Won't start 2

[Mike Horton]

It appears I need to check out the carb. The bike will just not start. It was running perfect a day before it was shipped. I think draining the gas from the tank and carb did something. So, what is the easiest way to check out the needle and seat. Do i have to take the carb off ? Can i disconnect it on both ends and rotate it so I don't have to disconnect the cables ? Can you remove the slide with cables connected and let them hang carefully ? Sorry for asking so many elementary questions, but i don,t want to screw this project up. thanks mike

[Dennis D]

Mike, If you have clear fuel line on the bike you can see if it is flowing into the carb when you use the tickler. If you can't detect any flow try tapping on the float bowl with the plastic end of a screwdriver. If the needle is hanging up in the seat sometimes this will jar it loose. It's worked for me! Dennis D

[Big Mac]

Mike- Every once in awhile, I've had similar fits with my 250 with Bing carb. Will blurp for a about 3 seconds then just stop, and back to kickety kickety kickety. Even pushing and bump starting didn't get it and only a few more short blurp runs even with fresh plug.

After flooding the tickler again and again with no luck, I finally figured out that it was over-tickled and too much fuel was in the bottom end. On the 250/400 motors (assume same on 175s) there's a drain screw, w/ hex head 4mm I believe, between the fins on the bottom of the cases at lowest spot below the crank. If you unscrew this drain screw and a couple of teaspoons of fuel run out, you're probably having the same problem. Try draining, then tighten it back up plenty tight, then try pulling the plug, shut the fuel taps, open the throttle to allow plenty of extra air and kick it through a bunch to dry it out.

At that point, I've walked away from it for a few hours and got my wind back, then got it to light off no problem later with a few good kicks. No problem starting since then.

You can work on the float needle, jets, etc in the Bing easily by loosening clamps on front & back, rotate it away from pipe so you can easily get the carb top screws loose, pull the carb top loose but leave the slide down in the throat of the carb--pull it all the way out and let it hang free if you must, but once out, it's a pain for me to get the slide back in since the needle always wants to hang up on the needle jet and I end up having to pull the air filter, reach through and wiggle that sucker to get it to drop back in place. Just taking the carb top loose and letting the spring & cable stretch out with slide staying put gets enough slack to rotate far enough.

I can get most all done from the left side bottom with carb rotated over until it bumps the right side engine strut. Take off the strut and you can get it all the way sideways to make things even easier. If you slide off the carb bowl and a bunch of fuel spills out, you can bet that starved for gas is not the problem. A full carb bowl will run close to 3-4 minutes at idle pretty easy. Good luck.

[crash carden]

Hello Mike,I would try Dennis's little test first,if that does not work you can remove the top of the carb with the cables connected and let them hang. First loosen both ends of the carb and tilt it so you can remove the top. Then I pull it out by the cables making sure I have tenion between top of the carb and the cables so they don't slip out of place. To be on the save side I cover the slide and top of the carb with a small plastic bag to keep them clean,and rap some tape around the top of the carb where the cables go through the guide holes. This holds the bag on and keeps the cables from moving out of place. As long as you keep some tention on the cable's as you move them about they should stay in place.Then you can just remove the carb and see whats going on. Hope this helps you out,this is how I do it and it works for me. Good luck, Crash Carden - GO TEAM PENTON!:D

[crash carden]

Hello again while I was typing my idea, Big Mac posted his and it sounds like the best plan. Good post Big Mac, I learned some new tricks [^]Thanks Crash Carden.

[tomale]

Mike do not worry about asking "elementry" questions. We were all there once. And we all can learn a thing or two. I for one like to take the carb off and check it out because you never know what it is truly like. Taking a look see to the inside of the float bowl will tell you alot about the condition of the bike and how it was stored. If you do find signs of varnish then it is time to check the tank as well. When a tank is left empty and it dries out, if there is any varnish it dries out too and when fresh gas is put into it the harded varnish comes off and can and often does plug up the petcocks. If you are not getting a good flow of fuel. this would be my guess as to the reason. I think you are right about the fact it was shipped empty had an effect on your problem now. but then sooner or later you would have to deal with it anyway. Also. These old tanks do not do well with leaving gas in them. Todays fuel eats the inside of the tank and it is best to empty the tank after each outing. It will not happen over night but if left unattended the tank will begin to leak. I suspect that the first place will be around the petcocks because it is the place when the fiberglass attaches to the metal insert that the petcock screws on to. It becomes a week point. Not to worry even if it does leak a bit... it can be fixed and with not too much effort or cost.
Hang in there, you will get throught this, you are in good company!
If I had had this kind of support 25 years ago I may have never quit riding when I did. And they are responsible for be to continuing to ride now. Its that old thing that has to do with Money and lack of time or lack of money but plenty of time. Some where in the middle it would be nice if they could meet or at least wave at each other.

Thom Green,Still crazy after all these years!
76' 250 MC5 (orginal owner)
78' 400 MC5

[Steve Minor]

Try this site for some Bing tune up advice. I understand it's for ultralights, but the theory is the same.


http://www.ultralightnews.com/enginetroublshooting/techtips/techtips2.htm

[imported_n/a]

I went to Mike's house today to see if I could help him.  After removing the carb it was obvious that the pilot jet was plugged.  We took care of this, but noticed that the float needle was sticking in the seat.  Mike is going to order a new float needle, but can you replace the seat?

Mike just bought a '75 175, so he is going to switch carbs to check that his ignition is OK.

[hrbay]

The seat is pressed in, don't think it can be replaced, not easily anyway. The new needle will eventually seat itself but can leak a little till then. I have very lightly tapped 'old' float needles to reseat them in the brass seats. Good luck.

GC

[Kip Kern]

The seats can be replaced but it is a bit of work.  Contact Bing International and they should have some, I sent a few to Charlie.  I opt for the rubber tipped float needle and this seems to work pretty good.  Good Luck!