New Carb for my Urban Express

I need to get a bigger carburetor for my Urban Express. Anyone know what will work with it since it has an auto choke..?

Re: New Carb for my Urban Express

If you intend on keeping that auto choke system then you are severely limited ! I would suggest you consider discontinuing its use and using a carb with a choke system built in as most already do . Cable or pull choke = easy + avaliblity . most likely you dont even need a bigger carb yet if your still mostly stock . First get pipe and upjet and air filter and upjet , then other mods like variator weights . And so on and so on . The stock carb has some adjustments even with the stock jet , you can move the needle a bit . This carb is good for an easy 40mph reliably . Keep it until you get a kit . Sorry for the long post . My two cents , for what its worth .

Re: New Carb for my Urban Express

Already got a new performance exhaust, new air filter.. still need to upjet.. put a new belt on and its going over 40 already and its running really lean so i raised the needle a notch.. i'd like to just go ahead and put a bigger carb on instead of relying just on a bigger jet..

Not sure how i'm going to get rid of the autochoke system... maybe get a new head?

Re: New Carb for my Urban Express

raising the needle makes it leaner, move it down. you can take the autochoke off the head, just a few bolts, but you need to plug the hole on the intake. heres the manual if you need more info.

http://www.mopedriders.org/html/manuals/honda/uexpress/huexpresssm.htm

whats your setup right now? mine is all stock except for proma circuit & bigger jet. runs great, except it sucks water into the float bowl when it rains. just pushed it home in the rain, fun fun. time to check for leaks...

Re: New Carb for my Urban Express

i mean the clip on the needle, duh. nevermind.

Re: New Carb for my Urban Express

i have the same exhaust. it rules. most everything else is stock as far as mechanically goes. you sure you can just take off the auto choke and plug it like it ain't no thang..?? that's awesome if so cause i'd really like a better more tunable carb.

but yeah. change your belt. you'll be stoked.

Re: New Carb for my Urban Express

if you get another carb you dont need the autochoke mess of hoses, youd need to plug the extra hole on the intake, unless youre gonna use a different one.

Re: New Carb for my Urban Express

So anyone know what carb will fit? or rather what intake??

Re: New Carb for my Urban Express

well IRE Rick was making intake adaptors a while ago, ask him. maybe a hobbit intake would fit, since they can use the same reeds, but im just guessing. got any hobbit friends? i wouldnt mind ditching the autochoke and adding a manual one to keep the carb, since i finally found jets to fit, but with all those extra hoses, i'm not sure how.

Re: New Carb for my Urban Express

Just get a set of vacuum plugs from the auto part store and plug them all up. It will run fine, but you won't have a choke though which can suck in cold weather.

Any recommendations on where to get a new Urban belt besides a Honda dealer? Anyone found a Kevlar that fits?

Re: New Carb for my Urban Express

well, i ride year round, unless its snowy (or rainy lately). this is my daily driver, get to work commuter, anything i could rig to hook up to one of those hose inlets?

as for belts, i dont know. are all the dealers out? maybe if enough people bug Treats, they can find something. or maybe overseas, it is called the Runaway over there.

Re: New Carb for my Urban Express

I believe that the auto choke use an thermo-operated (bi-metal) reed type valve to change the port from cold to hot. I'm not sure if there's a way to be able to trick it, at least I've never considered it.

I suppose you could put a small manual valve between the appropriate two vacuum lines and do it manually. Maybe use a small valve like a drain cock from Home Depot. Close it to start and then open it to run. Carb don't know if it's hot or cold, only the head temp.

I can order the belt through the Honda dealer only it cost about $30! I found a really close one at the auto store for $11, but waited.

Re: New Carb for my Urban Express

well because of the movable drive and driven faces it really doesn't matter what size belt you put in it as long as it's close to the same length. i bought one from advance auto parts and it works fucking awesome. just bring your old belt up there and try to match it with some they have. you'll probably want it a few millimeters thicker though.

there's some cool shit you can do with it if you experiment with different lengths and thicknesses of the belts due to the variator weights

I figure since the auto choke is basically just a thermostat then it won't matter if you just plug it up if you plan on getting a new carb with it's on choke. right? maybe?

Re: New Carb for my Urban Express

I used a 16vm mikuni knock off for a while on a regular nc50 express. It has a cable choke and it uses the same mounting, i.e. the two bolt flange deal. Had to open the holes on the carb a litte, or on the intake, but only like 2 mils out, easy file or dremel work. Right no I am running my kitted express on a 19 phbg knock off I got from this dude

http://shop.hkmotos.com/product_info.php/products_id/69?osCsid=19adf54b06ce68b9a92f6e2b8edb90cc

I used the rubber intake mount thing that came with it and drilled 2 new holes in it to match the holes on the express intake. It works well for me, and the urban and regular express have the same intakes, but 19mm but be a little much on a stock bike. I guess if you didn't open up your intake at all, you would only be getting like 16mm worth of mixture, so that might be ok. Cheap experiment for sure though. It has a pull choke, so thats a non issue. Everything you need is in that package deal, except you are going to have to trim down your throttle cable housing maybe 2" or so.

Re: New Carb for my Urban Express

While waiting for 16.16 carb, I have some questions.

I did the Polini circuit exhaust, and lowered the clip on the metering needle to the lowest position. Do you think this is rich enough?

How do you guys look for correct mixture.

The exhaust really helped the top end and now need to work on below 20MPH acceleration. It really made the bike more ride-able.

With Deloroto (sp) how do you manage throttle cable. My plan is manual choke and eventually oil/fuel mix

Thx for any response.

Re: New Carb for my Urban Express

Search plug chop. Its pretty much checking what color your spark plug electrode is.

Re: New Carb for my Urban Express

Take three weights out of your variator and your 0-20mph should improve dramatically.

Just make sure the remaining weights are spaced evenly so that your variator is balanced.

You can use your stock throttle cable. Just take a file and grind the knarp down till it fits your carb slide. I am assuming you went with a dellorto 16.16.

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