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Thinking about replacing stock carbs on my '77 with the Keihin CR set up from Cycle x

hje_326

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I'm trying to restore my bike to stock as much as possible but have had nothing but trouble when it comes to the carbs. At least, I think it is the carbs. I've been looking at the CR setup that Cycle X has and I have been wondering, is it worth it?

From what I have read is the '77 comes with Keihin CV carbs. I'm completely carb illiterate but would like to learn more so I can take better care of my bike. What are the main differences between these carbs and which one is easier to maintain.

Also, if I do end up switching to the CRs, would I use the original airbox or would I move onto pod filters, or could it be something else entirely?

Thanks!
 
Been thinking about the same issue. I have been struggling with what I thought was a carb issue but then discovered what may be a bad stator. I would check coils, ignition, and charging system first before spending that kind of cash.
 
I'm sure there is a charging system issue because my battery needs a charge every few weeks. But what has me and many other baffled is why 3 and 4 are not firing after taking the carbs apart and cleaning them with chem dip.
 
just because you cleaned them in carb cleaner doesn't absolutely mean you actually got all the passages open. Sometimes carb dip doesn't work...only way to clean 100% is ultrasonic cleaning. Spray some carb cleaner in 3 and 4 while it is running and see if the rpms pick up....if it does you aren't getting fuel. If no change then you need to start looking into mechanical issues or ignition.

No the 77 doesn't have CV carbs. They didn't use them till 79 when the DOHC motor came out.
 
I've been trying to find a way to spritz gas in there to see if it a fuel problem. I've heard a lot about the ultrasonic cleaning. Are there any units that don't cost 500$ +?
 
with it running just spray it into the back of the carb on the air cleaner side. If the cylinders are not getting fuel it will run off of the carb cleaner. You can use the smaller jewelry ultrasonic cleaners if you split the carb rack into individual carbs.
 
Im runing the CR Keihn carbs on mine and love them!! Only thing about them is they dont run that great at low rpm and you have to roll on the throttle or it will just fall on its face. i deff love them tho. Deffinetly go fast carbs. Cheers!

Sal
 
That is the issue with the CR carbs, the part throttle isn't as smooth as the Mikuni RS series carbs. The CR is a upper mid to top end carb.
 
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