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 Zuma starts but dies after 1 minute on idle 
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Post Zuma starts but dies after 1 minute on idle
As the title suggests that is my problem.

Theories:
1. Too lean or too rich? (I am new to mechanics and I would need advice on how to fix this)
2. The vacuum line is compromised? Maybe a crack or a leak? How would I test this?

Again, I am new to mechanics, this is my first vehicle. I bought the scooter used but in a factory state.
I installed:
70cc Polini engine
Yasuni R exhaust
OEMST Carb (same size as stock but it's supposed to be better)
Throttle mod
Dual headlight mod
Polini CVT
Polini variators 6.9 g

(electric starter doesn't work for some dumbass reason, so I got a new one but haven't installed it yet because I need to get the rear tire off, but to do that I need a freaking 24 mm socket which I do not have so I had to order that too)

I would really like so suggestions on pros about why my scooter is bogging down on idling after a minute and how to adjust the air-fuel mixture and what main jet I should use. Thank you so much.


Sun Dec 17, 2017 9:19 pm
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scooters and mods: 08 zuma dual headlight tmod rally kit cutom red paint koso mirros red anodized trans bolts
Post Re: Zuma starts but dies after 1 minute on idle
What the duck is an oemst carb and who sold it to you
What brand is it
What jets are in the carb size and brand
What plug are you running

Is the carb bowl dry after it dies
Those rollers are too heavy for that pipe and that it won’t even come close to recognized high enough to get into the power band of the pipe well that is depending upon what polini kit you have

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2008 zuma dual headlight mod koso mirrors liquid cooled polini corsa kit leo vince zx stage 6 variator rally kit custom red paintFUEL INJECTEDsoon to be 100cc
2008 stella olive custom ported 177 cc kit dechromed ford tear drop tail light alive and breathing and awaiting cosmtic surgery thanks to an trump cager
1985 elite 150 how long can i leave it stock


Mon Dec 18, 2017 5:35 pm
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Post Re: Zuma starts but dies after 1 minute on idle
Carb: https://www.ebay.com/itm/Yamaha-Zuma-YW ... Swqu9VNmw3

I am planning on getting dr.pulleys 6.5g pulleys

I have a BR9ES spark plug

It's an 80 main jet

Carb bowl is not dry


Mon Dec 18, 2017 11:09 pm
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scooters and mods: 08 zuma dual headlight tmod rally kit cutom red paint koso mirros red anodized trans bolts
Post Re: Zuma starts but dies after 1 minute on idle
Well considering it’s some cheap China knock off carb god only knows wheee your jetting is going to be and what jets are the right ones for the carb that is not an oem tk carb
You failed to mention pilot jet where the needle is set where is your af screw set why did you remove the oem carb
You do have the air box installed properly
Get several plugs and read how to do a proper plug chop and start there but I’m guessing
Even 6.5 is going to be way heavy you will need to be in the 4.5 to 5.0 gram range with that pipe
But again what polini kit are you running

_________________
2008 zuma dual headlight mod koso mirrors liquid cooled polini corsa kit leo vince zx stage 6 variator rally kit custom red paintFUEL INJECTEDsoon to be 100cc
2008 stella olive custom ported 177 cc kit dechromed ford tear drop tail light alive and breathing and awaiting cosmtic surgery thanks to an trump cager
1985 elite 150 how long can i leave it stock


Tue Dec 19, 2017 5:41 pm
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Post Re: Zuma starts but dies after 1 minute on idle
I have a cast iron Polini 70cc kit

I could go back to the OEM carb if that is necessary, but I changed the carb because my scooter wouldn't kickstart at all before, especially in cold weather.

Thanks for the variator tips, very helpful

I replaced my starter since old one was so rusty it wouldn't move. Good news is that the new one rotates, but once I install it it doesn't turn over the moped. The relay just clicks. Any suggestions? I was thinking bad starter clutch.

And I do have the airbox installed properly though I should say it is aftermarket, should I go back to OEM?


Tue Dec 19, 2017 10:00 pm
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Post Re: Zuma starts but dies after 1 minute on idle
Also I don't know what you meant by where the Jets are set, I just know that they couldn't go in any further when I got them.


Tue Dec 19, 2017 10:02 pm
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Post Re: Zuma starts but dies after 1 minute on idle
Cast iron doesn’t help polini offers 2 very different cast iron kits
One that needs a much larger carb to run one that will work with the stock carb but The power band is set very close to a stock 50 cc bore

Your battery is weak or dead plus you have a big bore kit so unless you installed a battery with a few more cranking amps the oem will struggle to turn the engine over

Look up the threads about tuning carbs and learn about carbs you about have a shitnton to learn and do before you even think about riding that scoot unless you want to blow it up

_________________
2008 zuma dual headlight mod koso mirrors liquid cooled polini corsa kit leo vince zx stage 6 variator rally kit custom red paintFUEL INJECTEDsoon to be 100cc
2008 stella olive custom ported 177 cc kit dechromed ford tear drop tail light alive and breathing and awaiting cosmtic surgery thanks to an trump cager
1985 elite 150 how long can i leave it stock


Wed Dec 20, 2017 3:15 pm
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