Suzuki SV650S - Throttle not closing fully?

[taybagger]

Hi guys, I'm a new rider and this is my first bike.

It's a 2004 Suzuki SV650S with 40k miles on it, I picked it up for £900.

I've had fun with it so far and it's been running fine, however, it's recently been pointed out to me that it's idling high. Since someone said it, I notice it all the time so I'm not riding it for now.

The Problem

When the bike is cold, I start it up, the RPMs go upto about 2k then quickly fall down to around 1.5k. Whilst cold, I can apply the throttle and the revs fall back down as expected.

As the bike heats up, if left untouched, the RPMs will stay at 1.5k.

If I start to apply throttle then release the throttle, the RPMs will remain at anywhere between 2k and 3.5k RPMs.

I've attached an image to the post. If I push this lever in the way a little, the RPMs will fall back down to 1.5k but anytime the throttle is opened and I let go, the RPMs don't fall.

Based on what I've read online, it could be a cable issue but I'm just not sure and wondered if anyone here could maybe shed some light?

(P.S: I know it's a bit rusy & quite nasty looking!)
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CBT - 29/09/16 | Theory - 07/11/16 | Mod 1 - 16/02/17 | Mod 2 - 23/02/17

First Bike - K4 Suzuki SV650 S

[tom_e]

My K5 has over 40k miles and looks brand new compared to that, I'd almost guarantee if the cam setup looks like that then your throttle cables are not at all healthy either.

Whip the airbox off and have a look at the state of the cables where they go into the TBs, it's just in front of that lever in the picture. While you're there soak that in ACF50. It's probably just sticking because it's dryer than a nuns fun parts.

[Tdibs]

Yup a healthy dose of lubricating oil all over that area if its not moving freely, could probably do with a good brushing too.
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Previous : 09 Vanvan 125| 02' Sv650s || Current: 1999 Xj600n | 1992 DR650 RSE | 2005 Fazer 1000

[taybagger]

@tom_e @Tdibs thanks guys.

Yeh it doesn't look healthy, I was hoping to get a year of fun out of it then move onto something newer. It's garage stored now and anything I can do to it to get a better clue I'll definitely look into.

Any idea why it only occurs when hot? Something heating up and expanding I assume?
____________________
CBT - 29/09/16 | Theory - 07/11/16 | Mod 1 - 16/02/17 | Mod 2 - 23/02/17

First Bike - K4 Suzuki SV650 S

[Robby]

It just be the idle set too high. That's the first place I'd look.

After that, likely causes are:
1. The throttle linkage is not moving smoothly. By the state of the linkage from that picture, this is quite likely. I would drown the area in WD40 whilst opening and closing the throttle.
2. The mixture screw settings and wildly wrong. This is usually because someone has played with them in the misguided belief that it will make the bike faster, or due to misdiagnosis of another fault. The screws will be on the carb near the engine end (usually). Their location and correct setting will be in the Haynes manual. Having these wide open or fully closed will make the bike cock around at tickover and very small throttle openings. Usual setting is around 2 turns out from fully screwed in.
3. Air leak, between the carbs and cylinder head. Usually because someone has been balancing the carbs and hasn't replaced the balancer hole covers, or they have had the carbs and not refitted them properly - either inlet rubber is folded at the carb and not making a seal, or the ring clamps holding the rubber onto the carb are loose.

Start at the top of the list and work your way down. Stop when the problem is fixed.

[taybagger]

[taybagger]

Ok, this will prove how dense I am with this stuff but need to learn somehow, so what the hell.

I'm pretty sure my bike is Fuel Injected, if so, this means it doesn't have carbs, right?

I'm confused as on some of the service history I have, one of the work items says "balance carbs"?
____________________
CBT - 29/09/16 | Theory - 07/11/16 | Mod 1 - 16/02/17 | Mod 2 - 23/02/17

First Bike - K4 Suzuki SV650 S

[tom_e]

Correct that bike is FI no carbs.

They may have gotten confused and meant balanced the throttle bodies.