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Open since July 17, 1999
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The sight glass on my nc50 oil tank leaks. Sure, I could run premix but the gas tank is now leaking into the oil and thus, I have a leaking tank. I plan to buy a coating kit for the fuel tank but does anyone have any bright ideas about the sight glass being resealed? I am trying to keep this bike as stock and original as possible and of course, a coating on the sight glass will hinder my efforts. The glass spins around pretty loosely, but the grommet that holds it in place does not want to pop out, and I am being careful not to break anything.
Posted on Jul 28, 2004, 8:43 PM from IP address 65.54.98.29
I recently inherited a 1986 Honda Aero 50. It has been in storage for about 10 years. I have cleaned the carb, drained the old gas and oil and replaced with new. I put in a new spark plug and tried to get it started. It started to crank and then got stuck. I could manually move it through the sticking spot. After a short time I decided to remove the spark plug and see if it was a mechanical hitch or compression. I turned it over a couple of times with the spark plug out and I was met with an eruption of oil. However, it cycled through without any problem. I tried to blow out as much oil as I could and eventually no oil was coming out. When I replaced the spark plug, it was able to keep cranking without getting stuck. However, it still would not start and everytime I removed the spark plug it was fouled with oil. I know that I am getting a spark. Any thoughts??
Posted on Jul 26, 2004, 8:55 AM from IP address 216.186.53.1
that's why the piston got stuck , it couldn't pump the oil..
now you have to clean the crankcase out..
there is NO quick easy answer here
start by unbolting the exhaust..
and removing the sparkplug..
you can try compressed air, or safety solvent or both..
you can HANG the scoot tail up in the air and hope to drain the oil..(just kidding) but elevating it might help the draining process..
untill you get all that oil out of the crankcase and clean it out of the exhaust.. that scooter isn't going to run.. it can't the oil is absorbing the gas and fouling the plug too.
the excess oil that is in the exhaust will cause too much back compression and can keep the engine from starting, and will definetly cause it to run slow
TheMopedWhiz
Ride Mopeds..SAve Gas..Have Fun
Posted on Jul 26, 2004, 11:31 PM from IP address 66.174.76.204
I cleaned out the crankcase using a combination of some solvent and a slight modification of a turkey baster. A tube with a rubber ball on top create some suction. It still wouldn't start, but the plug was no longer getting fouled. I tried spraying some starting fluid directly into the piston chamber and it started, ran for about 5 seconds and died. I repeated this several times with the same results. It seems as if it is not getting any gas to continue to run? I have cleaned the carb and put in fresh gas but I am not sure what else to do??
Posted on Jul 28, 2004, 8:34 AM from IP address 216.186.53.1
Tranny Help
I have a 1978 honda express that the tranny has been taken apart. The cover was taken off because the kick starter was locked, I guess. Now I can't put it back together. Any help will be appreciated. Thanks.
Brad
Posted on Jul 25, 2004, 3:11 PM from IP address 4.228.162.146
i have a nice nc50 and i just orderd the metrakit 64cc engine kit and the proma exaust. myu question is what should i do to protect against engine seiz or things i should know about the install/tunning to help this project go more smoothly. ive been reading the posts and i know that i should break in the engine first with premixing my oil to 20:1 but does this mean i should remove or not fill the oil tank for the oil injection? should i also consider re jetting my carb if so what size would you suggest? will i need to swiss cheese my airbox to get more air? is there parts that should be upgraded?
thanks,
1981 honda express
minneapolis
Posted on Jul 24, 2004, 6:45 PM from IP address 24.26.176.187
The first thing to get to "monitor" the engine is a head temp gauge. It is a ring that goes under the spark plug to monitor the head temp. This is a great tool to keep track of the jetting. As for my honda I refuse to go over 400 degrees F at wide open throttle. I hear it should average about 300F or so(cruising). Reading the spark plug by pulling it out after a few runs would be a great ideal, because that is the only component in the combustion chamber. You want a tan color, black/wet is fouling from too rich or too much oil. White is lean- this will cause siezing in no time! When breaking in you will be running very rich, so you may run a "hotter" plug to prevent a fouling plug... Good luck. Keep us posted! Aloha.
