One of the first things I always do with a vintage bike is go through the carburetors. Rebuild gasket sets are inexpensive and freshly rebuilt carbs help to eleminate problems you may encounter with a new bike. New as in "new to me", where I don't have any previous experience with the bike.

In the case of this SL175, I was told it was ready to ride and had been gone through. A short 3 mile ride to my local Post Office and back proved otherwise. When I pulled the plugs they were dark and sooty. It looked like the bike was running rich, so off came the carbs.

A Quick Visual Inspection:

On a positive note, the jets, the slides, and the needles were all original Keihin. The carbs also were fairly clean without any sticky varnish or dirt in the bowls.

Obvious problems included, the float height was not set properly, the fuel inlet nipple on the #2 carb was not seated well into te carb, where Honda used o-rings to seal the carbs to the manifold and the mainfold to the head someone had added paper gaskets covered with what appeared to be anti-seize compound over the old hard o-rings. The cable adjustments at the top of the carbs were also screwed out as far as possible.

After a complete disassembly of the carbs, I ordered up a couple of complete carb gasket sets and sent the bits and pieces off for some time in the ultra sonic cleaner.

A Good Clean in the Ultra Sonic:

It's bee about 10 years since I purchased my ultra sonic cleaner. I don't know how I got along without one! I've heard guys say they weren't impressed with the results, but that's NOT been my experience! I think my Velvor 30 litre modle works like magic. I use the purple simple green HD cleaner as it doesn't react with aluminum.

I fill the unit with water and then put my carbs into their own smaller containers with cleaning solution. I add just enought simple green HD to turn the water a purple tint. In the photo above, I'm using plastic a ice cream container for each carburetor. I like to keep the parts with the carb body that they came from so when I'm done the carbs are reassembled with the parts that came out of them.

Everything cleanedup extremely well and the original brass bits were nice an shiny. After drying, I spray carb cleaner through all the brass and ports in the carb body. You can't have carbs that are too clean. Do it right the first time, or you will be doing it over...

Ride safe & take care - Dennis