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Tuning with an o2 sensor, advice/tips?
- hardr0ck68
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- Who put the what in the where?
1977 kz650 c1
bought it because I was told it would never run again...I like to prove people wrong.
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- Motor Head
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- FIX UP YOUR BIKE RIGHT AND CHEAP
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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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- MFolks
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Bikes have a lot more vibration of frequency and magnitude than cars.
1982 GPZ1100 B2
General Dynamics/Convair 1983-1993
GLCM BGM-109 Tomahawk, AGM-129A Advanced Cruise Missile (ACM)
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- loudhvx
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I like to break up the throttle into 2 general regions; cruising and accelerating. Cruising is generally 1/16 to about 1/4 throttle. Accelerating is about 1/4 and above. But really, 3/16 to about 3/8 is more like a transitional throttle position.
To check the cruising range, I just hold the throttle steady at 1/16, 1/8, 3/16, and 1/4 while in top gear and wait til the speed tops out. (You get going pretty fast at 1/4.) For cruising you want to be in the high 13 to mid 14 range. With pods, you want to be a little richer like mid 13 to 14 or so at the leanest. This is because the pods are affected by turbulence. Wind gusts and seating position can affect the AFR, so you want to err a little on the rich side. I get best results if it just tops out near 14 on a hot day (85 to 90 deg F). From about 3/16 to 3/8, though, the AFR should transition down into the power range (somewhere around 11.5 or 12).
Then I check 1/2, 3/4, and WOT while accelerating through the gears. For this range, the AFR should drop down into the 11's and will sweep upwards as the RPMs increase. (I really like the analog AFR gauges that Innovate has. That way you don't need to focus on individual numbers and you can see how fast the needle is swinging. If you are using a digital readout, it's harder to get a feel for how fast the AFR is changing). Only pay attention to the AFR after you're past 5000 RPM or so. You really won't go WOT from idle in a fast launch. (Normally you'll have the revs up and will be using the clutch.) Ideally you want the needle to sweep from about 11.5 up to 13 just as you reach redline, or your normal shift point. (I usually do that by sound based on how I normally accelerate when I'm going all out.) Best power is in the 12 to 12.5 range, so you want the AFR to sweep through that range as you accelerate. Because there is such a wide sweep, you have to widen the margin to about 11 to 13.
With manual slide carbs, if you whack the throttle too fast, the AFR will plummet down into the 10's. That's too rich and you'll notice some bogging. You need to roll the throttle to keep above 11.0, ideally (in my opinion).
If you are hitting the 14's at WOT, in my opinion, you are too lean and should go up at least 4 jet numbers on the main.
Another thing I should add about mechanical slide carbs, is that some have and adjustable stop for the WOT position. Make sure the slide does not go above the roof of the throttle bore. If it does, that means the last bit of throttle only adds fuel, but no air. This makes the AFR suddenly go rich when the throttle hits the throttle stop. If it's really bad, you will feel the bike actually accelerate if you are at WOT and you start to close the throttle. This also results in an error in main jet selection since it will seem too rich at WOT, but you'll actually be lean for most of the last half of the throttle movement. Just double check the WOT position of the slide, especially if you change needle positions or shims.
1981 KZ550 D1 gpz.
Kz550 valve train warning.
Other links.
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- bountyhunter
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1979 KZ-750 Twin
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- bountyhunter
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Amen.Be very careful! the glass bodied fuel filters have caused more than a few car fires. I'd suggest at your earliest chance to replace it with a plastic body fuel filter.
Bikes have a lot more vibration of frequency and magnitude than cars.
1979 KZ-750 Twin
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- hardr0ck68
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1977 kz650 c1
bought it because I was told it would never run again...I like to prove people wrong.
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- hardr0ck68
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- Who put the what in the where?
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1977 kz650 c1
bought it because I was told it would never run again...I like to prove people wrong.
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- hardr0ck68
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The angle is less than perfect, the bung should be slightly higher up the pipe (10 o'clock not its current 8 o'clock position) but such is life.
1977 kz650 c1
bought it because I was told it would never run again...I like to prove people wrong.
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- hardr0ck68
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- Who put the what in the where?
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1977 kz650 c1
bought it because I was told it would never run again...I like to prove people wrong.
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- hardr0ck68
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I honestly don't know if it matters much either way so long as the plugs stay clean at idle.
He told me to shoot for about 12.5 at load as well. I guess I had better order some new jets!
1977 kz650 c1
bought it because I was told it would never run again...I like to prove people wrong.
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- Motor Head
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- FIX UP YOUR BIKE RIGHT AND CHEAP
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Did you do a before Coil mod voltage reading with it running, and a after? If so Difference Please. Thanks.
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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