Bob
is this a stand alone system we can install on our peds..
where do we find one..
This message has been edited by themopedwhiz from IP address 66.174.76.204 on Jul 29, 2004 10:15 PM
Posted on Jul 27, 2004, 11:44 AM from IP address 69.75.15.63
I recently put together a dio motor with a 51.5 crank and 52mm piston. My piston is about .5mm below the deck. And I am getting a compression reading of 95 Psi. I tried to sandpaper the head a bit and got up to 105 (untill I was a ball of sweat!!)My concern is that I need to run a 39 pilot jet (for a OKO 28 carb)with the stock needle at it's leanest position (highest e clip position.) I hear a 55 pilot jet is ideal. If I run that the moped is very sluggish and "garggly..." I was told this is due to low compression. It runs fine as it is, but I wonder if I should keep on cutting the head to attain the 130-150 psi compression? Or should I just be happy how it is?? I would say the motor runs strong, but I am not too sure, because I am new to this world of mopeds.... Any advise would be greatly appreciated!!! Aloha. Bob.
Save gas and have fun doing it!!!
Posted on Jul 22, 2004, 9:30 PM from IP address 69.75.15.63
I would suggest leaving the compression where it is, Unless you want to go with the added exspence of water cooling your engine.
on khien carbs and other carbs the bigger the number the bigger the jet
if that is true with the OKO then the 55 would be richer than your presnt jet and you are running your present jet at it's leanest setting
why is that.. in most cases as the cc's increase the jet size increase enable to give the enigine the fuel it needs, to lean is too HOT !
I assume you are running premix and did away with using the oil injection pump or bought a bigger capicity pump.. if not your motor's on a quick path to death by seizing ( too hot not enough lube )
TheMopedWhiz
Ride Mopeds..SAve Gas..Have Fun
Posted on Jul 22, 2004, 11:06 PM from IP address 66.174.6.204
Yes, the larger number jet means richer. Right now my pilot jet is a 39 with the needle at it's lowest point and with that set up the bike takes off like a blast, but if I go to the 55 pilot jet, the bike is very "gargalish." I am using pre mix only (Motul 800 2T) with a ratio of 50:1. My head temp averages about 340- 360F at speeds about 30-45 Mph. But when I do an ocasional "blast" to about 65mph my temp climbs fast to 400F and that is when I lay off on the throttle. I may seriously consider using the water cooled cylinder kit in the future. Thanks for your time and knoledge Bobby.
Posted on Jul 23, 2004, 12:06 AM from IP address 69.75.15.63
I am selling my 1978 Honda Express. It has 1400+ miles and it did run after patching the cracked carb. It is in great shape, with a new battery. I can't ship it so it would have to be picked up. Pictures are available upon request.
Posted on Jul 20, 2004, 3:27 PM from IP address 64.90.76.174
It is in really great condition, with no scratches and all parts intact...I would sell it for $300.00. It has 1416 miles on it, a new battery, new air cleaner and carb kit. Can't be shipped...I can send pictures if you would like a better look. SMW
Posted on Jul 24, 2004, 3:26 PM from IP address 64.90.76.240
I forgot to mention I also have the Official Honda manual and Repair manuals. Pictures can be seen on ebay of the bike. Shipping quotes have varied from $148-$341. SMW
Posted on Jul 29, 2004, 10:13 AM from IP address 64.90.78.112
i need kick start gears for a 1982 honda urban express 50cc
by
(no login)
im looking for kick start gears or replacement engine that runs. is a electric start available on my model. im kind mad i just bought the bike and the kick start went to stripping do i need to oil the gears.
