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Sputters at about 1/4 throttle
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Thanks.
1981 KZ750E2
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- 650ed
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Attachment Advancer_2013-08-27.jpg not found
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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1981 KZ750E2
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It did make a difference with the sputter, but not completely. It still struggles at about 2500 rpm up.
I checked to see if my petcock is operating properly, and all seems well there. I guess the next step is to clean up all the electrical connections and make sure the coils are getting what they need. I have the green Dyna coils (they are relatively new), so I think I am OK there.
I am so close to getting this bike on the road! It shifts nicely and idles like a champ. I just need to get this sputter sorted.
Thanks again for all the help. I will most likely be picking your brains again soon. :blush:
1981 KZ750E2
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- Big Al
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Alan
1976 KZ900 LTD (sort of)
2005 FJR
2009 Hayabusa
www.kzrider.com/forum/11-projects/557845...-streetfighter-build
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Haybus wrote: If you still have points, the Dyna electronic ignition would be money well spent. Also, make sure you're getting 14.4V to the battery at 4000 rpm.
Alan
The 1981 KZ750-E2 doesn't use points; it already has electronic ignition. Ed
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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I cleaned and lubed the advancer, and it moves nicely. I checked the voltage at the coils, and there is less than a 0.5 V difference as compared to the battery. Is that close enough? I looked through the connectors, and all but one where nice and shiny. I cleaned that up and made sure the ground on the engine was sound.
After all that, it is still sputtering at about 3000 rpm and up. I took the rest of the day to service all three calipers, switched the forks from my parts bike to my project (the seals were leaking on my project bike), and then lubed and set the steering head bearings.
So, I have all the peripheral jobs complete. Now all I need is to get the engine running properly!
Is it time to maybe change the needle clip position? The idle is nice and smooth, so I am happy with the pilot circuit.
I wish I had a magic wand to get it going properly!
1981 KZ750E2
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- Motor Head
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- FIX UP YOUR BIKE RIGHT AND CHEAP
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Then if it is right, then make jetting changes. The easiest is the Needle which can be raised with either a clip position if so fitted, or shims. This would be for 1/4 throttle to 3/4 throttle approximately. There is of course some overlap between carb circuits. Yours would also have a slow main and a high speed main. The slow main may need increasing. Hard to say from not riding the bike.
1982 KZ1000LTD K2 Vance & Hines 4-1 ACCEL COILS Added Vetter fairing & Bags. FOX Racing rear Shocks, Braced Swing-arm, Fork Brace, Progressive Fork Springs RT Gold Emulators, APE Valve Springs, 1166 Big Bore kit, RS34's, GPZ cams.
1980 KZ550LTD C1 Stock SOLD Miss it
1979 MAZDA RX7 in the works, 13B...
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My problem is that I don't know that much about carbs, so even after riding it, I am unsure of the cause of the symptoms.
I will try to lift the needles to see if that maybe makes a difference.
Thanks for the help.
1981 KZ750E2
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- Motor Head
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1982 KZ1000LTD K2 Vance & Hines 4-1 ACCEL COILS Added Vetter fairing & Bags. FOX Racing rear Shocks, Braced Swing-arm, Fork Brace, Progressive Fork Springs RT Gold Emulators, APE Valve Springs, 1166 Big Bore kit, RS34's, GPZ cams.
1980 KZ550LTD C1 Stock SOLD Miss it
1979 MAZDA RX7 in the works, 13B...
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Alan
1976 KZ900 LTD (sort of)
2005 FJR
2009 Hayabusa
www.kzrider.com/forum/11-projects/557845...-streetfighter-build
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Motor Head wrote: I'm sure you've checked, but make sure the diaphragms don't leak on the slides. No pin holes,or leak at the lids. Slides also must be orientated correctly. Besides the hole where the needle drops into, there will be a vacuum hole in the slide. It must face the engine/ intake side of the carb.
I have checked the diaphragms for any tears, and they look good. Is there a specific way to check them, or is it just a visual inspection?
I was under the impression that the slides only went in one way, as the top of the diaphragm isn't round, but comes to a point on one side instead. I will certainly check to make sure I have them in the correct position.
Haybus: I do have a drain port on my carbs, so it isn't that bad at all. It is taking the carbs off the bike that sucks! Your cup idea seems to be a good one. Anything that saves time is worth it.
I wonder if it is worth changing the fuel level to the high end of the specifications. If I remember correctly, the spec is 3 mm +/- 1 mm. Maybe making them all 2 mm below the top of the float bowl would be a good thing (unless 1 mm wouldn't make a big difference).
Now, to be sure, it is the point at which the float bolt meets the carb body that I am to be measuring from, correct?
1981 KZ750E2
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