It wont stay running

[Desert Rat]

I own a 1985 Honda trail 110. after sitting quite a while, it would not start, I removed the gas tank and carburator to clean due to old gas. I disassembled the carb and jets for a complete cleaning and it still will not run. Adjusting thecarb per the manual, it will idle high, then just drop down and stall. I cannot adjust it to idle.
Air screw is set to 1.5 turns, brand new air cleaner, and no resin in the tank. Any suggestions?
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Desert Rat

[stinkwheel]

I would check the slow running jet again just to be sure.

Consider, did you reassemble the carb correctly, has the throttle needle become detached? Did you put the throttle valve back in the wrong way round (cutout should be to the rear)?

It could be drawing air round the inlet manifold.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Desert Rat]

It is assembled correctly, I inspected the jets, all appear fine and intact. However, I am unable to check the height of the float bowl (plastic), the float jet is rubber tipped and appears to be in good condition. I am trying to locate another carb but it is hard to find.
I think i will disassemble once again for another inspection. do you recommend dipping the carb in carb cleaner? Also, is it possible that the exhaust pipe is restricted? The spark arrestor at the rear of the muffler is removable, but is stuck and wont come out.

FYI, I own several motorcycles that up until now have all ran perfect, I do not know what I have done, but will continue trying.

Thanks for you input!
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Desert Rat

[stinkwheel]

You need to take the jets out and blow them through with compressed air. Having sat for a while that "varnish" may have bunged up the hole in the middle of the jet, the slow running jet is going to be very small as it is on a bike that size. Look at a bright light through the jet to check the hole is clear and round.

As I said, another possibility is that the engine could be drawing air at the inlet manifold. If you can get it ticking over at any speed, try spraying WD40 over the inlet area (between the carb and the engine), if the engine revs up when you do this, you have an air leak. (carefull if engine is hot, fire risk!)

If that all checks out, maybe not a carb problem?
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Desert Rat]

My apologies, I forgot to mention it will start first kick with choke closed and even run, it idles high, but runs, once the choke is off it will not remain running.

Ok, so I have assured the jets were clean, I went ahead and sprayed carb cleaner in all passageways with the carb disassembled to verify no blockages. All seams to be clear. since I cannot adjust the float bowl assembly because its plastic, will this cause the rpm fluctuations?
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Desert Rat

[wisebeuy]

ok, this might be a long shot, but if your saying that the bike will only run when the revs are high, have you considered that the spark might not be very good/timing slightly off. Electronics do not like being left alone for long periods of time.

[Desert Rat]

Have not checked timing - don't know how!

I would need to take to a repair shop. But why would it run better with the choke on?
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Desert Rat

[loply]

Fuel line kinked?

[Robby]

Sounds like a classic air leak to me, and at that age the carb rubber is no doubt a bit perished.

Blow the jets through, then reassemble. Check there are good tight seals at each end of the carb rubber, and use a hose clip at the carb end.

Or just get a new one.

[Desert Rat]

Fuel lines are new. Some time ago I had to replace the petcock due to leak......the new petcock is installed upside down because it is the wrong model, but the only one I could locate. This causes the fuel lines to be fed to the petcock between the intake manifold and the cylinder head, I thought it could be causing the fuel to heat, but this condition is present even when cold. fuel flow to the carb is fine. Perhaps the carb is drawing air in from somewhere it is not supposed to, most logically at the intake manifold. I replaced all the jets about a year ago, but the float was not part of the kit. I would like to locate a rebuilt carb, but they are quite hard to find.

I will check again for air leaks, that makes sense, because it will run with the carb choked.

Thanks,
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Desert Rat

[Desert Rat]

So I ended up buying a brand new carb from Honda. $200.00 (us dollars) OUCH!! But it fired right up and ran like a honda should run. Its such a little bike but fun to have around, thanks to all who participated in helping me.

Ride on, and be safe!

C-YA!
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Desert Rat