How to Clean Motorcycle Carburetors





Introduction: How to Clean Motorcycle Carburetors

This free motorcycle was sitting in David Durlach's garage for 20 years.

David eventually tired of it, and gave it to Prank, who cleaned out the brake lines and added a new battery. Then winter happened, and it sat in Deepest Darkest Somerville for a year, until prank graduated and moved to California, and I was given care of the motorcycle. I wheeled it back to MITERS to see if I could get it to work. A new battery, some carb cleaner, and a little bit of hope, and it started up! Yum, throaty rumble!

With visions of a cross-Cambridge joyride followed by summers of long-distance road trips, we took it to the road and kicked it into gear.

But, every time the gas was added from the gas tank, the 'cycle coughed up and died. Oh well.

I emailed the MIT Motorcycle and they said "clean the carbs". With a monkey wrench and a vague idea of what I was looking for, I did all of the following. Now they sparkle!

Step 1: Get the Float Bowl

There are some haaard to reach screws in there, man.

Get them all out, until the float bowl is in your hands.

Step 2: Scrub

I noticed all this brown gunk in the bottom of the float bowl. How to get it out?

I grabbed a tuft of some really fine steel wool, and used a cheap pen to rub it into the areas to small for my fingers.

When it looked shiny, I sprayed in some carburetor cleaner I picked up at the gas station across the street.

Step 3: That's It!

Screw the float bowl back on, and you're done!

Vroom vroom, enjoy!



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    The easiest and most thorough way to clean a motorbike carburettor is by using an ultrasonic cleaner. More info:

    Ultrasonic cleaner with a bank of 4 motorbike carburettors.jpgmotorcycle carb cleaning.jpg

    So how are you going to go about registering with the DMV? Do you have the title from whoever gave you the bike?

    No title for it a-tall. I'm not sure yet - I thought maybe I'd jump that ramp when I can drive up to it.

    Alot of southern and western states are a little looser on the title part. See if you can find out who the last registered owner was, then apply for "lost title" in their name. In some states you can get salvage, builders, or bonded titles. If you have friends or family in one of those states, it won't be too hard. Good luck. I've owned a GS bikes. Change the oil regularly, turn the fuel "off" when parked, and it should last forever.

    i have a 1978 gs750 and my fuel swithc say's " pri, on, res" which one should i set it to in storage...?

    I had the same question. The dealer I bought it from said leave it on prime and run it til it dies. That should leave the carbs pretty empty over winter.

    You should have two inlets on the petcock one goes to carbs for fuel flow other hooks to vacum source to open petcock set to on to store turn to pri to start and then set to run ands let i run down the road with no vacum at petcock fuel will not flow Yam, Kaw, and Suz all use thois set up on biogger bikes

    That must be why its so heed to start on "on" and easier on "pri" thanks

    turn the fuel off and run the engine out of gas - no varnish build up!

    no fuel off... i guess with my model the air box was converted to pod filter (which is another mess in itself) but the air box had a vacuum to prevent the gas from leaking.... i have to figure out how to put the airbox back on now..... tried once this summer, but couldn't get it to fit with a 1/2 full tank on... hopefully i can drain it this weekend and then try this winter to put the airbox back on.

    the person before me (a friend) took the airbox off for more power, but never rejetted just played around with the carbs for a 'better' air flow... i beleive putting the airbox back on will fix a ton of stuff.... or a re-jet.

    thank you all