Surgin on steady throttle - SV650.org

06-06-06, 08:27 PM

Hello, I was wondering if anyone could help.

I have a 1999 SV650S with about 14k on the clock, the original one with carbs, it's all pretty much standard apart from some braided brake hoses.

It seems to be running rough, at a constant throttle it surges, it's like the revs are hunting around, not a massive amount and it hardly notices above 40 mph/or so , the speed doesn't really change it just feels like a small slow regular stutter.

It doesn't seem to be mis firing and it has recently had the carbs balanced and plugs replaced as part of a service which improved things but did not completely eradicate the problem, the problem started before the service. Performance seems to be fine, very good in fact, and at speed I don't really notice the surge only at lower speed, at 30 keeping it in a low gear seems to help.
I don't think there's any water in the fuel as I have read that can be an issue.

Anyone got any ideas, I'd rather not go through the aggro of taking it back to the shop where it was serviced.

Does anyone think that an ageing battery could cause this as I get the feeling mine is on it's way out, or any other suggestions would be appreciated.

Cheers
Robert

Sid Squid · 06-06-06, 10:26 PM

For poor running check everything that would ordinarily cause no running, it can be anything. In this circumstance it's likely that carb balance is off, but bear in mind that balance is the job done last as it's affected by all other factors, plugs, clearances etc.

06-06-06, 10:55 PM

Might sound stupid but could it be your chain? Mine just that cos the chain's just about dead...

06-06-06, 11:17 PM

What gear are you in?.....................40 in 5th or 6th might cause a surge

06-06-06, 11:26 PM

Quote:

Originally Posted by svrash

What gear are you in?.....................40 in 5th or 6th might cause a surge

leathers and helmet !!

couldnt resist..

07-06-06, 11:45 AM

Cheers for the responses, it could be the chain then as it is the original and getting pretty old, but it doesn't feel like it's the chain.
I'm not to sure which gear I'm in, and it seems a higher gear is better, but I'm certainly not in 5/6th. If I have the revs around 3/4k the problem doesn't seem so bad as when the revs are 5/6/7, again this is only noticeable at speeds below 40.
I think I'm going to try and new battery first.

07-06-06, 12:51 PM

Mine is doing exactly the same thing as yours, although i know mine isn't the chain cause when idling the rev counter is bouncing around. Took it to the garage yesterday after checking all the vacuum pipes, fuel pipes etc They can't fit me in for another week but i did speak to the machanic there and he said try draining the carbs to see if there is water in them by unscrewing the drain plug and letting it drain into a jar or something. I looked in the Haynes and have located the drain plugs..... is it as simple as that ? I don't want to undo the drain plugs and petrol start pouring everywhere !!!

TSM · 07-06-06, 12:57 PM

I had a similer thing and it happened to be that the choke was still on a tad, not much but enough to make it happen.

07-06-06, 01:03 PM

Hey TSM. You know what.... think you may have hit the nail on the old head there. Mine is sticking a little...and i stress a little, even when in the off position.... how did you sort it ? Or was yours still in the on position when ya realised ? Ive oiled mine the best i can without stripping it down.

TSM · 07-06-06, 01:05 PM

Quote:

Originally Posted by ash

Hey TSM. You know what.... think you may have hit the nail on the old head there. Mine is sticking a little...and i stress a little, even when in the off position.... how did you sort it ? Or was yours still in the on position when ya realised ? Ive oiled mine the best i can without stripping it down.

Naa, i had just not pushed it all the way back. Once noticed it was sorted imediatly using my left hand. Quick push and it was sorted. Mabey you need to strip yours down including the plungers, i dont know though.

06-06-06, 08:27 PM	#1
rwball Guest Posts: n/a	Surgin on steady throttle Hello, I was wondering if anyone could help. I have a 1999 SV650S with about 14k on the clock, the original one with carbs, it's all pretty much standard apart from some braided brake hoses. It seems to be running rough, at a constant throttle it surges, it's like the revs are hunting around, not a massive amount and it hardly notices above 40 mph/or so , the speed doesn't really change it just feels like a small slow regular stutter. It doesn't seem to be mis firing and it has recently had the carbs balanced and plugs replaced as part of a service which improved things but did not completely eradicate the problem, the problem started before the service. Performance seems to be fine, very good in fact, and at speed I don't really notice the surge only at lower speed, at 30 keeping it in a low gear seems to help. I don't think there's any water in the fuel as I have read that can be an issue. Anyone got any ideas, I'd rather not go through the aggro of taking it back to the shop where it was serviced. Does anyone think that an ageing battery could cause this as I get the feeling mine is on it's way out, or any other suggestions would be appreciated. Cheers Robert

