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Cv carb

jel123

Active Member
I tricked out my friends cv carb on his 97 dyna and let me tell you it realley worked out well i highley recommend doing this it works,jel
 
Sure put in a 165 main jet 45 primary drilled out the slide to a 1/8 hole and changed out the needle jet and belive me the trottle response is a lot quicker,jel
 
The throttle response will improve with what you did but you may find in cold temps after drilling the slide that if you open the throttle a bit to aggressively at a lower speed that the bike will bog down because it's opening too fast.

The hi jet could be upped a bit too about a 170/175.

Use this as a test for that.


Quick and easy way of testing the main jet size.

Run the bike through the gears into third gear and run third up to 60-70 MPH full throttle, then chop the throttle about 1/8 to 1/4 back and see if the bike either surges ahead or stumbles then recovers.

If it surges ahead, your jetting is lean
If it stumbles and recovers , your jetting is rich
If it makes no difference, you're pretty close.
 
...drilled out the slide to a 1/8 hole

WOW! The last website I was thrown out of was disputing the owner/moderator or whoever it was, they were promoting their jet kit. The argument said that this was a trick done 20 yrs. ago and it didn't work.

I argued that it was a simple air rise of the slide was sooner because the hole was bigger. I then reinforced my argument by saying that changing to a more flowing air cleaner pleat would cause the engine to run a faster event and nothing has changed but the speed of the air thru the 1/8" slight difference as is the slight difference in the air cleaner pleat.

Banned: Reason is argumentative? No, I think I was discussing basic physics and fundamental flow. He wanted me to more or less not bring up the obvious so his product would sit on the shelf is a front to push his kit.

You could get away with a slower throttle twist or set a slight weight to it. He said it would defeat the 1/8" hole. My weight is a dab of glue [which I did not mention], but would want to know if that air change can be tuned buy weight or his kit?

Remember, we changed the speed of the rise. Not some jet needing a change. You just need a slight bump and that glue can be cut down to stop the ragged edge of the slide wanting to rise at the slightest touch of the cable.

Not my problem they cannot tune with glue balls not about to be eaten by the engine if it is sitting on top of the slide. Ha-Ha-Ha is get a lane. Tell me how to tune a CV. Wanna see my CV?
:newsmile063:
 
Although Ive not too many years on hd bikes to be really knowledgeable one thing i have noticed on air flow is the air inlet to the air box on a stock setup is very restrictive
and have on a few occasions drilled 1/2" holes in the plastic to allow greater airflow into the air box this does really help
then look at the shape and weave of the filter
not worth changing the filter if the air ain't there in the first place

Brian
 
Not worth drilling the air box if the filter is the restriction either.:s

The taller filter in the stage 1 is where you pick up increased intake air.

HD stock - 171 CFM
Stage 1 Big Sucker = 200 CFM
Stage 2 Big Sucker = 250 CFM.
Kuryakyn Twin Velocity = 270 CFM
K&N E-3014 = 248 CFM RK=3009 kit
K&N E-3037 = 301 CFM RK=3910 kit
HD-0800 = 231 CFM SE replacement
Doherty Powerpacc = 287 CFM
SE Air Cleaner = 287 CFM
Zippers = 321 CFM
Woods Carbs = 4 models 135 CFM up to 340 CFM
Wimmer V02 flows 255 CFM
BC Gerolmay Overflow = 800+ CFM
 
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Start at the beginning and work to the end
increase the air into the air box stock filter ain't that restrictive
but high flow filter on an UN modified air box wont get you anywhere as most of the restriction is in the design of the air box inlet

Brian
 
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