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Will new exhaust, effect motors tuning?

7758 Views 9 Replies 6 Participants Last post by  jrick56
I just ordered an aftermarket set of slip-ons, I am absolutely stoked. However my good friend suggested that I may need to have a pc3 to allow for the additional air flow or risk damage to the motor. I think the computer will compensate for this, he does not. Neither of us are experts to say the least so I’m looking for some thoughts from others that have gone down this road.
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Generally, a slip on doesn't require a Power Commander. Will you be able to eek out extra performance gains? Sure. But damage to the motor is a bit overboard. Sounds like someone sold your friend on a PC pretty hard. :p
Every bike is different to some degree. These bikes come running lean to begin with for environmental law compliance. Adding a less restrictive exhaust will only make it leaner. The problem is that if it's too lean it can damage your motor.
my stock 2010 has what i think is a lean stumble just off idle notice it a lot when cornering semi fast .talked with afriend who put a pcv on his new bike (fjr) because it was doing the same thing . he said the remap took care of it. i'll have to wait for a while to save up for mods. first will be the ugly fender. rick:D:D:D
Every bike is different to some degree. These bikes come running lean to begin with for environmental law compliance. Adding a less restrictive exhaust will only make it leaner. The problem is that if it's too lean it can damage your motor.

This is very good info. I have thought about exaust upgrades but I dont wanna pay for the new exaust then pay for motor repair not long after.
hey guys, just wanted you to know that when i dynoed my stock 2010 z it showed very lean on boyyom very rich on top. said we could get better power by richening bottom and leanining top. if you add slipons to an already lean low end it may lean it more. top numbers might get better. but i don't always ride above 7000. just a thought. read my other post.
my friend has a new 2010, 2 bros slips, no PC dyno said no problem.
my 2004 muzzy full system no PC got richer down low after the switch from stock. go figure. my gas millage went down slightly after the change.
how weird is that. but you did check it out. i hate the not knowing.someone posted on here that their bike didn't need a pc after a full exhaust. also with a dyno. maybe i'll check mine before and after if i can. but i'm also changing filter. very bike i've had that i changed both ran lean after. still always best to be sure.
all emission control engines [ car, truck, bike] are still a little rich on full throttle to protect the engine from being lean and doing damage. in open loop pre programed settings keep it slightly rich. so if you add a mod to increase performance you go closer to being lean. a lot of the time the A/F ratio is close to perfect . a PC will help mostly in slow and mid range performance. slightly rich or lean will not harm the engine. even after mods sometimes the dyno operator will use the PC to lean out the A/F ratio some more over stock to make more HP. the word in drag racing is LEAN IS MEAN to a point. even a slightly rich A/F ratio will make less HP than a slightly lean A/F ratio. i have never worried about about riding after slight mods without a PC.
i road my victory 8 ball for 2 years and even drag raced it without a PC or re map of the computer. after 2 years i did do a computer re map [ same as a PC. you are altering the A/F ratio. most motorcycles you must use a PC to change the A/F ratio. harley and victory use down loads or PC. a lot of PCs are sold to riders that do not need them. what i would do is do the mods and pay a bike dyno shop to do a dyno pull with a A/F ratio reading 50 bucks and find out if it needs a PC.
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i agree with you about slipons but if you change intake and exhaust the chances are better that you'll affect a/f. your advice to check is right on. my bike is way too rich on top. and lean down low, stock. wiith muzzy and bcm filter will probably be close on top. may or maynot be leaner on bottom. will be checked. pc many times just adds a hp or 3 with fine tuning. still, if you tune on a hot day it won't be the same when it's cold. the autotune system sounds like a promising update. supposed to maintain pre set fuel maps all the time.
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