New Exhaust Rejet

I have a 97 Road King...Carb and exhaust are factory orig....I want to buy a set of Vance and Hines Big Shot Duals (sound, looks, and value make these the choice for me)...What are the current jets in facotry carb and what should it be rejetted to? is this an easy task?

THANKS!

I'll be the first to say you should get yourself a service manual if you don't have one. Carb jetting is relatively easy, just follow directions, but you may not need rejetting depending on what you're jetted for now. Have you changed to a higher flow air filter (K&N, Hypercharger or such)? You should do both together to increase and balance the flow.

You'll likely want to increase fuel flow, which will be needed once you increase the air intake and reduce the exhaust pressure. You may be able to tune the carb through the jet's adjustment screws without rejetting. But don't run an engine too lean for too long, as it is far worse on the engine than starting too rich.

We need an EVO guy to give you the factory jetting.

Thanks Gents....I do have a shop manual (and will look through it when I get home)...and I did put a K&N filter on a couple of years back...Will that make a difference within the carb? Should I have done something with I installed the K&N filter? sorry for the questions, but I just want to make sure this exhaust mod it is done correctly and also try to aviod a trip to the dealer or shop (but am willing to do if necessary)

THANKS AGAIN!

Yes, the K&N filter allows for more air flow which will lean you out considerably. When doing mods, especially with the air, a rejet is always needed. Doing pipes alone usually doesn't require a jet change. I would follow HarleysLR suggestion for jet size. A 45 is way small. I have a 46 and 185 in mine and I have a Sporty...

Uh, I'm running a 45 slow in my 95", and it really isn't a problem. Running a 195 main, and likely to downsize if I can't get it leaner (break-in jetting needs to be rich) through tweeking.

Whatever, the individual jets aren't much in price, so feel free to replace 'em and play with the settings. Just be careful of running too lean.

Altitude??? Aren't you running a stock air cleaner as well?

Nope & nope. Altitude should make me run richer (more fuel to air ratio), so I should need even smaller jets. And I've a K&N/SE breather set-up.

:cheers:

just to let you guys know there is a person on ebay that i have been getting my service manauls from for the last two years he has them on cd and he sells them for 7.00 dollars including shiping and i load them on my lap top . beats spending 60 bucks and they are hd factory manuals on pdf format.jmo not bad for 7.00 got my bagger and softail manual in a weeks time

Update...Finially have time to install V&H big shots this weekend and did some looking and research - my Road King has 42 pilot and 175 main - I also have an K&N filter....think I will start with 48 and 180?

Sound okay? any help would be appreciated

bingo!!!!!!

Thanks for the help gents....one last question...which sportster needle do i get? Im confused by that....are you talking about sportster needle for a sportster modle HD or something different? I have everything I need to do this tomorrow, but that needle....dont want to make this a 2 weekend project.....THANKS AGAIN

and is changing the needle to a sportster absolutly necessary?

Musta be a Californee model...my '90 Softail came with a 45 and 185 and the Cali's had a 42 and 165.... can't see the baggers being jetted leaner
The Sporty needle is the N65C (27092-88)I think it may be obsolete now....altho CV performance now has one..
If it's the stock breather with a K&N filter a 48 is probably too fat,even with a high flow breather kit(backing plate and filter)...start with the 45 and get your idle mix adjusted no less than 1 turn in or 3 1/2 turns out....if your best idle is between there your pilot jet is good...

Idle Drop Procedure
Bring the bike up to operating temperature. Make sure the enrichener is off. Turn the idle speed down using the idle SPEED adjustment screw (the one by the throttle cables on a CV) until the bike is only barely able to stay running, maybe a little higher than that. 800 RPM is a good RPM if you have an accurate tach. With the RPM lower than normal, you will be able to see the effect that adjusting the mixture screw has.

The idea is to turn the mixture screw in until the idle speed drops, then turn the screw back out until the idle speed drops again, and set the screw in the middle of those two points. What you are doing is making the mixture leaner, so lean that the engine does not like the mixture and runs poorly, then you make the mixture richer until it doesn't like that, and the perfect setting is half-way between the point where is falls off either way.

A couple things to remember
1. If the bike gets overheated during this procedure, you will need to let the bike cool off a bit and try again. If you are already at operating when you start this procedure, running more than about 5 minutes while trying to get the setting correct will make the bike too hot. If the bike is too hot when you set the idle mixture, the final setting will be too lean.

2. The screw should be set at least 1/2 turn out from fully seated, and no more than 3 turns out. If it is less than 1/2 turn out from fully seated when it runs best, you should install a smaller pilot jet and perform the idle drop procedure again. If it is more than 3 turns out, you should install a larger pilot jet and perform the idle drop procedure again. If the screw ends up more than around 3-1/2 turns out from fully seated, the spring tension on the screw is insufficient and there is a chance the screw can vibrate out.

3. A tachometer is helpful for seeing the rise and fall of engine RPM if you are not comfortable listening for the changes.

4. The enrichener should be completely off to perform this procedure.

5. An intake leak will foul these results. If the mixture screw seems to have no effect, you may not be able to perceive the change in idle speed, there may be an intake leak, or you may already be either too lean or too rich and you need a different size pilot jet.

WOW! I dont have a tach, so it will by by sound...and I went to my local HD dealer and they suggested to start with 48 for pilot and 180 main????...never mentioned needle jet

A 48 will mask a too lean off idle where your needle jet comes into play(1/4 throttle)The proper pilot jet and idle adjusted right and you can get a carb fart,because the needle jet is wrong,that's where the N65C needle comes in...it's from the '89 Sporty with a CV carb and no accelerator pump so the taper on the needle is a little richer than the taper on your stock needle...

Here's some more info with pics...

Harley Davidson Carburetor Performance Tuning

Then check out rejetting your carb