2020 Bashan Motomax 250 gas leak

[johnnylaredo]

Thanks to this forum, I learned about and was able to get a very slightly used Bashan Motomax 250 from a great fellow Forum member.

I am a brand new motorcycle owner, and I have used the Motomax as a daily commuter to work (about 20 miles total a day about 3 times a week). I have put about 350 miles on it and, for the most part, it has been great.

I am not very mechanically inclined, but I have managed to do some fixes. The only real issues thus far were that the rear brake stopped getting pressure but (thanks again to this forum) I was able to flush it which seemed to do the trick. I was also able to switch out the headlight for an led one.

Today, though, I took it to work and when I got out I noticed a puddle of liquid under the motor. It was gasoline.
I rode it home, and parked it. A little later, there was another gas puddle. I switched off the petcock and the leak stopped.

The gas leak seems to be coming out of a single hose that is just hanging down from something attached to the carb area?

As can be seen from the pictures, behind the carb, and near where the petcock is (but on the other side) there is a hose which just hangs down unattached at the end. Is this normal?
I confirmed that this is where the gas is coming from.

The only unusual thing I have done recently is that I ran out of gas coming home last time (the Motomax doesn't have a fuel gauge, just a trip counter). I managed to put a little gas and rode it to a gas station. Up to now, I had been putting in ethanol free gas. As it was not available this time, I just put in premium and topped it off. I am not sure if that could make a difference.

Assuming it is not a petcock leak (because it stops when the lever is closed), does anyone have an idea of what it could be. Is it something that needs to be fixed or should I just close the petcock everytime I get off the bike? And, why would it just start now?

Any help would be appreciated - thanks!

[Frag2]

The float is probably stuck not cutting off fuel. the hose is a drain for carb when over full.

[herbie]

It's hard to tell because the image isn't very clear but it looks like the carb bowl drain screw is backed out. Try screwing it back in.
On the third picture it's the screw you can see at the lower part of the carb, it will drain the gas if it's opened up.

[China Rider 27]

Originally Posted by herbie

It's hard to tell because the image isn't very clear but it looks like the carb bowl drain screw is backed out. Try screwing it back in.
On the third picture it's the screw you can see at the lower part of the carb, it will drain the gas if it's opened up.

I would second that it sure looks backed out allowing gas to flow straight through that carb. Sometime you need to put lock washers on those carb mounting nuts to head off a potential problem. I had one fall off while I was riding a couple of weeks ago causing engine misfire.

[Frag2]

I see its been corrected drain for carb see if loose screw. alzheimers

[Megadan]

Yep, bowl drain screw. If it is still tight, then I would suggest going through and cleaning the carburetor, paying close attention to the needle and seat for the float. You can also check/set the float height. If you invert the carburetor the bottom of the float opposite of the float needle side will not be the top of the float, and that edge should be 14mm from the bowl flange on the carburetor.

[johnnylaredo]

Thanks everyone so much for response.

I guess I didn't realize that whenever I park my bike overnight I should turn off the gas. I assumed it was like a car and only needed the gas off if stored for a couple of months.

Regarding the carb screw, I am not sure which one it is. I have attached a picture. I understand that the top one (the gold one) is the idle screw. Is that the same thing?

Thanks

[Megadan]

If you park the bike qith the fuel on and its leaking out fuel then the float needle is not sealing against the needle seat and likely needs to be cleaned or otherwise replaced. Good way to fill the motor with fuel and hydrolock the cylinder if it gets bad enough.

To answer hour question, number 2 is the bowl drain screw.

[TheChairman]

Screw #2. That's the carb drain screw.

In your photo it looks a little knackered, like someone tried to tighten it down before. Maybe for the same issue.

I'd be having a look there. I've seen those get overtorqued and leak, and I've seen a corroded seat cause a leak. That screw is actually a needle valve.

[cycleway4]

#2 is the carb bowl drain screw....it just needs to be seated in tight.

the purpose of the screw,...is if you were letting the bike set for an extended period of time,..you could first turn off your fuel tank petcock,..then open the #2 screw,..and drain your float bowl.

[johnnylaredo]

Thanks everyone. The screw does look like it was stripped or something. I think I have to remove the exhaust to get to it, but I will and see if it can be tightened.

Is it something I can remove and replace, or would I have to take out the carb to work on it?

Thanks again for all your input!!!

[duck9191]

I would take the carb off vs screwing with the exhaust. that way you can check the float needle and seat while you are at it. Also, it gives you a chance to see how the inside of the carb is looking and clean it if it needs it.

[TheChairman]

I'm not 100% versed on the carbs used in these bikes yet.

I had an older Keihin from a Honda Twinstar that had float bowl issues. I went on eBay and bought a cheap counterfeit carb and used that float bowl to replace the bad one on the Keihin. Worked a treat, and was much cheaper than buying a new carburetor or in this case, paying for used stock.