trying to tune a cv
 

i have acv which has a surging problem in every gear when you just touch the throttle you can feel it jerking slighty it gets a bit annoying when you are in traffic. mid range is good and top end good.it is a little bit slower to respond when bike is hot.i reset points, new harley plugs and tryedwinding mixture screw in all the way when bike was hot and it made no difference to idle.does this mean something. screw is set 2.5 turns it has a #45jet and a#170main

RE: trying to tune a cv
 

Hi hddee,
tell us a little more about your set up, IE engine size, cam, pipes, year?
how was it running before you installed the CV?
what carburetor were you using before the change if you just change the carburetor ?

If your not getting any response with the air fuel mixture adjustment you may need to re-jet the intermediate jet {this is the what to do with an S & S}.
First check to see that the mixture screw passage is clear and not plugged.
check that there are no vacuum leaks.
Timing set with more advance that needed?
keep us posted on what you find.

RE: trying to tune a cv
 

i have a 79 flh80cube stroked with 4 1/2" flywheels, b grind cam, taper turbo pipes, points set at 18 thou and cv is fitted with thunder slide kit and a #45slow speed jet

RE: trying to tune a cv
 

don't know much about the CV?
is this a new carburetor for your bike and has ran good in the past before installation or something that has just started to happen recently and the engine was running good before?
did you make any other changes {IF}while installing the CV on your stroker engine?
Sorry for all the little questions but for us to get out brains wrapped around whats going on I need to know as much about the conditions as possible. :eek:

RE: trying to tune a cv
 

Your problem is the thunderslide kit. keep everything that came with the kit, except the slide itself. change that back to the stock. the thunderslide is too light, and rising to quickly with light throttle, causing your surging.

RE: trying to tune a cv
 

If you can run the idle mixture screw all the way in and the bike doesn't stall then something is up in the idle circuit. Someone may have run the adjustment screw in hard and messed up the seat in the carb body for the needle end of the screw or both the screw and the seat and it is now bypassing the adjustment screw allowing fuel through the idle circuit.
Try jmetro's fix first to see if that fixes both problems (idle and surging). Maybe the light slide is riding up at idle and letting fuel for idling get into the engine...I have never used a thunder slide so this is a wild guess.