Changing Aftermarket Exhaust...

[Shee_Man]

I'm switching my DG pipes and silencers to Pro-Circuit pipes and silencers... I'm also adding a Noss Coolhead and V-Force 2 reeds... my jetting seemed spot on before... I have no clue what it is though...

 

I was also planning on installing a K&N filter with adapter plate and remove the lid... this would for sure affect jetting though... including this I was advised to run 310 mains and 30 pilots (is this ok?)

I bought the jets but all the screws holding the carbs together were tightened by a freak and I can't get them undone. ::

 

If I don't change filters will I be ok with the pro circuit pipes, reeds and Noss head over my original jetting for just DG pipes?

[locogato11283]

no. you will have to jet up. simply adding the v force will need rejetting. id do all the mods and jet up a few sizes. if you dont have a good air filter the v force arent gonna do you that much good. theyll only flow as much air as you can get to them. so while you are doing those go ahead and change the filter. what is your sea level and we can get you close to what your jetting needs to be.

[lincster]

Anytime you change anything, you have to check your jetting.

You need to get those screws out.

Just because your bike runs good now, doesn't mean it will run good for long... I am saying this because you don't know how you are jetted now.

 

"A lean bike will run good, just not for long"

[sredish]

Banchetta pointed out to me once that adding reeds will actually richen the mixture on some occasions, causing you to have to lean your jetting some. i thought this was peculiar, but it makes sense if you think about it. Your getting quite a bit more airflow. The added airflow will draw more fuel, and in some cases, so much that you'll have to back off your jetting a little to compensate.

 

I'd say, just from what I've heard about the DG's is the Pro Circuits will flow more and you might have to jet up a size or two, but then the reeds could possible richen it some, and you might be somewhat close. As you can see, jetting for each bike can be totally different, and ANYTIME you make a change, you'll have to rejet and read your plugs. NO ONE can tell you exactly what you need to do.

 

Good luck and let us know if we can help.

[Shee_Man]

sredish... that's exactly what i've heard and assumed... since the DG's are aftermarket there won't be a HUGE difference between the procircuits and them in jetting... and the reeds are supposed to richen it a tad (normally a clip leaner on the needle)... so since the jetting was good before... I should be fine still... if not I should be fine to test it out and check my plugs right?

I won't burn up my engine right away at least?

[FadedDreams]

When i had Pro Circuits and V-Force,i was at 310 main and 30 pilot,and it was slightly rich.But not enough to effect how it ran.I'm at 1700 ft.

[sredish]

sredish... that's exactly what i've heard and assumed... since the DG's are aftermarket there won't be a HUGE difference between the procircuits and them in jetting... and the reeds are supposed to richen it a tad (normally a clip leaner on the needle)... so since the jetting was good before... I should be fine still... if not I should be fine to test it out and check my plugs right?

I won't burn up my engine right away at least?

I haven't read what main your running now and your elevation, but my Fatties, w/ VForce, was at 320 & 27.5. I'm going to say your mains are going to be between 280 and 310, and it will depend on how your airbox is setup and your elevation. If you add a K&N and remove the lid, I'll bet you'll be more like 290 to 310, but once again, all machines run differently and you could go either way. That's just from my experience. I have seen people running fatties and no airbox with a 280, I didn't look at their plugs, so I don't know, but don't be afraid to richen if necessary. Worse thing that can happen when too rich is a fouled plug, worse thing that can happen when too lean, BOOM!

[Banchetta]

I think your fine for testing and I'd do it..Slap them together and run it for testing. Check your plugs and fine tune the needles and air screws...I'd think your real close to the jetting you need. I've had good experience w/ pc pipes as well as every other pipe on the market exept for rocket, dg, cpi, and shearers. Most jetting is pretty close and within 3-5 sizes...Your a little richer than I'd start w/ for pc pipes, so roll w/ it. Keep us posted.