Motor starts, but stalls right away

brobie

New Member
Aug 15, 2008
22
0
0
Thanks to the help I received on this forum, I finished my build today and tried out my bike. I pedaled and then released the clutch and gave it a little gas. The motor started and sounded peppy, but died almost immediately. I am wondering if I quit pedaling too soon. I tried several more times with the same results. Any ideas where I can start troubleshooting this problem?
 

stude13

New Member
May 28, 2008
404
0
0
north bend wa.
hi, usually i start looking for spark, you have spark, next is fuel. you have enought to start it. i would start looking at supply of gas.
 

Motormac

New Member
Sep 23, 2008
108
1
0
Ontario Canada
This really looks like a fuel delivery problem to me, disconnect the fuel line at the carb and see if fuel flows out when the petcock valve is opened.
 

brobie

New Member
Aug 15, 2008
22
0
0
Hi Guys,
Thank you for your suggestions. I do have gas flowing to the carb. Today I disassembled the throttle assembly to make sure I had the ring on the needle valve on the second groove from the bottom. Put everything back together and tried the bike again. It ran for a little longer. We live in hilly country so I took it to a nice downhill area, got the motor going pretty good, but then it threw the chain. I am going to tighten up the chain tomorrow. I did notice that the chain tensioner guide wheel doesn't seem to go around. If I tighten it enough to keep it in place vertically, the wheel doesn't turn. If I loosen it up so the wheel can turn, it slips down in its slot. I am thinking of just removing the cussed thing, and take links out of the chain to make it tight enough and then if need be, use the tensioner on the pedal side. Any ideas on this?
Tyrslider, I did have the choke lever up, I thought that was the position it was supposed to be in for a cold start. Is that not right? I did try it with the choke in different positions, but it didn't seem to make too much difference.
 

Motormac

New Member
Sep 23, 2008
108
1
0
Ontario Canada
Ok did you check the needle valve in the carb, it might have dirt clogging it..especially if this is a new build with all the crud in the tank. Take the fuel bowl off and if you look up in the carb you will see a pronged fork, this moves a little black needle valve up and down, very carefully remove the prong and needle and shoot a jet of carb cleaner into the hole where the needle was.Open the gas and see if gas comes thru the hole now.Try this and report back.
 

brobie

New Member
Aug 15, 2008
22
0
0
Hi Motormac,
I did blow out the tank with compressed air before I installed it, but there very well could still have been something in there. I will follow your suggestions with the carb and let you know how it goes. Thank you for your help.
 

comfortableshoes

New Member
Jul 22, 2008
606
0
0
Beverly, MA USA
I had the same issue when I first got mine going, it would run for about 30 seconds and die out. I flipped the carb lever to half way, plunged the h311 out the side button and adjusted the idle mix to 1.5 turns out.

After that she starts every time I try to start her and goes no more stalling.

I also found that the cheap a$$ petcock is on both when the lever is pointed to the on label as well as when the petcock is pointed to down directly opposite of the on label. Guess what, I get better fuel flow when pointed opposite from the on label.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
237
63
up north now
I had the same issue when I first got mine going, it would run for about 30 seconds and die out. I flipped the carb lever to half way, plunged the h311 out the side button and adjusted the idle mix to 1.5 turns out.

After that she starts every time I try to start her and goes no more stalling.

I also found that the cheap a$$ petcock is on both when the lever is pointed to the on label as well as when the petcock is pointed to down directly opposite of the on label. Guess what, I get better fuel flow when pointed opposite from the on label.

Good starting technique....however the idle screw is for speed, not mixture.

Very good point about the petcock. Don't just ASS-U-ME that because it's pointed the "right way" it's flowing freely. Turn it with the fuel line in a jar and WATCH the fuel flow and compare it to the petcock lever.

I have had one that flowed good in the "Off" position, barely at all in the "on" position.
 

brobie

New Member
Aug 15, 2008
22
0
0
Hi all,
I checked the petcock on the tank first and it seems to be working correctly. I only get fuel flow when the long part of the rod is pointed down. I got the chain unjammed and reinstalled it tighter. Then I removed the carb bowl. Here I ran into a little problem, I saw the forked thing, but I didn't know exactly how to remove it. I can understand why Motormac said to remove it carefully; it looked pretty delicate. I could see it moved on a hinge -like rod. How does it come out? I sprayed a little carb cleaner up there anyway, but I suppose it won't do much good with the needle in place.
Had a little trouble getting the bowl lined up to put it back. Have a feeling I will be using my gasket paper in the near future. I should have said that when I disasembled the throttle the other day that the original setting was with the clip second from the top,and I moved it to second from the bottom. It didn't seem to make much difference.
I didn't get the chance to try out the bike after I took the bowl off. No reason to believe things will be any better since I didn't get the needle out. Tomorrow I will try it using Comfortableshoes method. I noticed that it did seem to run better after using the tickle button 5 or 6 times instead of 1 or 2. If this doesn't work, I will take the bowl off again once I find out how to remove the forked piece and spray the carburetor cleaner into the needle hole. Thanks to all who made suggestions. They were all very appreciated. It is great to have such a helpful bunch of people to rely on.
 

