Lexmoto hunter 50 starts but doesn’t run

[Mr W]

Hi I purchased a second hand Lexmoto hunter 50 for my son as he has just turned 16. It has been running fine until the last few days where it wouldn’t start, we changed the HT lead, the bike now starts no problem, but will not continue to run, can anyone suggest anything to try to fix the problem please?

[Benni]

Hello W,

when it stops running, check the spark plug, it might be very dry,

I would think "no fuel", check the tank ventilation (cap off), how long was the bike out of use before you bought it ?

Carburetors do not like long periods of non-running / storage, fuel gets "off" and crystalizes or gums up the very fine passages inside the carb.

[freddytin]

Common issue on the Lexmoto is the side stand cut -out switch. In my opinion it's best removed altogether.

Another problem I've encountered is dodgy plug caps,. Did you change the cap with the lead ?

On the bright side most of the spares are incredibly cheap

Is yours carb or injection?

[CAPP0]

If it's carb, and it's been standing, my money would be on a bit of crap stuck in the main jet (which is why it'll start but not run).

[Don W]

Hi guys, I am new to PH. A few days ago I posted about my sons lexmoto moped which would start but not run, about 3 of you kindly responded with the suggestion that it might be worth having a look at the carb, which I did, in the bottom of it there was quite a lot of crud which I cleaned out, I also rodded the little tubes inside with cocktail sticks ( I should say at this point that there are only two things I know about engines 1) nothing and 2) f**k all) I put it all back together, pressed the starter and the little engine roared into life (we’ll roar might be an exaggeration but you get the gist) my son rode the bike for about 10 miles, stopped for several hours and then rode home with no problem at all. However next day we appeared to be back at square one again, engine would start but not rev above about 3000 revs. Has anyone got any further suggestions that might help me get my son back on the road? Or is it time to take it to a professional? Thanks in advance, and what a great site!

[Funky Squirrel]

Have you checked the carb again? If there was dirt in the fuel tank then it might have gummed it up again.

[Rubin215]

Don W said:

Hi guys, I am new to PH. A few days ago I posted about my sons lexmoto moped which would start but not run, about 3 of you kindly responded with the suggestion that it might be worth having a look at the carb, which I did, in the bottom of it there was quite a lot of crud which I cleaned out, I also rodded the little tubes inside with cocktail sticks ( I should say at this point that there are only two things I know about engines 1) nothing and 2) f**k all) I put it all back together, pressed the starter and the little engine roared into life (we’ll roar might be an exaggeration but you get the gist) my son rode the bike for about 10 miles, stopped for several hours and then rode home with no problem at all. However next day we appeared to be back at square one again, engine would start but not rev above about 3000 revs. Has anyone got any further suggestions that might help me get my son back on the road? Or is it time to take it to a professional? Thanks in advance, and what a great site!

The little tube things are the jets/emulsion tubes; do NOT start sticking things up them, they don't like it.
Usually, the jets are removable with care (either a slot for a screwdriver or a small bolt head) and you can blow them through from the other end with compressed air.
Google or youtube motorcycle carb rebuild and have a look at a few videos to help you.

If there is crud in the fuel tank (rust particles, paint flakes, dirt etc) it will always get back into the carb unless you clean the tank out properly and fit a fuel filter in the hose from the fuel tap to the carb.

[Benni]

There might be ( condensation ) water in the fuel tank, is will collect at the bottom because it is heavier than gasoline.
Because of that, it will be drawn down into the carb and then the water might clog up the fuel jets and passages,
because it has a lower viscosity than water.