2006 sv1000sz lurching

[Niall_farley]

So I'll explain what's happening. Sat on the duel carriageway on the way to work earlier between 70-80 and its lurching as if I'm driving thru tar for a second or two then goes again then slows again.

This is while the throttle is held steady and the speedo isn't really showing any difference worth noting. If you where viewing me you probably wouldn't notice it unless you where on the bike itself. I've noticed it for a couple of weeks now but it's getting worst.

Any ideas what it could be? Always starts on the button? Even if left a week it'll start easy. Was serviced maybe 1000 miles ago I always keep it serviced

Hope you can all help. Cheers guys

[Swin]

I had a similar issue on a bike a few years ago, turned out to be a cylinder cutting out in the wet

[Niall_farley]

How did you resolve it swin?

[Swin]

Sorry - should have said that I had the HT leads replaced - I also had an old GS450 years ago where an HT leads insulation had rubbed through, so that as I picked up speed and the wind blew the cable against the side of the tank, it shorted and caused the bike to run on one cylinder too

[Niall_farley]

Thanks swin. New update a couple of hundred yards from my work when I was leaving yesterday it cut out waiting at a junction on idle, then a further 600 yards i was at a set of lights and it idled fine but as soon as I touched the throttle to set off it cut out again. This was all while it was warming up where it seems to run quite rough just yesterday as well.

I will check the HT leads when I get a chance but I imagine it's something else if it's cutting out on cold idle?

Any other ideas anyone? I'm hoping it's just HT leads but I'm never usually that lucky :p

[Corny Gizmo]

Were the plugs replaced at the last service? any kinks in the fuel line? Nice strong spark from the plugs?

couple of things I would check bud.

[Niall_farley]

Cheers corny :) I'll check them all out. Plugs wherent replaced actually but was only 4000 ago maybe I have a few kicking about so I'll replace anyway :)

[maviczap]

Were the plugs replaced at the last service? any kinks in the fuel line? Nice strong spark from the plugs?

couple of things I would check bud.

I'd also make sure that the fuel tap filter is clear of muck & debris. I know it hasn't got an actual tap, but there must be a filter where it leaves the tank

[DJ123]

So I'll explain what's happening. Sat on the duel carriageway on the way to work earlier between 70-80 and its lurching as if I'm driving thru tar for a second or two then goes again then slows again.

This is while the throttle is held steady and the speedo isn't really showing any difference worth noting. If you where viewing me you probably wouldn't notice it unless you where on the bike itself. I've noticed it for a couple of weeks now but it's getting worst.

Any ideas what it could be? Always starts on the button? Even if left a week it'll start easy. Was serviced maybe 1000 miles ago I always keep it serviced

Hope you can all help. Cheers guys

Check the TB's are properly sealed onto the inlet and also check the TB's are balanced.

[Mr Farley]

I had a similar problem on my old SV650, it was a crack in one of the HT leads. There was nothing visible to the naked eye, but that it what I was told by the garage. They replaced the lead and bike was fine again.

[Ratty]

Check the throttle position Sensor. SV1000S is sensitive to this. It likes a very precise setting and mine didn't like the setting described in the TPS pictorial on here. This setting gave the lurching you describe at 5K. My brother-in-laws SZ is also struggling with fuelling and I sorted it once. He since tried to refine it and ended up with it running shocking. I stripped off the sensor to check if it was worn inside, but ok. When I put it back together it ran fine again. Try setting it to middle bar at tick over rising to top bar at 2K. Make sure you use a good fitting Torx bit and replace screws with stainless Cap Heads if poss.

Hope this helps. Alan.