Author Topic: Cracking hoses. Take a peek. What to do? 78 750f SS carbs  (Read 898 times)

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Offline apetersonboy

  • 1978 CB 750F SS
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Cracking hoses. Take a peek. What to do? 78 750f SS carbs
« on: September 25, 2012, 07:29:05 PM »
I'm debating whether or not I need to get these little hoses replaced... Not even sure what purpose they serve. Cracked at both ends on all four of them. They connect all four carbs. What do they do? Should I have them replaced? Thanks!






IF they do need replaced, would it be too much of a job for a lightly experienced mechanic (me)? Or should I take it to a pro?
Again, thanks for any help. Carbs are a foreign object to me, and I'm quite lost. Thanks

Offline brewsky

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Re: Cracking hoses. Take a peek. What to do? 78 750f SS carbs
« Reply #1 on: September 25, 2012, 07:46:25 PM »
They connect the carb bowl vents to a single hose..

You can cut them in half, pull off and replace with a short piece of fuel line.
66 CA77
78 550K
78 CB750K
02 FZ1
09 GL 1800

Offline apetersonboy

  • 1978 CB 750F SS
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Re: Cracking hoses. Take a peek. What to do? 78 750f SS carbs
« Reply #2 on: September 25, 2012, 08:09:48 PM »
Without taking the carbs apart? Awesome. This'll be a lot easier than I though. Thanks!

Offline brewsky

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Re: Cracking hoses. Take a peek. What to do? 78 750f SS carbs
« Reply #3 on: September 26, 2012, 07:53:11 AM »
No need to break the carbs.

About any kind of hose would work there, as it is just a vent.

Breaking the carb bank is a pain.
66 CA77
78 550K
78 CB750K
02 FZ1
09 GL 1800

bollingball

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Re: Cracking hoses. Take a peek. What to do? 78 750f SS carbs
« Reply #4 on: September 26, 2012, 08:04:26 AM »
+1 vent lines If the bike is running good and does not need carb cleaning let it rip. Not so easy to do with them on the bike. But it can be done.
Ken

Offline flybox1

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Re: Cracking hoses. Take a peek. What to do? 78 750f SS carbs
« Reply #5 on: September 26, 2012, 08:18:39 AM »
Be careful on the lower front ones, with the end clamps. they should have brass restrictors inside the tubes.  if you do replace them, dont loose these brass tubes.  take them out and put them in your replacement sections.
they provide increased pressure in the accel pump circuit and a better squirt into your carbs.

There are 2 parts to your carbs that are crucial to your bikes proper starting and running.  ensure they are  functioning properly.
1. accel pump circuit attached to carb #2.   
2. fast idle cam.   
refer to your shop manual for details or search here on the forum.  they have been covered in depth.
« Last Edit: September 26, 2012, 08:30:50 AM by flybox1 »
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
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Offline apetersonboy

  • 1978 CB 750F SS
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Re: Cracking hoses. Take a peek. What to do? 78 750f SS carbs
« Reply #6 on: September 26, 2012, 02:30:15 PM »
Thanks for the info guys, ya'll rock. Gonna go tinker a bit now