Posted on Jul 20, 2004, 2:16 PM from IP address 216.163.96.251
HI , got my 64cc metra kit and pipe for honda 78 nc50. The mechanic ran the throttle to full and the piston scored the cylinder wall. he blames it on air being sucked into the cylinder from the outside due to a grind job (which is apperently not level. I blamed it on the mechanic, since when do you run a new kit at full throttle without even doing a jetting job on the carburator!?!
now im stuck with a 200 dollar bill and no moped.
does anybody know anything about this so called siezing which can happen if there is an air leak.
I thought that compression would be lost and would be detected right?
JOnathan
Posted on Jul 19, 2004, 2:59 PM from IP address 69.157.154.104
Though I cant say anything for sure about an air leak, I can tell you a few things.
First of all, When breaking in a new piston/cylender/rings you NEVER wanna gun it. You must ride it gently for many miles to properly set everything.
Not to mention the express is AIR COOLED and therefor must be MOVING in order to be properly cooled.
What happens when metals get hot? They expand!
And what happens when three metal parts that are all pressed against each other that have yet to wear down to fit nicely suddenly expand at high speeds?
You guessed it. Seize!
Now as for that air leak. The Express is oil injected.
What this means is the same ammount of oil goes into the engine regardless of the gas to oil ratio.
When you run at idle, you get enough oil for idle. When you run at top speed, you get enough oil for top speed.
So correct me if I'm wrong, but that means that running too lean (from an air leak) would not actually cause damage.
If I took my bike in to have a new piston/cylender put in and THEY seized it and then charged ME, I sure as hell wouldnt stand for it.
You dont need to pay for their mistakes. Check any paperwork you may have signed when you brought it in. Most places have you sign something which limits their liability to a certain ammount. But that doesnt give them the right to go ruining customers equipment. Go have a word with them, or their manager if need be. And go informed. You shouldnt need to put up with this crap.
Posted on Jul 20, 2004, 2:01 AM from IP address 154.20.89.136
and that pump calibrated at the factory by honda injects exactly the right amount of oil, exactly the same amount of oil per revolution of the crankshaft
it doesn't make any difference how fast or how slow , it always the same little squirt ,, for each shot. CALIBRATED FOR A 49cc engine
NOT a 65-70cc engine
it has been stated many times in this forum..
if you go bigbore you MUST premix your fuel and mix at 25:1
that 1 gallon of gas and 5 ounces of good motorcycle oil , NOT weed wacker oil..
if you didn't premix your fuel before taking it to the mechanic,, you are also guilty of contributing to the seizing of your engine..
yes he was wrong to rev it up. it should have a 300 mile break-in period.
but you may have slipped up.. I don't know if you rtead everything and did
your premix or NOT
and for the other poster's (info)
the oil is part of the fuel ( it burns)
and air (vacuum )leak still means the fuel mix is TOO LEAN (to much air not enough fuel)
TheMopedWhiz
Ride Mopeds..SAve Gas..Have Fun
Posted on Jul 20, 2004, 10:46 PM from IP address 66.174.6.205
Need help! NC50 runs great but impossible to start
by
(no login)
My 78 Honda Express runs great once started(tops out at 25mph on the flats) but has always been impossible to start. Until recently it would never run and would blow tons of oil out the tail pipe. I had a Honda shop fix it (they charged more than the bike was worth)but said they only replaced some gaskets. Just replaced battery too. Some days it will start right away, other days it takes 10 minutes of cranking (during which I suffer humiliation while everyone at work offers me rides). During attempts to start it will sometimes start and idle, then slowly die off, or will kill as soon as you give it gas. I played with the needle valve to adjust the fuel but didn't make a difference. I still see tiny splatters of oil out the tailpipe. Are my rings bad? Is oil out the tailpipe normal? I've always thought there is too much oil mixing with the gas. The spark plug is fouled with oil most times I check. If I am leaking too much oil in the piston, should I disconnect the oil feeding the carburetor (since it already has plenty of oil in the piston from worn rings). I've tried this briefly and it seem the exhaust is still blue.
