Hi everyone,  Can someone tell me where you measure from, on the carb body to set float height on a RT 1 carb. All the books say 14 mm from were the jet setter screws into ???. Is it not from the face on the body where the float bowl fits. Thanks in advance. Alan.

Float arms should be parallel or very nearly parallel to bowl gasket surface. 

And yes, Yamaha used the jet setter measurement on some early models.  Float level specs might also be the spec that is most often incorrect in the manuals...  sometimes the same manual has different specs in different parts of the manual!  So see above.  Parallel is simple and is where you end up following the correct spec on every one I've ever done.

Thanks Markt, Will set it up and give it a try. Cannot understand why they put the wrong information in the books. Thanks again.

The information in your book might not be wrong.  It just can be.  There are a lot of errors in that era of Yamaha manuals.  Seems to be worst in the mid-70's.

You can follow the manual instructions.  If you follow the instructions and the float arms are not parallel or very nearly parallel to the gasket surface when done, either you've done something wrong or the spec is wrong.

I've seen bikes that won't run because floats are set at some wacky steep angle no where near parallel because "that's what the book said".  You'd think that anything more than a minor change in level would be a red flag... it apparently isn't. 

If a spec doesn't seem right, it probably isn't.

Have set lever parallel for float ,I don’t think you could have set it to the book. They said 14.1mm. So parallel it is. One other question is what do folks do for a air filter for anRT1.I made a cage from 3mm welding rod with modern motorcycle cross filter, just wondering if it over the top breathing wise.