'77 Hondamatic Project

[pmprogrammer]

Picked up a new project this past Monday. '77 CB750A Hondamatic with under 17k miles - garage kept, but coated with a very grungy-sticky dust. Last tagged 2006, last cranked 2008. But I think it's gonna clean up real nice.

 

[pmprogrammer]

Progress report: We have spark.

Spark Video!

 

[pmprogrammer]

Delicate 49 year old parts! Lesson learned.

 

[pmprogrammer]

Help with Tire Codes. So there's supposed to be different code styles for before 2000 and after 2000 according to the website: Decoding TIre Codes .

This bike was last registered in 2006, and last cranked in 2008. The tires have deep tread so were not ridden on much after these tires were mounted. Looks like a 3 digit tire code is used on the tires on this bike, but those were supposed to be used prior to 2000. So. Maybe these tires were manufactured in 1994 and 1995? And if so, it was not ridden much in the years leading up to that last registration in 2006. Pics below. Regardless, new tires are in order, once I make sure this puppy runs.

 

[pmprogrammer]

Yeah - got some work to do here.

 

[pmprogrammer]

Slide won't slide. (video)

Any ideas why the slide in this Keihin carb will not pull out of the carb body?

 

[pmprogrammer]

Slide won't slide. (video)

Any ideas why the slide in this Keihin carb will not pull out of the carb body?View attachment 21733

Turns out the needles (all 4 carbs) were varnish-glued into the jets. Berryman's Chem-Dip to the rescue.

 

[Old_Crow]

Turns out the needles (all 4 carbs) were varnish-glued into the jets. Berryman's Chem-Dip to the rescue.

Old school...I like it. I wonder if you could use that stuff in one of those ultrasonic cleaners without causing an explosion or some other health hazard.

 

[pmprogrammer]

Old school...I like it. I wonder if you could use that stuff in one of those ultrasonic cleaners without causing an explosion or some other health hazard.

Prolly not a good idea.

 

[Old_Crow]

Prolly not a good idea.

Ah, hell...who wants to live forever anyway?

 

[pmprogrammer]

Please let us know how it all works out for ya!

 

[Old_Crow]

Please let us know how it all works out for ya!

It was just musing. I live and travel in a motor home. I pull my 750 and a Jeep behind me on a trailer. No shop anymore, so no place to keep an ultrasonic cleaner. Guess I dodged a bullet.

 

[pmprogrammer]

So. Been in the carbs a lot. Got 'em cleaned up but been chasing the leaky float gremlin. Decided to temporarily install them to at least see if the bike WILL run. I got it in Feb '26 and it hadn't been cranked since 2008. At least now I know if I get the leaky floats fixed- IT WILL RUN!

Video - 1st Crank 2026-05-10