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bogging after rebuild
- rdgrnr
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The synopsis is as follows:
No problems prior to rebuild, but since I was bringing the 77 back to life, I felt a good cleaning with a rebuild was in order. I installed the kits from K&L with 15 pilots, 102.5 mains, and needles set at 2nd from bottom. The needle and seats were replaced as well. To be honest, I forgot to write down what I did the float height at (inverted dry method). I also bench-syched them using the drill bit method. The air screws were initially set at 1 1/2 and I adjusted them running for the best idle at about 1000 rpm, which were all less than 1/8th turn. Slow acceleration seems to be good with smooth running at 5000. I'm using B7ES plugs, and have done the wg mod. There are no other mods that have been done. Fuel flow seems to be good as the petcock was cleaned as well. The air boots are new with a new K&N filter in the box.
Should I have used the bigger pilots that were supplied in the kits, or is this a float height issue as I have yet to do the wet method?
Feels like too much air before the fuel catches up to the demand. The intakes were replaced with good used ones prior to the rebuild, and throttle response was good at that time. I have not done the valve adjustment.
Any advice?
Thanks
77 KZ650B1
80 440 LTD Sold
78 GL1000 Naked Wing Sold
80 CM400E Sold
Brainerd, MN
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- wiredgeorge
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The "bench sync" you did was counter productive. The purpose of a bench sync is to get the slides roughly at the same level which your technique did but more important, to set the slide heights in the middle of the adjustment range of the idle adjust screw which you CAN NOT do using the too-large drill bits. I have explained how to bench sync many times in the past so won't attempt to do this once again here unless you can't find the correct technique from past posts.
wiredgeorge Motorcycle Carburetors
Mico TX
www.wgcarbs.com
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- rdgrnr
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Thanks
77 KZ650B1
80 440 LTD Sold
78 GL1000 Naked Wing Sold
80 CM400E Sold
Brainerd, MN
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- vach
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1979 kz650 B. Chicago, Illinois
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- wiredgeorge
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wiredgeorge Motorcycle Carburetors
Mico TX
www.wgcarbs.com
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- bountyhunter
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From what I read, that is the classic symptom of low fuel level in the bowls. In fact, on the tune up procedure I read, the way to verify fuel level is optimum is to hold it in second gear at about 2K RPM and roll the throttle on hard. It should pull hard without stumbling. If not, raise the level 1/2 mm. repeat until right.I am having some bogging at quick-throttle after I rebuilt my 24's. It dies unless I release the throttle.
YMMV
1979 KZ-750 Twin
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- rdgrnr
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The jetting is fine. You need to ensure that the adjustments I suggested are done as I suggested and that you have the pilot circuits cleaned/clear and pilot air/fuel mixture adjusted properly.
Ok,wg, will do and thanks.
77 KZ650B1
80 440 LTD Sold
78 GL1000 Naked Wing Sold
80 CM400E Sold
Brainerd, MN
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- rdgrnr
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[/quote] From what I read, that is the classic symptom of low fuel level in the bowls. In fact, on the tune up procedure I read, the way to verify fuel level is optimum is to hold it in second gear at about 2K RPM and roll the throttle on hard. It should pull hard without stumbling. If not, raise the level 1/2 mm. repeat until right.
I am suspecting a combination of improper sych, and fuel levels being off...will be rigging up a wet check tube hopefully if I have time this weekend.
Kevin,
The needle was set there when I took them apart, and I think I read the re-assembley info to put it there as stock. I'll have to look again to be sure.
77 KZ650B1
80 440 LTD Sold
78 GL1000 Naked Wing Sold
80 CM400E Sold
Brainerd, MN
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