Intermittent starting problem, Curvy.

Hey guys, first time poster and it's a technical one! Hope someone can help.

I've been searching the forums and trying to gain some info to help me sort a starting issue on my 2000 650.

I am going to ask direct as my problem seems to be sporadic. The choke and cold start issue, I have it... Sometimes.

I am stuck in that position where it just won't start and the battery dies or fires straight up. Usually you have to keep your finger on the starter button and keep it firing until you can just gently open the choke a LITTLE leave it a few secs if it fires then turn the choke up slowly and hit a few revs into it. Other times it just plain refuses. Other times you can fire it straight up with the choke and it just works... What am I looking at repair wise here as the fact it has no pattern is throwing me off?

Getting ready to ride again this summer after a foot injury and the repair list seems to be getting longer and longer, a casualty of standing still for so long!

[Biker Biggles]

Battery fully charged and in good condition?The SV needs lots of leccy welly to start.
Choke plungers and cables all working and not sticking?Loads of posts on here about that.
Spark plugs clean and not too old and sh&gged out?
Carbs balanced?When was the bike last serviced?
Electrical connections.Battery terminals and connector boxes all can do with a clean and tighten up,as can the earths to frame and engine.
Theres a few suggestions to be looking at

[yorkie_chris]

Repair wise, sounds like it just needs a good fettling.

Hi guys,

Brand new battery, less than two weeks old, treated with a battery conditioner.
Hasn't had an oil change since last spring, but had new sparks in the summer.
It's had a new choke cable and is smooth in action. Pots not sure...

Electrical connections are sound, I know that every nut, screw and bolt has been tightened on the bike and I have had all fairings off and just sprayed and fitted two lower fairings. I've been quite anal about all that...

I can only assume it's fully choke related, but the lack of pattern makes me think otherwise. On top of that I don't really know what I am doing, even with the manual. Is it fairly straight forward to sort out the pots and cable?

Oh, forgot to mention that it backfires from time to time when you do get it started. Only if you rev it though, and not your normal 'slow down popping'

[Biker Biggles]

Choke plungers should be a regular maintenance thing on older curvys just to prevent trouble.Backfiring could be an airleak.Are the carbs and airbox seated properly,and are all the vacuum and breather pipes all connected?If the new battery is suspect so soon check the charging system with a multimeter.If that is playing up it will destroy the battery very quickly.

[yorkie_chris]

Could be a lean miss. If it's ever been left stood for a while there may be a bit of varnish in the idle circuits. That would explain it as a lean problem becomes less obvious when hot.

Like I say, bit of a fettle. Clean the carbs out, balance them up. Job should be a good un.

[embee]

Not teaching gran to suck eggs I hope, but FWIW...

I've always found from cold, use full choke and DO NOT TOUCH THE THROTTLE.
Use a short prod on the starter, a couple of seconds only. Then wait a few seconds for the fuel pump to deliver fuel as required. It's a vacuum spring loaded pump, the first few turns of the engine will pull the pump diaphragm which will then deliver fuel if you wait, no point cranking it over during this time.
Another short prod and it should fire, it might then stall again, but another prod and it should fire and run. DO NOT TOUCH THE THOTTLE when the choke is on. If you do it usually upsets it and it can become a pig to start.
As soon as it's up and running ease the choke back as much as you can as soon as you can while keeping it running smoothly. Don't blip the throttle, it can provoke plug fouling.

As an aside, check all the connections including all the fuses not forgetting the main fuse in the starter relay (green plastic thing behind right black triangle below seat). Use some dielectric grease, or vaseline, or ACF50 on the blades to keep corrosion at bay.

Once it's been running for a short while then it should start with no choke but then use just a little throttle.