Motormac

New Member
Sep 23, 2008
108
1
0
Ontario Canada
Sorry Brobie, i should have mentioned that the prong is held on by a thin little pin in the hinge. This little pin slides out therby freeing the prong. The prong and the needle will come out,pay attention to the way the prong comes out so you can put it back correctly, do this very gently and do not lose any of the small parts!! Now spay in some carb cleaner into that little hole.
Now, while you have the carb apart very gently bend the outer ends of the prong downwards towards the float bowl about 1/16 to 1/8th of an inch. Reassemble it and see if it runs good. Let us know!
 

brobie

New Member
Aug 15, 2008
22
0
0
Hi all,
Well, I got the little pin out that holds the forked piece that holds the needle and squirted carb cleaner in the hole. I made a new gasket for the bowl because the old one was leaking from all the monkeying around with it I did yesterday. The new gasket took care of the leak. Then I used Comfortableshoes starting method and we took off pretty well. Then the $#@%^ chain came off again. I didn't take the chain tensioner off yet and it moved inward and caused the chain to come off. Tonight I am going to read over the instructions that were posted about getting rid of it. Thanks to all of your suggestions I think I could have had a nice ride if the chain had stayed put. Although this is frustrating, I do like the idea of having something relatively simple (as compared to my maxi-scooter) that I will eventually understand and be able to take care of myself. I have been wanting to put a motor on a bicycle since I was a kid and thanks to this group I have done it. Now if I could just get the chain correctly positioned and tensioned, the fun could begin.
 

Motormac

New Member
Sep 23, 2008
108
1
0
Ontario Canada
Good for you Brobie now at least you have it running,do you have the kind of bike that you can adjust the rear wheel back and forth a little bit? if you do you can get rid of the tensioner all together just shorten the chain and use the back wheel to tighten the chain. Let us know what you decide.:ride2:
 

jburr36

Member
Jul 17, 2008
285
0
16
Idaho
if you do you can get rid of the tensioner all together just shorten the chain and use the back wheel to tighten the chain. Let us know what you decide.:ride2:
If you are not careful the torque from the engine can pull the wheel out of alignment if the axle nuts aren't tightened properly. This happened to me once. The wheel loosened enough for the chain to jump off the sprocket and wrapped itself around the hub between the sprocket and the spokes. It took some effort to get it undone. I think the tension wheel helps keep the chained aligned on the sprocket.
 

ahalim

New Member
Oct 23, 2008
2
0
0
Fayetteville, Ar
Hey guys i am having the same problem with my motor. It starts up and then dies. I checked everything out. Spark plugs good. everything looks in order. Except what i think is that there is too much gas going into the motor that is why its choking. Gas had been leaking from the carborator too. Any suggestions as to how I get this thing started???
 

velardejose

New Member
Sep 9, 2008
120
0
0
Lima, Peru
Hi
I start with the choke closed, after a few secs I open it halfway
After a min or two I open it completely
I have the standard main jet, and the needle clip in the top notch
Peace
 

Dave31

Active Member
Mar 1, 2008
11,204
29
38
Aztlán, Arizona
Hey guys i am having the same problem with my motor. It starts up and then dies. I checked everything out. Spark plugs good. everything looks in order. Except what i think is that there is too much gas going into the motor that is why its choking. Gas had been leaking from the carborator too. Any suggestions as to how I get this thing started???
If you got fuel leaking from your carb, I would say you need to adjust the float. If the fuel level is not correct it would also cause your motor to receive too much fuel.

It is also possible that you may have some dirt or junk in the carb not allowing the float to work properly.
 

brobie

New Member
Aug 15, 2008
22
0
0
Hi all,
Well I seem to have the chain problem solved by buying a tensioner from thatsDax that has a roller bearing in it. Everything is much smoother and the chain is staying on.
Now motor is dying out again. It starts as soon as I release the clutch lever, but as soon as I quit pedaling it dies out. Before I was thinking that the chain coming off was what killed the motor, but now it appears that the two events are unrelated. I am also curious about the throttle handle. It seems to me that it doesn't move very far. I am probably comparing it to my scooter, but it seems like there is not much range between giving all the gas possible and not giving it any as far as the throttle hand control goes. Maybe I still don't have that assembly right. I am anxious to get this thing running before the snow flies. I guess I could try moving the clip on the needle of the throttle assembly. It is in the second from the top. Have also tried it in the second from the bottom with no difference.Which way does the needle work? Does the top position allow the most or the least fuel to flow? Any and all suggestions are welcome.