Re: SVS does not rev You just had a reply from Fred Elliot masquerading as Biker Biggles.

12-11-07, 08:42 PM	#6
Biker Biggles Member Mega Poster Join Date: Jan 2005 Location: Barnet Herts Posts: 5,071	Re: SVS does not rev I talk so much crap I need to say it all twice. Isaid. I talk so OH never mind. __________________ On a clear day we stand there and look further than the ordinary eye can see.

12-11-07, 09:02 PM	#7
clacs2 Guest Posts: n/a	Re: SVS does not rev Razor: Cheers, but I have a fenda extenda, and it's dry out. Would be an easy fix though Biker biggles: Thanks for the help, I'll have a go at that lot tomorrow. Wish me luck...

12-11-07, 09:33 PM	#8
ThEGr33k Guest Posts: n/a	Re: SVS does not rev Your carbs may have misteriously fallen out of sync... Means you need to make them so that the butterflies are open the same amount for a given throttle position. A pair of pressure guages may be needed though you can adjust it by ear. Just keep adjusting the screw that ballences them till it runs better... Also there might be a problem with the fuel if it hasn't been run for a while! I had an old VT that was stood for a long time. Basically you might know but the fuel goes off, gets a lot like mud or jelly. When the tank gets a little empty then this can be pulled into the carbs a blocks them all up (or it might have gone off in the carbs...) this means youll need to strip them down and clean out the jets! Not a great job but if i needs doing it needs doing! The fuel going off sounds the best explanation imo... Hope that helps!

12-11-07, 09:45 PM	#9
clacs2 Guest Posts: n/a	Re: SVS does not rev Cheers, thinking about it, the tank was unusually empty when I filled it yesterday. I usually fill it when the light starts to flash, but it was steady on yesterday.

13-11-07, 01:32 AM	#10
ThEGr33k Guest Posts: n/a	Re: SVS does not rev let us know if cleaning the carbs helps (if you decide to go for that of course).