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Author Topic: Carbs on a 78  (Read 14043 times)

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Offline BobbyR

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Re: Carbs on a 78
« Reply #25 on: August 14, 2008, 07:10:39 PM »
Soak everything in Simple Green for a few hours and get some strands of copper wire from an old lamp cord. Take one carb apart at a time and you have the others as a guide.
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Offline rbmgf7

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Re: Carbs on a 78
« Reply #26 on: August 14, 2008, 10:22:09 PM »
be careful not to leave then in the simple green for too long or it'll begin to accumulate some kinda white residue that can gunk up the orifices. did it to my keihins and it was a blast to clean that mess up. follow bobby's instructions and you're good to go.

hope no one is talking smack about the PD carbs. gosh, somehow i managed to gain 4 sets thinking it would be better to use these instead of the older K keihins. figure the accel. pump was a plus to have.
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eldar

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Re: Carbs on a 78
« Reply #27 on: August 20, 2008, 08:47:08 AM »
The later carbs are awesome. Much better for tuning, especially with the 77 needles, than the older carbs.
They are also much more flexible. People have run pods with them and have only had to tune the idle mix screw. Cant usually do that with the early carbs.

As for simpler, in what way? Only real additional part is the accel pump. And that is easy to work with.
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Offline dchautin

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Re: Carbs on a 78
« Reply #28 on: January 29, 2014, 07:01:58 PM »
Can someone send me a link to the 78 carbs manual?  I'm desperately trying to get mine in working order.  Leaks at the alum fuel tubes between carbs.  Thanks


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Offline lucky

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Re: Carbs on a 78
« Reply #29 on: March 13, 2014, 06:55:34 PM »
I put the 1969 carbs on my 1978.
A lot more power and much easier to work on.
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Offline dchautin

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Re: Carbs on a 78
« Reply #30 on: March 13, 2014, 07:00:24 PM »
Really?  Was it hard?  Need different carb boots?


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Offline dchautin

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Re: Carbs on a 78
« Reply #31 on: March 13, 2014, 07:01:28 PM »
Got them to stop leaking but now won't idle without the choke on. I guess they need to be synced.


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Offline TwoTired

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Re: Carbs on a 78
« Reply #32 on: March 13, 2014, 07:45:03 PM »
Either vacuum sync, or maybe some pilot jets are clogged. 
Checked for even head pipe heat?

By the way, the PD carbs have the very same venturi size as earlier carbs, so they make exactly the same power for those who are able to tune them.  They do have some extra complexity that is beyond some individual's ability to comprehend.
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Offline dchautin

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Re: Carbs on a 78
« Reply #33 on: March 13, 2014, 08:06:00 PM »
Any advice or link to how to sync? Thanks guys


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Offline TwoTired

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Re: Carbs on a 78
« Reply #34 on: March 13, 2014, 11:19:59 PM »
Get a vacuum gauge set.  Adjust 1,3,&4 to whatever #2 shows for vacuum.

The Honda shop manual is a pretty reliable reference.
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Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Crack On

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Re: Carbs on a 78
« Reply #35 on: September 14, 2016, 02:55:44 PM »
Link appears to be invalid as of 9/14/16
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