Stuttering SV3N

[MitchC]

Hello everyone!

I am hoping you fine SV aficionados can help me with my beloved SV3N... She's acting up again, must know winter is coming...

Last year I had some issues at the end of the season after I washed the bike before getting it ready to winterize, it wouldn't start. It died in the middle of an intersection and wouldn't start up again. I pushed it home and didn't deal with it till this spring. Changed the oil and she started up just fine this season. So I just assumed it was a combination of wet electrical, water in oil, etc.

Now, it starts up fine. Idles no problem, then by the time I ride for a couple minutes and come to a stop, it starts to act up. The revs drop below 1,000 rpm - ~500-600 -and it sounds like it's struggling for gas. I roll the throttle and it seems to help. I'll shift into first to take off from the light and have the clutch out, throttle open, nothing... It's getting some power but very little... Then after a few seconds it will "kick in" and it gets full power like normal. Gears 2 through 6 seem fine, high revs, fine. Just in first gear near idle. I've even had the bike stall while decelerating to a stop and the bike would just cut out once I shift down into 1st.

I've taken a couple videos to try and explain the situation. The first is really short, but it shows the idle drop, then the bike stall.

http://youtu.be/-dNqaFfb4jY?list=UUI...k2bqqMhb-HYFgg

The second video, I started the bike up again, it seemed to fun fine?

http://youtu.be/KQsggFojsuc?list=UUI...k2bqqMhb-HYFgg

I've had it do this for 5-10 minutes. I rode across the city, about 20 minutes averaging 60-100 kph. When I reached my destination, I just let the bike idle... No problems.

So the issue occurs near the start of a ride, once I ride constantly for a bit, it seems fine.

I don't know a lot about mechanical stuff... But I am leaning towards injectors or spark plug? Anything I can try to do to verify further?

Thanks for your help in advance!

Mitch

[Sid Squid]

I wouldn't be thinking either plug or injector initially, if it runs OK when hot it would appear they're not immediately suspect. That said, as with any not immediately obvious fault, it's always worth checking all the basics are right first, and of course that would include plug condition. If it were me, I would check it over as if it didn't run at all, assuming nothing were right, and see where led me.

[Bibio]

for a start why is your main beam light illuminated?

have you checked the tightness of the battery terminals?

i had a similar problem took it the garage.. what they told me they did to fix it was remove alarm, go over the electrics and clean and grease all the connectors, new sparks and replace tps. it hasn't done it since cants say for sure which one was causing it but mine was doing the exact same

[MitchC]

Originally Posted by Bibio

for a start why is your main beam light illuminated?

Because I have my high beams on?

Last night, went straight to the highway for about 20 minutes, slowed down after that, no issues. It's just the first little part of the ride it gets all sputtery.

I think I'll have to take it into the shop at the end of the season or beginning of next season to have them take a look at it.

Mitch

[MitchC]

So I took the bike into the dealership this spring, they tested the bike, reported no error codes. They decided to replace the battery (which was an off brand and a few years old, I bought it in a pinch when I was in University... Forgive me ) and issues seemed to be resolved. Yay!

However... The issue persists in a slightly different way... If I let the bike sit for a few days, it will fire up fine, idles around the normal 1,000-1,200 rpm. I can ride it out of my underground parkade, but once I ride a block and reach the first stop sign, it will sputter at low revs in first and second gear, idle will drop, as low as 800 rpm. I have to open the throttle to around 2,000 rpm in order to get fuel to the bike to prevent it from stalling.

But, if I take the bike straight to the highway, ride for 15-20 minutes, it seems to "flush out" the issue. It will ride fine after that. If I ride the bike again the next day, the bike will be fine. But if I park the bike for a week, the issue returns.

The air filter was clean. I decided to replace it anyways to see if that fixed the issue, which it didn't. I did replace it with an aftermarket K&N filter, but the issue occurred with the stock filter, as well. The inside pf the air box is clean. I am using 91+ octane fuel... I'm at a loss. And it becomes difficult to take to the dealership because they often can replicate the issue as by the time I ride it there, the issue has corrected itself.

Any advice or input you may have would be greatly appreciated!

Mitch

[Craig380]

I'd suspect an electrical glitch somewhere - a dodgy main earth where it bolts to the back of the gearbox, corrosion on the battery terminals / leads, battery connections not fully tightened with a 10mm wrench, that sort of thing.

Only takes 15 minutes to remove the battery leads and clean them with some fine grit paper, hose the earth points with contact cleaner etc

[Shawthing]

Firstly tickover could be set a little higher 1200-1300. Set it when engine at full running Temperature, and do the TPS setting while your at it.
http://forums.sv650.org/showthread.php?t=55459

If that doesnt cure then it sounds like one of the fuelling sensors e.g. engine coolant temp sensor or intake air temp sensor are adjusting the fuelling incorrectly.
This document could help:

http://www.sv650.info/download/serwi..._Diagnosis.pdf

[ophic]

or throttles could be out of balance, which can make tickover vary a lot between cold and hot.

So your tickover is kept up by the fast idle when you first start up, but once this cuts off it drops down very low until the bike warms up fully.

Just a thought.

[MitchC]

Thank you everyone for your comments. Here is a video of the sputtering I've been dealing with. This occurred when I was parked in my underground parkade, bringing the bike up to operating temperature.

https://youtu.be/BqOx-czV2-w

At any rate, I brought the bike up to operating temperature, 88° then adjusted the idle. Decided to go slightly higher than the 1,200 - 1,300 rpm recommended above. From there, I put the bike in "dealer mode" and adjusted the TPS sensor. (No error codes were present while in dealer mode, by the way).

Below, you'll see the -c didn't move up until about 3,800 rpm:

https://youtu.be/Dpom_nmzuHs

After the TPS sensor adjustment, the - c moved around 1,800 rpm:

https://youtu.be/nomDp6zsj-c

The bike is definitely more responsive since the adjustment, smoother at lower revs, but the issue still persists...

Mitch