Starting on single cylinder
 

sv650x has been in the garage since November. Have been doing bits and pieces of maintenance over winter but have always had trouble starting it. Thought it might just be the cold to start with but even with the weather a bit warmer it's the same.

It turns over fine but it seems like only the rear cylinder catches and every so often I get what feels like a little knock. It always starts eventually though if I rev it immediately it will stall. Once it's warmed up it seems absolutely fine.

Spark plugs have been replaced, oil has too and is about 2/3 between L and F, valve clearances are fine.

Am still waiting for a mod 2 date so can't take it out for a good blast yet, just wondering if there's anything obvious to try? I'd considered:

• Wait for license and see if a decent ride sorts it
• Balance carbs
• Check choke plungers
• Drain tank / Replace fuel

Re: Starting on single cylinder
 

I have similar symptoms on my pointy and from memory last time it was HT lead break down. I think I'm going to pick up some new leads and coils and seal them up before I fit them. Fed up with this problem every time it gets damp.

Interestingly I get this problem only when it's been stood in a garage that is damper than mine - seems very sensitive to humidity.

Re: Starting on single cylinder
 

I'd do the first two if I were you.

If you don't know the history of the bike and haven't got proof of any servicing it seems like the perfect time to do it.

I doubt the petrol will have gone off since November although the carbs may have gummed slightly.

Re: Starting on single cylinder
 

When I had my SV this used to happen if left for longer than a week or two. With mine bike would start up as normal then feel very bogged down, if I would tried to rev it, it would bog down further and stall. Also sounded like it was running on one cylinder at timess

Now one day the bike had it's MOT so I had to ride it as it was to try and get it there. Eventually after a bit of horrible riding it did clear up and with a few loud bangs it was back to full life! I believe its what monkey has said - carbs gummed up a bit from the fuel. My bike was restricted so obviously couldn't pull through any crap so it just sat in the carbs. I think this is what caused my problems and a few days in a row of driving / one very long drive would clear this up fine.

HTH

Re: Starting on single cylinder
 

I had a very similar sounding issue earlier this year. Was weak under heavy revs too. Managed to get it out on rides and would feel (a bit) better after a ride.

Fitted new air filter, new sparks and changed the oil but it was rebalancing the carbs that fixed it (had only been done 6-9 months -5kish miles ago), but could also be one or more of those issues you say. Also maybe worth checking all the connections to the air box - I can get similar symptoms on my curvy when it's not seated correctly or a pipe to the carbs works itself lose.

Adrian

Re: Starting on single cylinder
 

If the bike has done a lot of miles and you find it is probably the carbs that are gummed it might be worth removing, stripping, checking and cleaning them if you're up to it. While it might seem daunting if done methodically and carefully it is very satisfying.

Re: Starting on single cylinder
 

Also might be worth running some Redex (other fuel system cleaners are available!) through the system.