06-06-06, 10:26 PM	#2
Sid Squid No, I don't lend tools. Mega Poster Join Date: Jul 2003 Location: Skunk Works, Nth London Posts: 8,680	For poor running check everything that would ordinarily cause no running, it can be anything. In this circumstance it's likely that carb balance is off, but bear in mind that balance is the job done last as it's affected by all other factors, plugs, clearances etc. __________________ If an SV650 has a flat tyre in the forest and no-one is there to blow it up, how long will it be 'til someone posts that the reg/rec is duff and the world will end unless a CBR unit is fitted? A little bit of knowledge = a dangerous thing. "a deathless anthem of nuclear-strength romantic angst"

07-06-06, 12:57 PM	#8
TSM The Sick Man Mega Poster Join Date: Nov 2004 Location: Peckham.SE.LDN Posts: 4,768	I had a similer thing and it happened to be that the choke was still on a tad, not much but enough to make it happen. __________________ OTR: KTM 690 Duke R 2015 Full Akro SIDELINE: Kwak ZX636 A1P 2002, Red, R&G's, Yoshi, Double Bubble Screen GONE: Kwak ZX-7R P1, Full Akro, Undertray, Screen GONE: SV650S K2 Very Bruised & Without Fairing, Motovation Frame Sliders, R&G Ally Sprocket Toe Protector, HEL 2 Line Setup, GSXR K1 600 RWU Forks, Barnett Clutch & Springs, Penske 8981 Shock, Gilles Ti Rearsets, Steel Barends, Scottoiler, AFAM Chain & Sprockets, Twin FIAMM Horns, Skidmarx Bellypan, Full Micron Zeta Steel System, Cut down undertay. Forum Problems & Information / Site Suggestions

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
r6 throttle mod where has it gone?	ianofbhills	SV Talk, Tuning & Tweaking	12	12-07-09 09:04 AM
stutter on steady throttle FI	mikey devon	SV Talk, Tuning & Tweaking	8	22-02-09 10:15 PM
Pulls great but steady speed misfire & won't idle	randallp	SV Talk, Tuning & Tweaking	0	10-11-07 09:30 PM
r6 throttle	01 sv650s	Stuff Wanted	14	25-01-07 01:45 PM
r6 throttle	antony	SV Talk, Tuning & Tweaking	4	24-01-07 11:21 PM

06-06-06, 10:55 PM	#3
Saint Matt Guest Posts: n/a	Might sound stupid but could it be your chain? Mine just that cos the chain's just about dead...

06-06-06, 11:17 PM	#4
svrash Guest Posts: n/a	What gear are you in?.....................40 in 5th or 6th might cause a surge

07-06-06, 11:45 AM	#6
rwball Guest Posts: n/a	Cheers for the responses, it could be the chain then as it is the original and getting pretty old, but it doesn't feel like it's the chain. I'm not to sure which gear I'm in, and it seems a higher gear is better, but I'm certainly not in 5/6th. If I have the revs around 3/4k the problem doesn't seem so bad as when the revs are 5/6/7, again this is only noticeable at speeds below 40. I think I'm going to try and new battery first.

07-06-06, 12:51 PM	#7
ash Guest Posts: n/a	Mine is doing exactly the same thing as yours, although i know mine isn't the chain cause when idling the rev counter is bouncing around. Took it to the garage yesterday after checking all the vacuum pipes, fuel pipes etc They can't fit me in for another week but i did speak to the machanic there and he said try draining the carbs to see if there is water in them by unscrewing the drain plug and letting it drain into a jar or something. I looked in the Haynes and have located the drain plugs..... is it as simple as that ? I don't want to undo the drain plugs and petrol start pouring everywhere !!!

07-06-06, 01:03 PM	#9
ash Guest Posts: n/a	Hey TSM. You know what.... think you may have hit the nail on the old head there. Mine is sticking a little...and i stress a little, even when in the off position.... how did you sort it ? Or was yours still in the on position when ya realised ? Ive oiled mine the best i can without stripping it down.