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83key hin carbs
- cricketfire46
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83 kz750 ltd, dyna coils, k&n, mac 4->1 just rolled 50k
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- JR
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As long as you are not looking for tiny pilot jets you can get the necessary Keihin jets from Z1 Enterprises.
www.z1enterprises.com/SearchResult.aspx?...True&KeyWords=Keihin
They are only a dollar or 2 each so its cheap to try different sizes.
The stock jetting should be Secondary main = 125 and Primary main = 60 or maybe it's 62. With my eyesight I need a magnifying glass to see the numbers stamped on the jet :laugh:
If you have the stock airbox and are only rejetting for the 4->1 then try replacing the 125 with a 130 or 135. If that does'nt do the trick then go up another size. next try bumping up that 62 a bit.
Z1 dont list the smaller sizes but they do have them if you need them.
I'm thinking the 130 or 135 would probably do it.
All this is assuming they are Keihin CV34 carbs. I thought the 83 750 had BS 34s.
Good luck.
1980 kz750E1, Delkevic exhaust
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83 kz750 ltd, dyna coils, k&n, mac 4->1 just rolled 50k
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The only way to tell if it is running rich is to pull the spark plugs and look at the colour.
Black = rich
Tan = just right
White = lean
I think the NGK website will have some more exact detail and pics. Also. Do a search here on "plug chop".
1980 kz750E1, Delkevic exhaust
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83 kz750 ltd, dyna coils, k&n, mac 4->1 just rolled 50k
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Time to send carbs to wiredgeorge perhaps.
www.wgcarbs.com/
1980 kz750E1, Delkevic exhaust
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wiredgeorge Motorcycle Carburetors
Mico TX
www.wgcarbs.com
Too many bikes to list!
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83 kz750 ltd, dyna coils, k&n, mac 4->1 just rolled 50k
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i do have the aftermarket dyna coils on my bike and they are set up in the proper order to fire do i am not inclined to think that the ignition system itself is the actual problem. if you guys have any other ideas that would be great. ive been told by several long time riders that it is a jetting issue
if you guys have any other ideas that would be great.
Other ideas - - -
Good coils are of course important, but are only one ignition component, along with voltage being supplied, condition of plug wires, plug caps, and plugs. Where visual observation reveals a good fat spark at the plug tips, this is evidence that power and delivery of the ignition system are okay. Of course, timing of the good spark is also critical. If not already done, would remove plugs and actually look at the spark.
While there may indeed be a jetting issue, the reported symptoms are also consistent with other possibilities, such as too tight valve clearances. And the best way to eliminate that possibility, if not already done, is by performing a compression test on each cylinder and measuring all the valve clearances to assure the gaps are within specs.
Moreover, the reported symptoms are also consistent with possibility of a too high service fuel level inside the float bowls. If not already done, would check service floatbowl fuel levels, using the clear tube method.
And there's more, because the reported symptoms are also consistent with possibility of a leaking float needle/seat interface combined with an obstruction somewhere in the floatbowl overflow circuit (inside the floatbowl, or maybe a kinked or plugged drainage hose outside the carb). If not already done, would "sniff-test" the crankcase oil to help determine whether there's any fuel contamination.
Good precisely timed spark; adequate compression and proper valve clearances; correct fuel levels; non-leaking float needle sealing and properly functioning overflow circuits. All okay? Great!
After the above possible problem areas have been checked and eliminated, it would imo then be appropriate to address internal condition of the carbs (cleanliness of both fuel and air passages) and finally the jetting.
The peanut gallery has spoken.
Good Luck!
1973 Z1
KZ900 LTD
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wiredgeorge Motorcycle Carburetors
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83 kz750 ltd, dyna coils, k&n, mac 4->1 just rolled 50k
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