Hi guys,
Was hoping you could help me figure out why my GS starts on only one cylinder. The one on the left side (as you sit on the bike) fires up but it takes the right one a few seconds (sometimes as much as 30) to get going. My knowledge of engines is limited so not sure what is going on. Once the engine is at temp it will start with no problems, just when it is first started after cooling down. Also if you twist the gas too much while it is on one cyl, it kills the engine, although a gentle twist helps it pick up and start quicker.
Confused!
I would suspect either carbs or spark. more likely carbs arent totally clean.
I'm going for the carbs on this one too.
make sure the choke is actually going all the way on both carbs, then give em a good cleaning. If the choke is stuck for one carb, that cylinder wouldn't fire until the engine block got hot enough to not need the rich air/gas ratio from the choke. Just a theory.
Quote from: smartroad on October 05, 2008, 10:28:47 AM
Hi guys,
Was hoping you could help me figure out why my GS starts on only one cylinder. The one on the left side (as you sit on the bike) fires up but it takes the right one a few seconds (sometimes as much as 30) to get going. My knowledge of engines is limited so not sure what is going on. Once the engine is at temp it will start with no problems, just when it is first started after cooling down. Also if you twist the gas too much while it is on one cyl, it kills the engine, although a gentle twist helps it pick up and start quicker.
Confused!
clogged idler jet on the non-functioning cylinder, and/or a bad spark plug wire.
i'd bet on the plug wire or coil pack. if your battery is low at all, it will hurt starting considerably.
start with:
full water (distilled only) in the battery, fully charged
change your plug wires/coils from side to side to see if the problem follows (big hint from that one!)
check your float heights
pull your idler jet and take a peek
Thanks for the advice all :)
It is strange, I have replaced the valve cover gasket as it was leaking. Not only has the leak stopped, but the bike seems to be firing up OK. It may well be down to the fact this morning it was warmer then it has been for a while 15C rather then closer to 5C, so I will see tomorrow when it is meant to be much cooler. But that wouldn't explain why it happened in 20C+ back in the summer. :dunno_white:
This is before I have tried anything else as well. I do find it unlikely that a valve gasket would cause the problem, but as said before, my knowledge of engines is limited so I could very well be wrong!!
Quote from: ohgood on October 05, 2008, 02:53:58 PM
full water (distilled only) in the battery, fully charged
change your plug wires/coils from side to side to see if the problem follows (big hint from that one!)
check your float heights
pull your idler jet and take a peek
Can the leads be pulled? They look as if they part fo the coil. Or would it just be better to just swap the coil/leads together anyway?
Mine did exactly that consistently until I pulled the carbs, which were clean(but I'd run Sea Foam through for weeks). I rejetted, replaced a missing mixture screw :o , pulled the airbox and dropped in a lunchbox filter, and did a valve adjust. Then the moment of truth, hit the starter button, it ROARED into life, ran up to about 4K instantly, we settled the idle screw and it was astonishing. My buddy who did the work with me and I stood there with ear to ear grins. Runs like a champ now and starts first try and doesn't stall. Sounds a lot nicer too.
Quote from: Teek on October 13, 2008, 11:51:26 PM
Mine did exactly that consistently until I pulled the carbs, which were clean(but I'd run Sea Foam through for weeks). I rejetted, replaced a missing mixture screw :o , pulled the airbox and dropped in a lunchbox filter, and did a valve adjust. Then the moment of truth, hit the starter button, it ROARED into life, ran up to about 4K instantly, we settled the idle screw and it was astonishing. My buddy who did the work with me and I stood there with ear to ear grins. Runs like a champ now and starts first try and doesn't stall. Sounds a lot nicer too.
My carbs were recently (about 6 months) cleaned when it wouldn't start at all :lol: At the weekend I will try changing over the coils, as they are easier to manourver. Then move onto the engine itself.
I had a loose plug wire in one of the coils that caused my starting on one cylinder on my 02 GS. They are screwed into the coil and bonded in place and won't rotate in the coil if all is in order. Quick check is to just pull off the plug wire from the plug and see if you can rotate it. If you can rotate it you can tighten it up for a quick fix and if it won't go tight (clockwise) then cut a bit off the end and screw it in tight. Mine started on one cylinder and quickly picked up the other cyl like you describe but I got caught one rainy day and it cut out and I had to ride home on one cyl. I replaced the wire and put a big lump of diaelectric grease on the end before screwing it in. No problem since.