Problem starting Scooter Clone Yamaha YP250 By rock71 (Read 2,729 times)

[rock71]

Hello, How are you, I come over here to see if you can give me some help.
            I have a serious problem with my Scooter skygo Executive 250 (Clone Yamaha YP250), when going uphill the bike turn off and then when I try to turn it on again the RPM not go beyond 1500 and if I try to accelerate it goes off , after a while I let rest a few minutes and turn it on, RPM gets 2000 and everything ok again , I commented that I have done so far, because it is a failure that came from the factory, the bike is new, I got it with 7 KM only.

1) at first,  I realized that there was no flow of gasoline or was blocked, whereby a small hole was opened in the mouth of the tank to give relief.
2) the valves were adjusted 0.10mm (intake) and 0.18mm (exhaust),  maybe get stuck again ...?
3) I  change the oil every 1000km, currently has 3100 Km, I put the oil 1.3 liters at each change ( 20w-50 ).
4) I also have change and 3 NGK Spark Plugs ...

Any recommendation is welcome, Thanks!

[ellpee]

Agree sounds like "fuel starvation" when you accelerate and go up hills. Poor vacuum connection to fuel pump? Clogged jets from bad gas? Kink in a fuel line somewhere? But others here will give better advice.

My contribution is, it sounds like you may be putting in too much oil, nothing to do with your primary problem. My Honda clone only takes about 0.8 liter. Yahama clone may be different, however, so don't go with that without further advice.

[rock71]

 Thanks you for  your response, About the oil, the Yamaha YP250 Manual service says 1.4 LT, but given is a Chinese Clon I just put 1.3Lts , now about " fuel starvation " sounds like that, but the only additional thing that I need to review is the carburetor , here for me the fuel ratio screw  is difficult to deal with  , thescooterprofessor.proboards.com/thread/3001/4-stroke-carb-tuning,

[JR]

1.3 liter = 1.05 quarts and that is the correct amount for the Yamaha clone. Exhaust valve I would set back to 0.16mm and intake to 0.12mm but thy are close.

Have you pulled the carb and cleaned it? Also you need to make very sure all vacuum lines are tight and no leaks on the carb intake manifold and you have very good vacuum to fuel pump, you've got a vacuum leak which is not letting the fuel pump give enough fuel at a higher RPM or a partially clogged main jet in the carb?

JR

[ellpee]

Actually 1.3 ltr = just shy of 1.4 qt, but who's counting.

[rock71]

Mar 6, 2015 20:09:32 GMT -6 JR said:

1.3 liter = 1.05 quarts and that is the correct amount for the Yamaha clone. Exhaust valve I would set back to 0.16mm and intake to 0.12mm but thy are close.

Have you pulled the carb and cleaned it? Also you need to make very sure all vacuum lines are tight and no leaks on the carb intake manifold and you have very good vacuum to fuel pump, you've got a vacuum leak which is not letting the fuel pump give enough fuel at a higher RPM or a partially clogged main jet in the carb?

JR

Thank you, I'll do this tasks tomorrow

[rock71]

Hello Again,
In the past weekend I adjust the valves to .12mm (in ) and 0.16mm(exh), everything fine!, well during the week bike begun to lost a lot power, and I had to go to a mechanic to review what's happened, The trouble was the Camshaft Chain Tensioner was broken suddenly , The mechanic change this tensioner for new one and after the bike was running fine again.
The carb was cleaning and adjusted, and the relenti was set in 1300 RPM idle, now is running smoothly with very few vibrations, now my question is about Oil Change Quantity, The Owner Manual here in venezuela for this Scooter says 1.1Lts, the mechanic says that this bike need Oil change 1.5 LTS , and searching the Chinese scooter that selling in USA, my Model is equivalent to ROKETA MC-79-250. I'm truly confused here
Has anyone the owner manual for Roketa MC-79-250 in PDF Format ??, is to compare what maintenance is done in USA with this bikes ( Yamaha Linhai clone 250 ).

Here some photos from my Bike.














Thank you!

[rks]

Think I would go by the owners manual, rather than what someone told me.

I did find these specs for a YP 250......still think your owners manual is the best bet

YAMAHA YP 250 MAJESTY 4UC
Year of manufacture:
1995 to 1999
VIN:
-
Specifications*:

Engine size:

249
Cylinders:

1
hp/kW:

20/14
Valve clearance (intake):

KALT 0,08-0,12 MM
Valve clearance (exhaust):

KALT 0,16-0,20 MM
Engine idle speed:

1450-1550 U/MIN
Carburettor air screw:

1,9 AUSDREHUNGEN
Tyre pressure (front):

1,75 (2,0) BAR
Tyre pressure (rear):

2,0 (2,25) BAR
Spark plug 1:

NGK DR8EA
Spark plug 2:

NGK DR8EIX
Electrode gap:

0,6 MM
Fork tube diam.:

33 MM TELEGABEL
Front/rear sprockets:

-
Chain:

-
Capacities:

Fork oil per rod:

142 ML SAE 15W
Engine oil w/o filter:

1,2 L SAE 10W40
Engine oil with filter:

1,2 L MIN. API SE
Brake fluid:

DOT 4
Final drive oil:

250 ML SAE 10W-40
Fuel:

11,0 LITER
Coolant:

1,4 LITER

[JR]

rks ellpee rock71

It will hold a tad above 1L, refer to this video for a good reference on checking the oil, it works for all scooters.


thescooterprofessor.proboards.com/thread/4172/engine-exhaust-checking-level-proper

JR

[ramon]

Buenas  Rock71

Tengo una Skygo Executive 250 y me esta presentando problemas. 
Es mi primera moto y la compre de segunda mano, no se si ya venia con alguna falla oculta. 

