Will I need to tune/rejet carbs?

[rappz7]

I plan on using my stock headers with some after market slip on mufflers to finish them off. My stock mufflers were about 26 inches long. I found some reverse cone slip ons in both 26 inches in length and 17 inches. Will 9 inches be enough to have to re-jet the carbs or will they run similar to stock without touching the carbs? Anyone have experience with doing this to a 1979 cb650? All information and input is greatly appreciated.

 

[hillsy]

If you're running a stock intake (IE: air box) then just changing the mufflers will probably not need any jetting changes. You may want / need to adjust the idle circuit (because it's adjustable) but it shouldn't be by much, if any.

 

[Tune-A-Fish]

Classic DB rule.

If the pipes are loud as fuck after, you need to at least do chops. or if you are able, just ride it and see how it performs comparatively. Wear ear plugs if its "loud as fuck"

 

[rappz7]

If you're running a stock intake (IE: air box) then just changing the mufflers will probably not need any jetting changes. You may want / need to adjust the idle circuit (because it's adjustable) but it shouldn't be by much, if any.

Yes stock intake. The only thing im changing is the mufflers.