Air fuel adjustment for exhaust change

[phillips2VMAX]

I am New to tuning bikes, ( a car guy). I have a 1998 MAX and it has a set of Kerker slip ons. Bike has stage I jet kit. I just removed the baffles on the mufflers to get that small block sound ( it worked btw). Now I am sure I am running little lean, but don't know how to adjust the carbs for the change. Do I have to go to a shop with a sniffer to do this or is there a rule of thumb adjustment?

Thanks,

Scott

 

[Buster Hymen]

I am New to tuning bikes, ( a car guy). I have a 1998 MAX and it has a set of Kerker slip ons. Bike has stage I jet kit. I just removed the baffles on the mufflers to get that small block sound ( it worked btw). Now I am sure I am running little lean, but don't know how to adjust the carbs for the change. Do I have to go to a shop with a sniffer to do this or is there a rule of thumb adjustment?

Thanks,

Scott

With the slip ons and a stage one you shouldn't be running lean. You might even be running a bit rich. Slipons don't require any rejetting.

 

[shawn kloker]

You could also move your needle clip one notch in to richen the midrange a little ,open the air mixture screws 1/4 or 1/2 turn to richen the bottom a little.The mains should already be 152.5 mikunis wich should be fine.Is this an american version with full power?Tuning actually should be done by inspecting the plugs and road testing.I ran mine for a little while with a full aftermaRKET EXHAUST and stock jetting and it was fine.If it pulls hard the whole way to redline on the highway the mains are not too small.It will sputter and caugh on the top end from starving for gas. Shawn

 

[Redux]

I have a related question. Mine seems to running a bit rich (down low at least). If I add a K&N airfilter would that lean it out a bit or make the richness worse? That seems easier rather than tearing into the carbs. I say it is running rich because a slight smell of the fuel can be detected when the bike is just warmed up. Yes, the choke is off.. lol.

 

[maleko89]

It would lean it out everywhere if you removed the "Y" portion of the airbox. I would check for a dirty air filter and blow out the idle circuits using the shotgun procedure.

 

[firefly]

I have a related question. Mine seems to running a bit rich (down low at least). If I add a K&N airfilter would that lean it out a bit or make the richness worse? That seems easier rather than tearing into the carbs. I say it is running rich because a slight smell of the fuel can be detected when the bike is just warmed up. Yes, the choke is off.. lol.

You really can't gauge how rich the carbs are just by smelling the exhaust, the best way is to check the spark plug color.
a sniffer tuned stock bike will run like **** until fully warmed up then will be very crisp and responsive, it will fart from the carbs when cold if you blip the throttle.
________
Captiva

 

[mkunert]

Sorry, not quite sure of the last response. My bike coughs up the carbs sometimes, but I need to notice if the engine's warm or cold. For some reason, I think when it's warmed up, but I could be wrong. I have a K&N and the T removed from the airbox. Am I running rich or lean? What do I do to correct that?

 

[Buster Hymen]

Sorry, not quite sure of the last response. My bike coughs up the carbs sometimes, but I need to notice if the engine's warm or cold. For some reason, I think when it's warmed up, but I could be wrong. I have a K&N and the T removed from the airbox. Am I running rich or lean? What do I do to correct that?

If the T you are referring to is the removeable piece on the top of the airbox, you should put that back on. It has been proven that running with it off, causes carburation problems.

 

[mkunert]

It used to cough much more with it on. It seems to run much better with it off. I'm assuming it was running rich, but I'm not sure.

 

[shawn kloker]

A well tuned vmax will run like **** till it is warmed up.Removing the Y will lean it some from more air.Reading the plugs is the best method.