Any ideas?? Thanks!!
Posted on Jul 17, 2004, 7:30 PM from IP address 67.250.109.148
Thanks for the quick reply. I checked the gas from the fuel line and it was clean. I pulled the spark plug again to see if it was fouled and it looked surprisingly normal. That was after I had ridden for a while, so I guess I need to check it when I'm struggling to start it. The leaking oil pump is a good lead, but I'm pretty sure that is what the Honda shop replaced the seal on. Is this something I could dismantle to check and still get it back together, or would I need to replace the gasket again? Another thing I"ve wondered about is the oil cap. The old one was lost so I bought one a while back but it isn't tight in the hole. Would air leaking in the cap cause the oil to drain into the engine more? In other words, should the oil cap be air tight? Any other leads?
I appreciate your help.
Posted on Jul 21, 2004, 9:33 PM from IP address 67.250.109.37
If it's hard to start and runs only with the choke lever partly pulled, then it's probably the same problem I had with a friend's Express. I had to clean the carb and jet and all passages immaculately, and there's one passage that's toward the edge of the float bowl that is hard to find and gets overlooked. don-ohio
Posted on Jul 30, 2004, 5:26 AM from IP address 63.155.196.60
I amlooking for a carb. to fit a 1980 express.You wouldn't by chance still have one,would you? If so how much(resonably priced of course)? Thank you for your time.
Posted on Jul 22, 2004, 9:28 AM from IP address 209.240.205.68
Hi i would like to know if my 1978 express has any carburator which can be used that is not the original. One with changable Jets sizes since i put on my 64cc metra kit anf proma lowboy exhaust
Thanks
JOnathan
Posted on Jul 17, 2004, 6:47 AM from IP address 69.157.134.21
you could use a carb from the NU50, BUT you must also have the NU50 intake manifold ..
different carbs mount only to specfic manifolds..
but the mounting of the manifold to the engine crankcase is the same on all express models
the carb from a 1982 NU50 has removal jet but you will need that intake..
that carb use's an automatic choke ( which mounts on the right side of the cylinder ) so you will have to run without a choke blocking off the choke nipples..
www.50cc.nl has a perrformance carb kit, intake, carb , manual choke, airbox..
it will bolt to the express engine. BUT i do not know if there is frame and rear wheel clearance for it..
it is designed for the PA50 camino, like the exhaust and bore kit.. and faces directly to the rear wheel not sideways.. the PA has a bigger frame.
TheMopedWhiz
Ride Mopeds..SAve Gas..Have Fun
Posted on Jul 17, 2004, 9:55 PM from IP address 66.174.76.205
hard to start, runs a few seconds, then poofs like a backfire i guess. i just replaced the entire wireing harness, cdi, starter coil, spark plug etc.
seems to be getting a good spark, but very hard to start and gives a poof then dies.
Posted on Jul 16, 2004, 7:45 PM from IP address 67.160.30.178
i think ive narrowed it down to the spark being to weak, or worn rings? how bright and blue must it be? hmmm. ive rebuilt/replaced almost everything electrical minus the dead battery.
what should i do next?
Posted on Jul 19, 2004, 10:37 PM from IP address 67.160.30.178
I have a Honda Spree, mid 80's vintage.
My auto bi-starter on the carb is snapped off. The carb is a Keihn PA . The number on it is 29MAYKI. The bi-starter is the one with a fat brass needle. I have a carb from an 86 Spree and it has a different bi-starter. It has a small pointed needle. I need the one with the blunt end not tapped needle.
How much is one? Where do I get it?
Thanks
Dan
Posted on Jul 15, 2004, 7:58 PM from IP address 68.60.182.129
Would anyone on this list know what the differences are between the Honda Metropolitan II moped and the Honda Metropolitan to limit the speed? Does anyone know where a site that sells performance parts for these mopeds?
Posted on Jul 15, 2004, 4:47 PM from IP address 206.148.224.191
