trying to tune a cv

Harley Davidson Forum

Sponsors

Harley Davidson History

trying to tune a cv

Printable Version

Harley Davidson >> Harley Davidson Motorcycles >> Classic >> Shovelhead >> trying to tune a cv

Page: [1]

Message

<< Older Topic Newer Topic >>

trying to tune a cv - 5/15/2008 2:09:03 AM

hddee

Posts: 5
Joined: 4/12/2008
Status: offline

i have a cv 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 tryed winding 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

Post #: 1

RE: trying to tune a cv - 5/15/2008 6:32:22 AM

Rodney

Posts: 688
Joined: 5/23/2007
From: Central Oregon
Status: offline

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.

_____________________________

1968 FLH owned for 30 years
2002 FXSTDI

(in reply to hddee)

Post #: 2

RE: trying to tune a cv - 5/16/2008 1:09:42 AM

hddee

Posts: 5
Joined: 4/12/2008
Status: offline

i have a 79 flh 80cube 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

(in reply to Rodney)

Post #: 3

RE: trying to tune a cv - 5/18/2008 6:21:24 AM

Rodney

Posts: 688
Joined: 5/23/2007
From: Central Oregon
Status: offline

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.

_____________________________

1968 FLH owned for 30 years
2002 FXSTDI

(in reply to hddee)

Post #: 4

RE: trying to tune a cv - 5/26/2008 8:32:39 AM

jmetro

Posts: 243
Joined: 5/29/2007
Status: offline

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.

_____________________________

(in reply to Rodney)

Post #: 5

RE: trying to tune a cv - 5/26/2008 9:24:49 AM

megawatt

Posts: 297
Joined: 12/7/2007
Status: offline

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.

(in reply to hddee)

Post #: 6

Page: [1]

Harley Davidson Forums >> Harley Davidson Motorcycles >> Classic >> Shovelhead

Jump to:

Today's Posts
Most Active Topics
Make A Donation
Forum Rules & FAQ
RSS Feeds

Featured Sponsors

Advertising Info

New Vendors
Warehouse Direc
Baker Drive Train
Haulen Ass
Pickard USA
Harley Goodies
Pickard USA
AMSOIL - Performance Oil Technology
Brain Bucket Magazine
HDForums.com Sponsors
AMSOIL - Performance Oil Technology

HDForums.com is not affiliated with or endorsed by Harley Davidson, Inc.