Magnum II- CARB

I was wondering if you can help me a little. I am getting tired of randomly

buying carbs on E-bay w/ no results, and I hate to get rid of the ped for a carb issue.

I have a 1980 Magnum II but cant tell from any numbers what model it may be. I do know it has two speeds.

The original carb was thrown out by someone so I have been left w/ no info.

The two carbs I have 1/12/293 and 1/14/160 dont seem to give me the power I think the moped should have.

I see that there are slots in the jet needle. Should it be set in a specific slot?

How do I know what the correct jet is or should be? Etc.Etc.Etc.

Any suggestions would be a great help.

Tom

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Re: Magnum II- CARB

This should pinpoint your stock carb. It seems it's a 12 mm. The 12mm you now have should be fine. You may want to install a different main jet depending on the results of a top speed plug chop.

http://www.mopedarmy.com/resources/articles/bingcarbs/

Here's a Puch service manual for several '80-'81 models.. you might find some useful info there.

http://www.mopedriders.org/html/manuals/puch/sm/puchsm.htm

Stock mopeds don't have much power.. expect to struggle up a hill.. 2-speeds have a tendancy to shift at exactly the wrong time and you might have to resort to pedaling. Playing with clutch weights can alter shifting characteristics somewhat.

Needles are normally on the middle groove or the one above it and then adjusted if the bike runs poorly near mid throttle.

Re: Magnum II- CARB

Thomas Carson /

Thanks Joe,

Any idea what the spacific numbers on the chart represent?

Do you think if I added a different exhaust it may give it more power?

Where do you recommend I purchase a different jet?

Thanks Tom

Re: Magnum II- CARB

i searched around.. went to Bing's webpage for the meaning of the numbers.. no luck.. but i'm sure someone here knows how to decipher them..

My guess is something like 1/12/293 means (1) barrel, (12) venturi in millimeters and (293) a style number? .. perhaps just a stock number that can trace all the carb's details through some Bing document.

Bike manufacturers know that restricting the exhaust is an easy way to make the bike quiet while restricting speed and power output.. necessary things when they want to legally classify their bike as a "moped"..

A tuned expansion chamber (exhaust) is going to provide the greatest performance improvement of any single thing you can just bolt on to a stock bike.. Top speed will probably rise by 5 to 8 mph.

After the exhaust is upgraded the ports could be messed with if you know what you're doing.. then perhaps a bigger carb. The alternative to porting is a larger cylinder/piston.. These "kits" often include a new carb and are instant bolt-on power.

Be aware that a modified bike will be loud and put just about all parts under increased stress that most weren't designed for.. like brakes and clutches. Maintainance and tuning become more important and more difficult.

Don't take anyone's advice about your jetting needs beyond getting an estimate. Bikes and riding terrain and habits are unique. Plug chops are simple to do. Familiarize yourself with your engine's temperment.

Search the forum (search link above) for places to find Bing jets for mopeds.. http://www.mopedwarehouse.com might be the place but i'm not sure.

Re: Magnum II- CARB

the numbers refer to what models had what size carb and jet requirement, the 12 and the 14 refer to the size of the carb, in mm,

http://www.mopedarmy.com/resources/articles/bingcarbs/

i wouldnt worry about what was originally on the bike, but i would suggest putting the 14 on and getting a bunch of jets and run trough a range untill the bike starts to sound and feel right, then do some plug chops to really get it tuned right, bing jets can be found at mopedwarehouse.com

there could also be some restrictions with gaskets in the cylinder, a glance at the puch manual shows what bikes had many gaskets in the cylinder, some can have up to four or five and they can pretty much be removed for added compression, just make sure theres no knocking sound or anything from having the piston hit the plug,

judging from the picture in your profile, if thats the bike your talkoing about, its a 2 speed engine with a hi torque cylinder, i believe in the manual the hi torque cylinders can be run without gaskets

i am only using a base gasket on my cylinder set up

you probably have a magnum pipe on there which is fine, but some of the lower hp puchs had a little restricter thing in the pipe which can be drilled out to raise it up to a 2 hp bike, so if thats the case you may want to do that,

theres a few other things you could do for some added hp and torque, things with the air flow and so forth,

but other than that the next thing is to start cutting/porting or buying performance parts, such as a pipe or performace air filter, or cylinder kits, or sprockets

Re: Magnum II- CARB

Puchs came stock with 14mm and 12mm bings, so you'll be fine with the 14mm, even if it came with a 12mm. The 14mm will give you slightly more power, but you won't notice it much until you add a performance pipe and or cylinder. What kind of speed are you looking to get out of the bike? Take some pictures of your cylinder, specifically the intake port, and post them here.

Re: Magnum II- CARB

That is a real nice bike,PMed.....

Re: Magnum II- CARB

Dirty30 Dillon /

This is the most ridiculous bump ever

Re: Magnum II- CARB

Probably Fred /

Your bike came with a 12mm bing, 212A atomizer and 60 jet.

I wonder if your bike still looks like that or if it's made into a almost cafe racer

and all murdered out

Re: Magnum II- CARB

There are so many many bikes with upside-down-backwards handlebars chopped up seats,too low to pedal, no front fender,sawed off rear fender Maxi's and Magnums wanna-be cafe racer molested mopeds that are not worth buying anymore...

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