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K1 jet kit?

Cbguy

CB750 Member
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hey there, I have a 71' currently with drag headers and am thinking of getting a 4 to 2 to 1 exhaust. When I open the throttle while at highway speeds the bike sometimes bogs down a bit. I know it's probably an issue associated with rejetting the carbs. As I've heard most bikes come off the line on the lean side and once you change the exhaust it can affect performance even more. I'm wondering if anyone can suggest the size and type of jets that would work for my bike. I've had a hard time finding anything.
Thank you.
 
Drag pipes are terribly inefficient on stock motors and general riding conditions. When you are riding and you encounter the bog, slowly close the choke...if it gets worse it is already rich, if it starts to pick up while closing the choke it is lean. You can do this at different throttle openings...wide open for main jet, middle throttle is needle clip position. You will need to see what you have for jet size in there right now before you can select a size after you do the choke test. There is no set jets that work for every bike...exhaust, air filter setup, engine condition, tune up condition, altitude, fuel quality, riding habits all affect what a bike will need for jetting...no two bikes will react the same and you need to jet to what you bike wants. As far as jets, either order from honda or go to jetsrus.com they have idle and main jets, either oem or less expensive brand but I have found they work just fine for less money.
 
X2 on that, a simple cut off header pipe is the most wasteful exhaust there is, the tuning signal is too short and too strong, it commonly messes up carburetion unless you are an expert at doing it.

Like said, there is no one setup that will work there, it has to be worked out by trial and error, the straight pipes make it worse to me, that plus engine condition tend to argue with each other a lot. I've seen a way off correct length of straight pipe actually make an engine go richer as compared to the full OEM pipe and muffler setup, meaning the engine LOST power with the straight pipes.
 
Thank you for your response's. I haven't been on here for some time, I definitely want to get rid of the drag pipes. It sounds like anything will let the bike run better than drag pipes.
 
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