1979 Z50 - can not remove main jet from carb, having trouble tuning after rebuild

[surrealism]

Hey Guys,
New to the site, and have really enjoyed the 2 weeks of reading all the useful info. Today I decided to post a question I cant seem to find an answer to.

just bought a 1979 Z50, and was told it needs a carb cleaning. so I soak it and run wire through every port (the smaller jet seems to be jammed up and I cant see light through it - red arrow- ).

It appears to me the main let (the bigger hole) does not have a threaded insert. On all of my research I see carbs that you can remove the brass jet and a brass sleeve to better clean out the venturi. Am I crazy, or is this model not adjustable?

 

[theraymondguy]

the remaining thing thats in the carb is the emulsion tube - yes, its pressed in and non serviceable. Time to break out the chemicals: jewel cleaner, pinesol, carb cleaner.

Most likely tuning symptoms are: won't run without choke, stumbles down low.

 

[ParakeetZ]

I am having the same problem with a 76 model. I can stick a wire or micro drill bit up the brass part but can't actually go all the way through. I have tried wire which collapses because it's too fine, drill bits aren't long enough, carb cleaner, brake cleaner, air pressure, water pressure and still no luck. Even boiling the carb didn't help. However, some of this may help you. Good luck!

 

[Mr.Horsepower]

I've always had good luck pulling a strand of wire out of a good quality wire brush, insert it into the pilot jet or slow jet hole and with a good pair of needle nose grab the wire not flush but a little above the hole and keep feeding it in little by little, it will go all the way through and then your all set.

 

[darrel gunderson]

I often times use Ez off oven cleaner on carbs but, Not too long or will turn the surface black!

 

[b52bombardier1]

I will boil the troublesome carbs in CLR bathroom cleanser to get the white oxide out of the deep places. Do this outside because of the smell. And do not boil the throttle slide because the anodizing will be removed by the CLR. This is an admitedly harsh technique that is controversial to some.

The carb body parts and the brass respond well to the CLR though.

Rick

 

[surrealism]

Thanks guy, It looks like I might just need to go get a a new carb that ill adjust for more service options in the future. Any tips on a decent replacement, are the China versions any good?

 

[b52bombardier1]

I cannot speak for the 50 cc bikes but there are minor fitment issues with the 90 cc bikes.

Rick

Two Honda ST90 and Two CT90 Bikes
2006 Honda Foreman 500 (Resto In Progress)

 

[Ufester]

I like to use elcteric guitar strings to snake through my carbs. I use the metal E B G strings depending on diameter I need. They are stiff enough and long enough and made of stainless steel.