Need Help w/ my '78 Hobbit

Hello, Thanks for reading my post. I hope you can help. I have a '78 Honda Hobbit, or PA50II. I have two problems. First- It won't idle with out full choke on. I made sure the carbuerator was clean, I checked everything I could think of. As soon as you take the choke off, it will run good, but when you slow down enough it just shuts off, it doesn't idle.

Second- it doesn't start up all the time. There is no battery, so this can not be the issue. It has great spark. I don't know why this is. I hope you can help me!!!

idle pin(s)

tighten the idle pin or pins, some mopeds have 2...count the number of rotations when you tighten it.


Re: idle pin(s)

Yeah, I tried that. I couldn't get that to help. It's almost like it's not getting enough gas, because it will idle fine on full choke. I pursued this by cleaning out the carbuerator. Then I thought maybe the muffler was clogged, but it was clean also. Then, when i took off the carbuerator, I found out that the spot where it connected wasn't flush. So i filed that down, and then I also made a gasket to make sure there were no air leaks. None of this helped!! I am desperate!! please tell me if anyone else has sugguestions

Re: idle pin(s)

something maybe stopping the gas from getting to the might be clogged in the tube

Re: idle pin(s)

I just had a thought. When you say idle "pin", do you mean the screw that sticks out that you can turn with a screwdriver?? That is called an idle screw, not pin right??

Re: idle pin(s)

nope...thats called a idle pin (i think) ive never heard anyone call it a idle screw, but its the same thing

its still a dirty carb

anytime a motor runs with the choke on .. but not when its off ... its a clogged fuel passage in the carb

On a PA you have to push out the brass 'emulsion tube' above the main jet and clean it too.

AND YOU HAVE TO USE COMPRESSED AIR!!! .. to blow the carb out

go to 'the guide' and follow the instructions very carefully

Also ...make sure the petcock flows good... and install an inline fuel filter with a paper filter element

They're called idls screws !

On a Honda PA .. there are two

There is an idle SPEED screw.

and an idle MIXTURE screw.

They are not called PINS ... only you call them 'pins' dave

Re: They're called idls screws !

lol ok sorry........but this is the first time ive heard them called idle screws, even a few motorcyclist i talk to call them idle pins....and everyone around here with mopeds calls them idle pins.

Re: They're called idls screws !

david f martin /

I can see that. They are needle shaped.


Re: Need Help w/ my '78 Hobbit

i would try setting the air mixture screw so it's almost all the way out, and then fiddle with the idle screw so you get the proper speed. it worked like a charm when my pa50II wouldn't idle.


Re: its still a dirty carb

Thanks for your sugguesion!! I think I will try this, but my question is how do you remove the "emulision tube" for cleaning??

Re: its still a dirty carb

It inside the carb above the main jet ... I take a thin piece of metal and custom bend it .. (almost 90 degrees .. like maybe a stiff coathanger).. to make a pusher .. to reach inside the carb throat and push it out the bottom.

Re: its still a dirty carb

thank you

Re: its still a dirty carb

I took your sugguestion and took out that jet and cleaned it. It didn't have very much "gunk" in it. I tested it anyway, but it still didn't idle. Then I checked my manual, and it says the points should be closer than they were. I fixed that, because I thought that maybe at low speed, there wasn't enough spark to keep it running. It would have worked with choke on, because a richer mixture is easier to ignite. I pretty much know for a fact now that it ISNT the carbuerator. I sprayed cleaner in all the different areas, and cleaned everything out. Is there any small possibility it could be anything else?? It seems that I have done everything and nothing helps the fact that it won't idle. I NEED HELP.

Re: its still a dirty carb

What is your idle mixture screw set at ?

Did you use compressed air .. (like at least 80psi).. to bow out the carb passages ?

Re: its still a dirty carb

we have checked all different settings, from all the way in to all the way out. yes, we did blow it out with our air compressor. since you responded so soon, i am guessing you are online, is there a name i can Instant Message you at? Also, I think it might be the reed valve

Re: its still a dirty carb

well, i guess you are not online. next time you are online, Fred, try IM'ing me at Battlebotz588 or Emailing me at I appreciate how much you have helped me so far, but i feel if I could talk to you in an instant message, I could explain to you better what's wrong, and it would be faster.Jake wrote:

Re: its still a dirty carb

We went out for a few hours on the boat.

I don't do IM'ing.

I have never ever seen a reed valve actually cause a "won't run" problem .. and there's almost never anything wrong with the reed valves.

.. seen lots and lots of people say.. "it must be the reeds" .. they buy new ones .. oops .. same problem as before.

You can take a look at them though .. hold the reed 'block' up to your mouth .. if you can breath air out .. but can't suck air back in... then the reeds are fine.

... if it runs with the choke on .. and won't run with the choke off ... it is not getting enough fuel ... it's STILL a dirty clogged carb passage.

... thats why 'the guide' says the best way is to buy a 'dunk-can' of carb cleaner and let it soak for a day or two ... THEN carefully blow it out with high pressure air.

orrrr ... take the carb to a motorcycle dealer and pay them to "boil" the carb ... they don't actually boil it ... but they put in their carb cleaner solvent tank for a while .. prob $5 or $10


your air filter element is still in though isn't it ?

(the little black cartridge with the foam insert .. accessible under the belt cover)

PA's won't run right with it removed.

(and will need the choke)

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