It's very hard to start. Definitely easier when the bike has been out in the sun for a few hours, but still not easy. On several occasions, I've drained the battery completely while fiddling with the choke (only a few seconds of cranking at a time, of course). I'll typically get a few cycles of combustion, might even run for 3-5 seconds. After that, it may not appear to fire at all no matter where I position the choke control. Cranking speed sounds good. I haven't pulled the plugs, but it certainly smells like it's getting fuel. Sometimes it backfires after it runs for a few seconds. I'd check the timing, but since it's electronic and not adjustable that's out. The few times I've gotten it to run, it will run very well once it's completely warmed up. At this point, I'm going to adjust the valve lash and throw in a new set of plugs. If I can get it to run for long enough to warm it up, I'll also try to borrow a tool and sync the carbs. If those don't fix it, is there anything else I should try before taking the carbs off and ripping them apart?
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fastpakr
Hard start troubleshooting
To preface this, I have an 82 750E with about 25k on it that I just bought a few weeks ago. I've only ridden it for a few minutes and don't know the history of it. It has pod filters, and I don't know if it was re-jetted after they were installed.
It's very hard to start. Definitely easier when the bike has been out in the sun for a few hours, but still not easy. On several occasions, I've drained the battery completely while fiddling with the choke (only a few seconds of cranking at a time, of course). I'll typically get a few cycles of combustion, might even run for 3-5 seconds. After that, it may not appear to fire at all no matter where I position the choke control. Cranking speed sounds good. I haven't pulled the plugs, but it certainly smells like it's getting fuel. Sometimes it backfires after it runs for a few seconds. I'd check the timing, but since it's electronic and not adjustable that's out. The few times I've gotten it to run, it will run very well once it's completely warmed up. At this point, I'm going to adjust the valve lash and throw in a new set of plugs. If I can get it to run for long enough to warm it up, I'll also try to borrow a tool and sync the carbs. If those don't fix it, is there anything else I should try before taking the carbs off and ripping them apart?Tags: None
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Anonymous
Could be a weak spark. You might try some new spark plugs and spark plug caps.
GS's can be very cold blooded, and since yours doesn't have the original airbox, make sure you have the correct jetting for the pods.
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Anonymous
NEEDS MORE FUEL!
Check your petcock output.
Check your fuel filter.
Check your idle mixture.
Spray some starting fluid into air cleaner box, does it start? Needs more fuel.
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SqDancerLynn1
CHeck the choke cable adjustment. Make sure to do the routine. turn the petcock to Prime to fill carbs, turn bact to. Give it FULL choke and NO throtle
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fastpakr
I'll check the choke adjustment tomorrow night. As far as testing petcock output - is there a specific quantitative measurement test that I can run?
This may be a dumb question, but with the pod filters, should I just spray the starting fluid right onto them? Or is there a better way to get it into the carbs?
I don't have the Clymer manual nearby - where is the stock filter? Is it an easy part to pick up or would I be better splicing in a generic parts store filter and eliminating the stock unit?
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Anonymous
There should be a opaque "see thru" fuel filter in-line with your fuel hose leading from your petcock to your carbs. If there isn't one, you should install one now.
Spray the starter fluid into your pods (all 4) and try to start. Keep sprayng as you crank (don't saturate). If your motor starts and then dies, you know it's a fuel flow problem. Let's go from there.
P.S. Get a service manual ASAP.
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fastpakr
Originally posted by basarajThere should be a opaque "see thru" fuel filter in-line with your fuel hose leading from your petcock to your carbs. If there isn't one, you should install one now.
Spray the starter fluid into your pods (all 4) and try to start. Keep sprayng as you crank (don't saturate). If your motor starts and then dies, you know it's a fuel flow problem. Let's go from there.
P.S. Get a service manual ASAP.
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Anonymous
HARD START???? GS700ES
I just dropped my bike off for the same problem.
Last year I cleaned them myself( Carbs) , and didn't realize that I needed to Kream the tank. so I did it and i was still geting hard starts( drain the battery) then when it did run it would bog out bad in first, then it would hit 5000 rpm and rip right along.
Wonder if my problem this whole time is the petcock, that seems to be all screwed up ( just cost me $300 for the carb clean and syn, when they are done next week)
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fastpakr
OK, there was no fuel filter in place. Spark plugs should arrive in the next day or so, I'll put those in, install a filter, and adjust the valves before hitting the starter button again. I drained the fuel in the tank into my truck, with the petcock on prime the fuel flow was very rapid so I think the petcock is fine.
While waiting on my fork parts to arrive, I pulled the carbs off to clean them up and put in a new set of o-rings. I was somewhat surprised by the jetting - main jets were #130, bigger than I expected even with the pod filters and aftermarket exhaust that was on it (stock was #112.5 I believe). Is that a reasonable size? I'll write down the rest of the numbers tonight and post them, that's the only one I committed to memory. If somebody has rejetted a carb on a TSCC 750 for intake/exhaust changes I'd love to know where you ended up for settings.
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Anonymous
Jets and Troubleshooting
My bike is an 80 750e with 83 carbs. It is cold blooded too. I just bought pod filters and a stage one kit. The mains are 120. I think you problem is like mine, not enough fuel. A tiny bit of starter fluid and it fires right up. From there it is either the choke circuit being clogged or air, too much air.
As far as a quatitative approach to how much fuel you have moving to the carbs just prime them before you try to start. Don't remember if my old 82 had a primer setting on the petcock. If it doesn't you can try priming it by (kinda gross) opening the diaphragm manually (I'll leave it to your imagination as to how to do this) using the smaller hose that is connected to your engine, not the bigger one connected to the carbs.
If you have gas in the carbs but the engine won't start with full choke and no throttle, something is blocking the gas in the carbs. This is why starter fluid helps diagnose the issue.
K-
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Dink
Clean out the choke circuits in your carbs, if the choke isnt working it is not surprising the bike is difficult to start. After all your carbs can never be too clean, and of cause it also remeoves this area as a possible cause.
Dink
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fastpakr
I've already dipped the first carb and will probably do the rest tonight or tomorrow. Hopefully it will make a difference.
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sv650
Electrical soluition?!?
Check your main ground. I had similar problem, and ran a booster cable from the negative battery post to the engine case -- started & ran just fine. So I removed the main ground wire & cleaned the terminals -- made a big difference.
SV
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