mis fire help with cylinders please

[tylerb123]

hi guys random question should both cylinders run by itself without the other on sv650 1999 so if front is plugged in and the rear is out. the front keeps bike running but with front unplugged and rear connected it dies straight away.

i seem to either have a misfire or carb issue but im not sure i have checked plugs leads and coils but not sure what to do any help would be great thank you

[garynortheast]

Pull the rear cap off and put a spark plug in it to make sure you have a spark at the rear.

How old are the plugs, how old is the fuel in the bike, has the bike been stood unused for any length of time?

Welcome along to the forum, by the way.

[tylerb123]

Originally Posted by garynortheast

Pull the rear cap off and put a spark plug in it to make sure you have a spark at the rear.

How old are the plugs, how old is the fuel in the bike, has the bike been stood unused for any length of time?

Welcome along to the forum, by the way.

hi thank you for replying

there is spark at the rear ive checked this.

plugs are only 3-4 months old the fuel is new it was stood for roughly a month fuel is new but was only about about 3-4 litres in there but i took off fuel tank and emptied it but must of been stuff still in carb. who knows

[Seeker]

I'd suspect a plugged pilot jet on the rear carb assuming the airscrews are set to 2.5 turns out (and the choke plunger hasn't stuck).

Don't forget that carb screws are JIS heads (and seem soft).

Incidentally, there are a lot of fake NGK plugs on ebay, so many that NGK have published a bulletin http://www.ngk-sparkplugs.jp/english...ake/index.html

... and hello, btw.

[R1ffR4ff]

Originally Posted by tylerb123

hi thank you for replying

there is spark at the rear ive checked this.

plugs are only 3-4 months old the fuel is new it was stood for roughly a month fuel is new but was only about about 3-4 litres in there but i took off fuel tank and emptied it but must of been stuff still in carb. who knows

Also try swapping the Spark plug caps.If the fault follows you know one if faulty.

The OEM ones are very expensive so I use NGK straights,

Red or black,

https://www.ebay.co.uk/itm/Suzuki-SV...8AAOSwXMZaX~fv

https://www.ebay.co.uk/itm/Suzuki-SV...sAAOSwExlaYlft

[garynortheast]

I suspect R1ffR4ff just forgot to say this, but slosh a good dose of Redex into the next tankful of fuel too.

[R1ffR4ff]

Originally Posted by garynortheast

I suspect R1ffR4ff just forgot to say this, but slosh a good dose of Redex into the next tankful of fuel too.

Good idea

There's a very happy Lawnmower around here somewhere<grin>