Misfire advice - SV650.org

05-06-10, 02:45 PM

edit: 99 curvy, completely standard, slide restricted. 23k

Only happens when first engaging the throttle, it used to happen once every few rides, now its a few times every ride. Nothing to do with weather.

Im thinking.

Choke plungers (pretty sure they are fine though)
Replace plugs
Then leads
Then coils.

05-06-10, 02:50 PM

i was thinking fueling to be honest, is it a curvy, have you balanced carbs, straight thru zuast on it, rejetted

Richie · 05-06-10, 02:55 PM

Quote:

Originally Posted by davepreston

i was thinking fueling to be honest, is it a curvy, have you balanced carbs, straight thru zuast on it, rejetted

+1

05-06-10, 02:58 PM

'99 Its restricted with slides, standard exhaust and air filter.

Not balanced it myself yet, its runs very smoothly though.

I agree regarding possible fueling due to it only happens with first opening the thottle.

TSM · 05-06-10, 06:48 PM

everytime the carbs are touched they should be rebalanced, especialy if restricters were put in, also check the TPS

11-12-10, 10:27 PM

Well reblancing didnt help, it misfired during balancing, without the airbox on it was ridiculousy loud!

I was looking directly at the carb intake too, so i know its the rear cyclinder. I **** myself!

New plugs in the post.

Biker Biggles · 11-12-10, 10:42 PM

Misfire/hesitation on opening the throttle could be an intake air leak which is quite common.Check the seating of the airbox on the carbs,and any loose tubing like crankcase breathers.Double check the choke plungers as they are often sticky.Water in fuel is another one to look at.

rictus01 · 11-12-10, 10:44 PM

good carb clean,nice fresh fuel and no crap in the tank, check for air leaks on both the inlet and outlet sides, whip the rocker cover off and check the valves are seated properly and gapped correctly while you're there,once that's all done move on to things like; change the plugs, check the plug caps, check the spark is reliable to rule out wiring/coils/pickup etc.

Cheers Mark.

11-12-10, 10:53 PM

Quote:

Originally Posted by rictus01

good carb clean,nice fresh fuel and no crap in the tank, check for air leaks on both the inlet and outlet sides, whip the rocker cover off and check the valves are seated properly and gapped correctly while you're there,once that's all done move on to things like; change the plugs, check the plug caps, check the spark is reliable to rule out wiring/coils/pickup etc.

Cheers Mark.

No hesitation, just very occasional single misfire.

All done previously, gonna inspect coil and leads tomorrow, it happens once a ride, but always just after opening throttle from idle.

The TPS nothing in the manual about testing this?

rictus01 · 11-12-10, 10:58 PM

given all the variables are correct, the easiest thing to do is get an Orger close by with a curvy and component change one afternoon to find the offending bit.

Cheers Mark.

05-06-10, 02:45 PM	#1
beabert Guest Posts: n/a	Misfire advice edit: 99 curvy, completely standard, slide restricted. 23k Only happens when first engaging the throttle, it used to happen once every few rides, now its a few times every ride. Nothing to do with weather. Im thinking. Choke plungers (pretty sure they are fine though) Replace plugs Then leads Then coils. Last edited by beabert; 05-06-10 at 03:01 PM.

05-06-10, 02:50 PM	#2
davepreston Guest Posts: n/a	Re: Misfire advice i was thinking fueling to be honest, is it a curvy, have you balanced carbs, straight thru zuast on it, rejetted

05-06-10, 02:58 PM	#4
beabert Guest Posts: n/a	Re: Misfire advice '99 Its restricted with slides, standard exhaust and air filter. Not balanced it myself yet, its runs very smoothly though. I agree regarding possible fueling due to it only happens with first opening the thottle. Last edited by beabert; 05-06-10 at 03:02 PM.

05-06-10, 06:48 PM	#5
TSM The Sick Man Mega Poster Join Date: Nov 2004 Location: Peckham.SE.LDN Posts: 4,768	Re: Misfire advice everytime the carbs are touched they should be rebalanced, especialy if restricters were put in, also check the TPS __________________ 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

11-12-10, 10:27 PM	#6
beabert Guest Posts: n/a	Re: Misfire advice Well reblancing didnt help, it misfired during balancing, without the airbox on it was ridiculousy loud! I was looking directly at the carb intake too, so i know its the rear cyclinder. I **** myself! New plugs in the post.

11-12-10, 10:42 PM	#7
Biker Biggles Member Mega Poster Join Date: Jan 2005 Location: Barnet Herts Posts: 5,071	Re: Misfire advice Misfire/hesitation on opening the throttle could be an intake air leak which is quite common.Check the seating of the airbox on the carbs,and any loose tubing like crankcase breathers.Double check the choke plungers as they are often sticky.Water in fuel is another one to look at. __________________ On a clear day we stand there and look further than the ordinary eye can see.

11-12-10, 10:44 PM	#8
rictus01 Member Mega Poster Join Date: Jul 2003 Location: South London Posts: 9,799	Re: Misfire advice good carb clean,nice fresh fuel and no crap in the tank, check for air leaks on both the inlet and outlet sides, whip the rocker cover off and check the valves are seated properly and gapped correctly while you're there,once that's all done move on to things like; change the plugs, check the plug caps, check the spark is reliable to rule out wiring/coils/pickup etc. Cheers Mark. __________________ Life should not be a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, in a cloud of smoke, thoroughly used up, totally worn out, and loudly proclaiming, 'Wow! What a Ride!

11-12-10, 10:58 PM	#10
rictus01 Member Mega Poster Join Date: Jul 2003 Location: South London Posts: 9,799	Re: Misfire advice given all the variables are correct, the easiest thing to do is get an Orger close by with a curvy and component change one afternoon to find the offending bit. Cheers Mark. __________________ Life should not be a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, in a cloud of smoke, thoroughly used up, totally worn out, and loudly proclaiming, 'Wow! What a Ride!

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