125CC Sinnis Harrier cuts out while riding/then won't start By dannus (Read 4,751 times)

[dannus]

Hi all,
Bit stuck with this one, i have a Sinnis Harrier 125cc Scooter, i bought it about 3-4 weeks ago, it was perfect to start with and very reliable. 
I put some new fuel in the other day, it was the right kind, but now it will cut out after a couple of miles, and then won't start up, not even with a kick start. However if i then leave it for a couple of hours or over night it will then start up again first time and off i go, but the same thing will happen again.

To be honest, i did not cover it until recently, i wonder if the wet weather may now be the cause?

I can go so fast and then it cuts out, not full throttle but just at a steady speed and then cuts out, no matter what speed i go it just happens.  If i am lucky enough to get it started after about ten mins it then will last maybe 4-5 mins before it cuts out again. 

At the end of the day, when first going on it, there is no problem, and even my friend thought i was a little crazy when i tried to explain this to him, but after a couple of miles it seems the worst scooter in the world.

I am not scooter savy when it comes to repairs or checking in the slightest, this is all new to me, i checked the part where the spnge is encase maybe this was wet but it was dry. There is petrol in the tank as i have visually looked inside the tank, is it worth trying to drain it and then putting new fuel in? This has become stressful ad i rely on it for work, ic an't afford for it to sit in some garage for days on end.

Thank you, any help would be greatly appreciated!

[cyborg]

Next time you fire it up and it dies crack open the fuel tank cap,,if you hear air rushing in it's a tank venting issue,,,,if it is just drill a very tiny hole ( read very tiny) in the cap and problem solved

[cyborg]

If that's not the issue ,,,the valve lash needs to be adjusted,,,,there are a couple of tutorials here and on other forums and YouTube as well for this procedure,,,don't panic it's not difficult to do,,,my grandma can do it and she's been dead for 30 years,,,easy peasy

[JR]

dannus

This is a new line on me but looks like the typical GY-6 set up and I do see they are Chinese:



Two things come to mind first. I'm thinking this is the problem but it could not be so we need to eliminate it, gremlins like this is a process of elimination, find nothing wrong testing one thing then eliminate it off the list.

Since you mentioned the fuel thing we need to see if you're getting good fuel flow. Question does it have a fuel pump or is the tank above the carb and it has a gravity flow system with fuel petcock?

Looking at the pictures I'm betting tank above the car gravity flow? When you got gas it's possible you got some poor gas with trash and/or water in it and the fuel filter is partially clogged and when the engine demands more full for higher speeds it is starving for fuel. Let it sit a bit and the fuel system fills back up even the carb bowl. Need to look at/change the fuel filter.

Secondly if the petcock is not opening good due to a vacuum leak due to a cracked intake manifold or a bad vacuum line the system again will starve for fuel at higher RPM's.

Also you need to check the fuel cap and make sure the tank is venting and getting a little air, fuel flow will be interrupted if the tank is not venting and it will create a vacuum that will not let the fuel flow properly.

Get back with us after you inspect these tings and if you need help doing just that let us know.

JR