Author Topic: honda express nc50 2 stroke  (Read 3851 times)

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Offline jakecb420

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honda express nc50 2 stroke
« on: March 30, 2010, 08:33:03 PM »
i have a 79 honda express 2, nc50. i rescued it from a barn, it hadnt run for probably 15 years or so. i have rebuilt the carb a few times (3 or so), found some broken ignition wires, and thats about it. new plug of course, checked points, good spark. the problem i am having is that it wont stay running unless i cover or partially cover the air intake on the carb with my hand. as it dies down, i can move my hand to allow more of less air in to keep it running. i have the air filter housing and all but the filter element itself. i rubber banded a piece of foam to the cage. with the air filter assembly on it wont even start. i am sure i am missing something but any help would be appreciated. it does run pretty good when it is running. could my air screw be that far out? i set it at the service manual specs. any kind of advise is appreciated. thanks
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Online bryanj

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Re: honda express nc50 2 stroke
« Reply #1 on: March 30, 2010, 11:11:42 PM »
Carbs were/are a nightmare on those. Pilot jet gets blocked easy and i think its pressed in like the 77 model 750 and 550 but they will extract with care.

Might be worth going the ultrasonic cleaning route as it aint big

PS air cleaner was only a lump of foam anyway
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline jhasewhite

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Re: honda express nc50 2 stroke
« Reply #2 on: March 30, 2010, 11:29:57 PM »
I ended up throwing a 12mm dellorto and a handmade manifold fabbed out of a aluminum bullhorn bicycle handelbar to get my girlfriends express reliable. There was something a little "off" with those things. Also check the oil injection, they get air bubbles and starve/flood the crankcase easily. Get a Hobbit, they are waaay better.
slow and steady does nothing.

Offline birdmannn101

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Re: honda express nc50 2 stroke
« Reply #3 on: August 31, 2015, 10:13:05 AM »
After all the bull crap of trying to get my NC50 to run I changed the spark plug and it fired right up.  Yes, the old one was still sparking.  I guess it got fouled with oil/gas mixture.

I even drilled out the pilot slow jets which I wish I hadn't done now since I need 2 more to get another NC50 running again.

Anyone got any extra pilot slow valves for sale???
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