Clinician
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Post by crst on Jul 29, 2010 19:10:22 GMT -6
Problem found. Hey Hey!!
After testing all of the electronics Thanks to all the great test procedures I found posted on this site, I started with the mechanical side today.
Started with the valves, the exhaust valve was tight. I adjusted it to .004, intake valve was fine.
The I moved to the carburetor. I removed it and started breaking it down, The first piece I removed was the top cover for the diagram and BINGO! there it was a 1/4" split in the rubber.
I put a dab of rtv silicone on it, let it dry and put it back on and wala RPMs, power & speed are back. Now I am going to order a new one for it.
Great learning curve for me. It all turned out to be a coincidence
after changing the CDI and road testing that the diagram split.
Well I did not know anything about these scooter before this and now I know it pretty well thanks to all of you and this Forum
Thank You All.
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Clinician
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Post by crst on Jul 25, 2010 20:11:46 GMT -6
I checked the spark today, has a blue spark. Very tiny.
It has a NGK plug # C7HSH with a gap of .20
Is this the correct gap?
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Clinician
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Post by crst on Jul 25, 2010 8:16:02 GMT -6
Today I am going to check out the quality of spark with the old
stock CDI.
I agree the purple performance CDI that I put on it started the problem only minutes later & after only a few miles had knocked it down from 60-65mph to 38mph max. almost as though I had put a rev limiter on it instead of a CDI.
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Clinician
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Post by crst on Jul 24, 2010 18:27:21 GMT -6
Sorry about that. I will check the connections again.
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Clinician
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Post by crst on Jul 24, 2010 18:13:09 GMT -6
Thank you Alleyoop
I will look into the lighter weights for the Variator, and remove the spark plug and check for a hot blue spark.
Perhap I should just move the power wire for the choke to a wire that is hot when the ignition is on.
Yesterday I ordered a new coil & spark plug.
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Clinician
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Post by crst on Jul 24, 2010 16:44:51 GMT -6
This is a Roketa MC19-150 scooter with a 157QMJ 150cc engine.
I replaced the CDI unit to obtain more power for climbing hills and for riding with a passenger.
The first test ride after changing the unit I could only go 38mph.
I put the old CDI back in it (that was getting me 60-65mph) now
it is only giving me 38mph max speed as well.
Both CDI units are A/C (the two pin plug has two wires).
Twice after changing back to the old CDI while driving a full throttle suddenly it started giving me more power back up to 55 and then dropped back down after only a few minutes. It has not
cleared up again since then.
Only 700 miles on this scooter.
Removed and checked the fuel screen from the fuel tank and diagram pump. Screen is clean and tested the diagram pump with vacuum,works fine, filter is clean hoses are all perfect condition and clamped tight.
Intake filter is clean all hoses are good and clamped tight. Checked all wiring connections for all components.
Battery is full charged and generator is working good.
Removed and tested the fuel inricher from the carb, tested good.
But I did find only 2 volts feeding the inricher, should be 12V if I am not mistaken. So I disconnected it and feed it 12 volts then took it for another test ride, no help still only 38mph.
Starts perfectly hot or cold. Runs smooth all the way from idle to full throttle. It's like from half throttle to max there is no change in rpms or the way it sounds.
Thank you in advance for any help with this.
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