Pleas..my scooter has problems :(

[chi]

Hi guys. My scooter is Piaggio typhoon 2019 50cc 2t

I installed it

Malossi 70cc bore kit (new)
PHVA Carby 20.2 with 95 MJ (will try with 85) ( New)
Yasuni R
Remove oil pump
Mixture 33:1

it was running very well but I got some damaged on Cylinder so I couldn't start it on because of low compression so I change new cylinder but there is some problem I don't know what is that. when I start it on, I tune the carby for rev around 1700 but after few minutes, rev is going up around 2000~3000 rpm and didn't come back down but sometimes it come back to stable around 1600~1700rpm.
anyway I tried test driving but first times it was ok but after 10mins drive , cut engine off during WOT(when I put the break on and when I wait for traffic, rpm going very low and cut engine off fews times)

and I pulled over my scooter and tried start scooter but I couldn't just cranking so I did kick starter and it works but it stall fews times when I wait traffic too. I tried to put smaller MJ but same problem and one of my friends said, Maybe fuel system problem so I put New Fuel tap and checked it but it looks fine.    I tried every things by myself but I can't find it what's problem... 

Need help.. please ... it is very good weather outside ... want to drive side of beach... 


That is my Checked list

Fuel lines
Carby is New but did clean up 
Good spark plug ( it was black so look like rich so I put smaller MJ)
Good compression coz of new Cylinder 

[geoffh]

That's a big ol carb you have put on there,I would try the old (presumed smaller) carb but with the jet upsized to cover the extra 20% you have installed.

Geoff

[aeroxbud]

Sounds like you have an air leak.
The stock carb would be fine with the setup you have.
Which Malossi kit do you have? You can't use the kit for the older models on the Euro 4 models. Are you still running the original Piaggio head?

[chi]

Dec 14, 2023 18:54:22 GMT -5 aeroxbud said:

Sounds like you have an air leak.
The stock carb would be fine with the setup you have.
Which Malossi kit do you have? You can't use the kit for the older models on the Euro 4 models. Are you still running the original Piaggio head?

My model is Euro4 and It’s Malossi sports 70cc and put Malossi head

[chi]

Dec 14, 2023 16:14:44 GMT -5 geoffh said:

That's a big ol carb you have put on there,I would try the old (presumed smaller) carb but with the jet upsized to cover the extra 20% you have installed.

Geoff

So you mean . Try put smaller MJ??

[aeroxbud]

You need to run the stock head with the Malossi special gasket. Your ignition timing is going to seize the cylinder.
This video explains why.

[chi]

Dec 15, 2023 5:48:22 GMT -5 aeroxbud said:

You need to run the stock head with the Malossi special gasket. Your ignition timing is going to seize the cylinder.
This video explains why.

Thanks mate. Maybe that problem. I will try put factory cylinder head with temperature sensor.

[aeroxbud]

Just make sure you use the proper gasket. Otherwise you will damage the piston.
Good luck.

[chi]

Dec 16, 2023 7:26:58 GMT -5 aeroxbud said:

Just make sure you use the proper gasket. Otherwise you will damage the piston.
Good luck.

I put the other head with temperature sensor but when I full open throttle , suddenly cut engine out.. still same problem

[chi]

Dec 18, 2023 1:06:19 GMT -5 chi said:

Dec 16, 2023 7:26:58 GMT -5 aeroxbud said:

Just make sure you use the proper gasket. Otherwise you will damage the piston.
Good luck.

I put the other head with temperature sensor but when I full open throttle , suddenly cut engine out.. still same problem

After died scooter, I tried to start it but I couldn’t but only kick starter work.

[freeqsee]

First check reed valve and intake for any cracks and air leaks.
If everything looks fine, try to proper adjust the mixture. As you said, if the spark plug is black it's too rich so give him more air.
Also, what type of choke do you have? If it is an electric one, disconnect its cabble and start the engine without choke and see what happens.
Maybe this video will help you to proper adjust it: www.youtube.com/watch?v=A1vRMERs4RQ&list=PLRaS4DonNXQneGPDEmM6vn4TjCfMCEC9P&index=1

[chi]

Dec 18, 2023 1:52:16 GMT -5 freeqsee said:

First check reed valve and intake for any cracks and air leaks.
If everything looks fine, try to proper adjust the mixture. As you said, if the spark plug is black it's too rich so give him more air.
Also, what type of choke do you have? If it is an electric one, disconnect its cabble and start the engine without choke and see what happens.
Maybe this video will help you to proper adjust it: www.youtube.com/watch?v=A1vRMERs4RQ&list=PLRaS4DonNXQneGPDEmM6vn4TjCfMCEC9P&index=1

It was rich with MJ 95 so I put MJ88 and look nice after test driving but it was died when WOT for few minutes and then It couldn’t start on . Only work with kick starter.


My scoot has E-choke. I tried disconnecting and was same issue.

[aeroxbud]

If you disconnected the choke, it would be permanently on.
If you did not have the special Malossi head gasket to run the standard head. The piston will hit the cylinder head.

[chi]

Dec 18, 2023 1:52:16 GMT -5 freeqsee said:

First check reed valve and intake for any cracks and air leaks.
If everything looks fine, try to proper adjust the mixture. As you said, if the spark plug is black it's too rich so give him more air.
Also, what type of choke do you have? If it is an electric one, disconnect its cabble and start the engine without choke and see what happens.
Maybe this video will help you to proper adjust it: www.youtube.com/watch?v=A1vRMERs4RQ&list=PLRaS4DonNXQneGPDEmM6vn4TjCfMCEC9P&index=1

If it works well with disconnected e-choke, can I keep disconnected and without choke ??

Yes I put special gasket with factory cylinder head. I will try disconnecting tomorrow and will be back. Thanks

[aeroxbud]

It's a different gasket to the one that came with your cylinder. It's thicker.