Tubes to nowhere on Bottom of Carb Bowls?

bass-o-matic · Post by **bass-o-matic** » Fri Feb 29, 2008 10:19 am

I have a 64 CB77 with oval carbs... there is a tube coming out the bottom of each bowl going just behind the top engine cover... they like to dribble gas and about 2 or three CCs has collected on top of the engine!

Is this Honda's way of adding excitement to your ride? "And you could blow up at any time!" or is something wrong with my carbs? The do seem to leak around the bowl gasket but otherwise run and idle well.

very odd stuff.

dickinraleigh · Post by **dickinraleigh** » Fri Feb 29, 2008 10:37 am

Since I bought a 1967 Superhawk in 1968 I remember that there were hoses that went from the fitting and were routed down behind the engine and in front of the swingarm. I remember this because a friend had a 150 dream and he kept running out of gas at odd places. One float bowl at a time but we eventually got him enough gas to get to a station.
Dick in Raleigh
GL500s forever
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bass-o-matic · Post by **bass-o-matic** » Fri Feb 29, 2008 10:50 am

So, they are routed properly? Are they necessary?

LOUD MOUSE · Post by **LOUD MOUSE** » Fri Feb 29, 2008 12:48 pm

I'll reply here in an attempt to cover all 3 messages.
The brass tubes at the bottom of the CB/CL72/77 carbs are atmosphere vents not overflow tubes.
When these bikes were delivered HONDA didn't have tubes on them. (EVER)
Usually if tubes are there the engine CAN HAVE gas/fuel problems.
Granted if the float is bad or adjusted wrong gas will come out.
At times folks confuse the vent holes between the carbs as just going out to the area of the swing arm when in reality HONDA installed a plastic "Y" and ran the single tube to the right side air filter.
Don't confuse the CB72 bikes with the CB/CL77's because they (CB72) had a tube from each carb from the power jet to each air cleaner. .............lm

dickinraleigh wrote:Since I bought a 1967 Superhawk in 1968 I remember that there were hoses that went from the fitting and were routed down behind the engine and in front of the swingarm. I remember this because a friend had a 150 dream and he kept running out of gas at odd places. One float bowl at a time but we eventually got him enough gas to get to a station.
Dick in Raleigh
GL500s forever
<><

bass-o-matic · Post by **bass-o-matic** » Fri Feb 29, 2008 12:56 pm

Excellent. So just to be perfectly clear. In my case, I should:

1. Make sure the floats are adjusted properly. ( I have no idea what this means.)
2. Remove the tubes from the carb bowls.

Thanks

dickinraleigh · Post by **dickinraleigh** » Fri Feb 29, 2008 1:24 pm

Maybe so but my carbs had black hoses with the little wire clamp going to behind the engine. This I remember clearly.
Dick in Raleigh
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LOUD MOUSE · Post by **LOUD MOUSE** » Fri Feb 29, 2008 5:59 pm

So may I ask how many of the CB72/77 HONDAS you've had during your life and please give me an idea how many were NOS/OEM from the dealer and the year you bough it/them. I ask for this info because several years back there was a feller (HOYT) who though he knew all about this issue of HONDA (because he and his brother both bought a NOS/OEM bikes sometime in the early 60's) and made the same sort of statement and when he did I realized he had actually had a 250 HAWK with the power jet carbs. I see you are new to this forum and I welcome you and you may want to keep in mind that I've been involved with these issue HONDAS since 1963 and have a fairly good idea how HONDA issued them to the US market and I for sure know how the carbs were and how they work and why. Once again welcome. .........lm

dickinraleigh wrote:Maybe so but my carbs had black hoses with the little wire clamp going to behind the engine. This I remember clearly.
Dick in Raleigh
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