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Discussion Starter · #1 ·


bike runs fine not even hot.

but i thought i would have a check on the plugs.

how do you check or adjust mixture i thought the computer did this.

cheers mark
 

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Fuel injection tends to run on the lean side. Your electrode tip loos to have carbon which indicates rich mix. I'm not sure you can manually adjust the mixture on this bike.
 

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If you think that you are running lean, you can adjust that to go a bit richer by inserting a small resistor in series with the coolant temperature sensor - probably a variable 100 ohm resistor will do the trick - and start from 0 ohms (the same setup for the computer, as you had before you added the resistor).
 

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bike runs fine not even hot.

but i thought i would have a check on the plugs.

how do you check or adjust mixture i thought the computer did this.

cheers mark


The CXT does not have a feedback system (closed loop) using O2 sensors so the ancient tech ECU only calculates fuel delivery based on input from the sensors. Modern gasoline has so many additives and oxygenates (alcohols and others) to reduce harmful emissions (by adding oxygen chemically to the combustion process)on modern vehicles with feedback EFI. The CXT has no way to compensate and your plugs look lean because of that. There are ways to fool the ECU by altering the sensor signals (the easiest being the coolant sensor as Don Seedsman has suggested)to enrich the A/F ratio. The CXT fuel injection system was the grand daddy development mule for the later PGM-FI systems used in the 1985 and later Honda automobiles. I was a senior master auto tech at a Honda car dealership back in those days. I remember it well. Other means of enrichment could be boosting the fuel pressure, or installing higher output fuel injectors.
 

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My Hayabusa is over 2 decades newer and it has no O2 sensor. It carries out fuel delivery pretty much the same way. Considering it doesn't have to deal with added calculations for a turbo, I'd say the CXT ECU is more advanced than what's on my modern Suzuki.
 

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Discussion Starter · #6 ·
something occoured to me reading the replies the fan runs all the time so does that point to the temp sensor being bad and would that affect the mixture .

cheers mark
 

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something occoured to me reading the replies the fan runs all the time so does that point to the temp sensor being bad and would that affect the mixture .

cheers mark


Has anyone checked the reading from the throttle position sensor? It can very easily be adusted to richen the mixture drilling the original bolts and replacing with allen head bolts for simple adjustment.... Adjust to the rich side of the spec in the book for more fuel...



PK
 

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something occoured to me reading the replies the fan runs all the time so does that point to the temp sensor being bad and would that affect the mixture .

cheers mark




Nope. The coolant temperature sensor (Tw) doesn't control the fan. There's a thermstatic switch for that in the radiator.



That's still not saying that you don't have a problem with that sensor or even the T1 sensor which is for intake air temperature.
 

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Discussion Starter · #9 ·
Begining to wish i had stuck with 2/strokes,


sooo much simpler.

cheers mark
 

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thanks dan i will keep you posted.

cheers mark
Mark you just need to trade that cranky 650T in for a reliable RG500. I was just down your way last week, I could have delivered one. Tropical Storm Dan chased me off before we could spend much time there.

Ed
 

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Discussion Starter · #13 ·
Mark you just need to trade that cranky 650T in for a reliable RG500. I was just down your way last week, I could have delivered one. Tropical Storm Dan chased me off before we could spend much time there.

Ed


hey ed do you fancy a swap then ,i would love a RG500 ,I see you have one by your signature.

lets have some pics anyway, you have me drooling.


mmmmmmmm Castrol R


give me a shout next time your down this way we can have a drink and a chat.

Cheers mark
 
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