La falla que presenta aparentemente es de bujia.  en dos meses me ha tocado cambiarla 2 veces. 
Primero  cuando estaba andando y desaceleraba , se me apagaba repetidas veces hasta que un dia no prendio... le cambie la bujia y  empezo a funcionar de nuevo. 
despues apenas a las 3 semanas la fui a encender y no prendio... otra vez cambie la bujia y  funciono..

Ahora,, dos semanas despues  y eso que solo la uso para ir a trabajar unos 15 km.  de nuevo falla y si no la mantengo acelerada empieza a corcobear y luego se apaga. 

Tendras algun mecanico de confianza que puedas recomendar? yo estoy en caracas. y como te comente al ser mi primera moto pues no se casi nada.  tendras alguna sugerencia? 

como la compre de segunda mano  tampoco tengo el manual...  sabes donde lo puedo conseguir.

Agradecido de antemano por tu respuesta.. 

Atte. Ramon

[ramon]

Good Rock71



I have a 250 and I SkyGo Executive is having problems.

It's my first bike and buy second-hand, not if and came with some hidden flaw.



The fault has apparently spark plug. in two months I have had to change 2 times.

First when I was walking and slowed, my bike several times I turned off until one day did not catch. I replace the spark plug and started working again.



just after 3 weeks I went on and did not catch ... again replace the spark plug and run, all fine .





Now after two weeks ,, and that only use to go to job about 15 km. Fails again and if I do not keep accelerated starts corcobear and then turns off.



You'll have some trusted mechanic you can recommend? I'm in Caracas. and as mention it is being my first bike because there is almost nothing. you'll have any suggestions?



as the purchase of second-hand I do not have the manual ... you know where I can get?



Thankful in advance for your reply ..



Atte. Ramon

[crwford]

May be spark plug wire is coming separated from boot pull off plug trying screwing the boot in tighter and try again or unscrew boot cut back 1/4 of wire and screw it back on then see. It seems every time you pull wire to put in a plug it runs for a while plugs last longer that that.

[ellpee]

Might want to see if you're getting a consistent, strong blue spark thru the boot. Take the boot off the plug, insert a nail or screw firmly enough that his has good contact inside the boot, then hold the nail close to the engine block or metal frame part and crank the scooter. (Don't touch the nail unless you like strong electric shocks!) If the spark is weak or yellowish, the plug wire or the coil or both may be defective.

Also, when you've replaced the plugs in the past, did they have a lot of black soot buildup on the electrode? My scooter was running way too rich when I first got it, and within an hour or so the plug would get so clogged with soot that it wouldn't fire.

[rock71]

Aug 25, 2015 21:10:14 GMT -6 ramon said:

Buenas  Rock71

Tengo una Skygo Executive 250 y me esta presentando problemas. 
Es mi primera moto y la compre de segunda mano, no se si ya venia con alguna falla oculta. 

La falla que presenta aparentemente es de bujia.  en dos meses me ha tocado cambiarla 2 veces. 
Primero  cuando estaba andando y desaceleraba , se me apagaba repetidas veces hasta que un dia no prendio... le cambie la bujia y  empezo a funcionar de nuevo. 
despues apenas a las 3 semanas la fui a encender y no prendio... otra vez cambie la bujia y  funciono..

Ahora,, dos semanas despues  y eso que solo la uso para ir a trabajar unos 15 km.  de nuevo falla y si no la mantengo acelerada empieza a corcobear y luego se apaga. 

Tendras algun mecanico de confianza que puedas recomendar? yo estoy en caracas. y como te comente al ser mi primera moto pues no se casi nada.  tendrás alguna sugerencia? 

como la compre de segunda mano  tampoco tengo el manual...  sabes donde lo puedo conseguir.

Agradecido de antemano por tu respuesta.. 

Atte. Ramon

Ramón , Gusto en Saludarte.
            a mi también en el principio me dio muchos problemas, varias veces me dejo varado en el autopista con mi esposa...imaginate el CARON de ella jeje...moto nueva y se apaga ... bueno después de varios intentos también como tu le cambie varias bujías....hasta que encontraron la falla, la misma esta en el Carburador, debes de limpiarlo bien, puede ir a Bello Monte detrás del centro polo, hay una tienda pequeña que también es taller y venden motos, pregunta por Marcos que es el dueño, de hecho todos ellos tienen la executive y casi todas presentan el mismo problema, ellos ahí te limpian el carburador pero cerciorate    que te lo monten bien de nuevo, son panas pero un poco descuidados.
             hay otro foro donde estamos varios Venezolanos, te invito a unirte: .foromotos.com/forumdisplay.php?f=222" rel="nofollow" target="_blank">.foromotos.com/forumdisplay.php?f=222

             Cualquier duda a tus ordenes.