G
Guest
Guest
Hi everybody, long time lurker since before I bought my '82 GS750e from an older gentleman who could no longer ride. In fact, the community here is what convinced me to pull the trigger on the listing when it came up. As an amateur wrench on some newer bikes and cars I thought it would be a fun project, and thus far it has been!
When I got the bike it wouldn't start, and had a laundry list of minor issues. It is stock with the exception of a V&H 4 into 1 the previous owned put on. So I started following the incredible advice on offer here, and heeded the refrain to go through the existing knowledge.
1. Cleaned carbs, full dip and ultrasonic, replaced gaskets, checked float heights, bench sync, fuel screws 2 turns out
2. Replaced o-rings via cycleorings
3. New intake boots and airbox boots
4. Adjusted valve clearances, replaced valve case gasket
5. Replaced rusted out gas tank with clean OEM tank, replaced petcock with new OEM petcock (vacuum style with screwdriver turn, no lever)
6. Replaced boot between airbox & air cleaner. Ran silicon gasket maker around the seam of the airbox which is of the plastic variety with two molded halves with a seam running around the center on all sides. No identifiable holes, punctures, or issues.
7. New air filter
8. Changed oil and oil filter
9. Replaced spark plugs
The bike now starts easily, idles at 1100 until it gets warm, then surges to 3000-3500 rpm and hangs there. I've already got new OEM intake boots and airbox boots, and I've doublechecked they're installed properly and tried spraying both water and carb cleaner to test their seals with no response to either.
I checked throttle cable routing, and it's good with a little play, no binding. I've checked choke cable routing and it also seems to be good, although I did replace the OEM lever with an aftermarket, it doesn't appear to be holding it open or anything of that nature.
I've taken the bike out a couple times to see if there are any other symptoms, but she runs beautifully up through 5th, with great power and throttle response. There is some popping from the exhaust when I go off throttle and decelerate. Aside from that the only issue is the idle hanging around 3k. Edit: There is also significant, noticeable, blueing radiating out from the exhaust flange on #1 that does not match 2-4.
I've got a Carbtune, but as the old girl sits at 3k while warm that seems to be out of spec for syncing per the manual as well as the advice on Bikecliff's site, so I haven't yet tried it. That said, plugs 1 and 2 are too light and look lean, 3 is a little better, and 4 is a chocolate and looks right. From what I've read the aftermarket exhaust shouldn't be making it run lean enough to require rejetting, and the fact that there's disparity between plugs, and it doesn't hang until after warm doesn't seem like that would be the problem? It makes me think this might be a sync issue, but I don't know enough to say.
At this point I've scoured every old post I can find, and can't seem to make any headway on what to try next. Any advice would be accepted with extraordinary gratitude. Thanks!
When I got the bike it wouldn't start, and had a laundry list of minor issues. It is stock with the exception of a V&H 4 into 1 the previous owned put on. So I started following the incredible advice on offer here, and heeded the refrain to go through the existing knowledge.
1. Cleaned carbs, full dip and ultrasonic, replaced gaskets, checked float heights, bench sync, fuel screws 2 turns out
2. Replaced o-rings via cycleorings
3. New intake boots and airbox boots
4. Adjusted valve clearances, replaced valve case gasket
5. Replaced rusted out gas tank with clean OEM tank, replaced petcock with new OEM petcock (vacuum style with screwdriver turn, no lever)
6. Replaced boot between airbox & air cleaner. Ran silicon gasket maker around the seam of the airbox which is of the plastic variety with two molded halves with a seam running around the center on all sides. No identifiable holes, punctures, or issues.
7. New air filter
8. Changed oil and oil filter
9. Replaced spark plugs
The bike now starts easily, idles at 1100 until it gets warm, then surges to 3000-3500 rpm and hangs there. I've already got new OEM intake boots and airbox boots, and I've doublechecked they're installed properly and tried spraying both water and carb cleaner to test their seals with no response to either.
I checked throttle cable routing, and it's good with a little play, no binding. I've checked choke cable routing and it also seems to be good, although I did replace the OEM lever with an aftermarket, it doesn't appear to be holding it open or anything of that nature.
I've taken the bike out a couple times to see if there are any other symptoms, but she runs beautifully up through 5th, with great power and throttle response. There is some popping from the exhaust when I go off throttle and decelerate. Aside from that the only issue is the idle hanging around 3k. Edit: There is also significant, noticeable, blueing radiating out from the exhaust flange on #1 that does not match 2-4.
I've got a Carbtune, but as the old girl sits at 3k while warm that seems to be out of spec for syncing per the manual as well as the advice on Bikecliff's site, so I haven't yet tried it. That said, plugs 1 and 2 are too light and look lean, 3 is a little better, and 4 is a chocolate and looks right. From what I've read the aftermarket exhaust shouldn't be making it run lean enough to require rejetting, and the fact that there's disparity between plugs, and it doesn't hang until after warm doesn't seem like that would be the problem? It makes me think this might be a sync issue, but I don't know enough to say.
At this point I've scoured every old post I can find, and can't seem to make any headway on what to try next. Any advice would be accepted with extraordinary gratitude. Thanks!
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