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is there a good jetting manual around? an easy 'how to' form or something. what have you guys used in the past? is it even something i can attempt, or should i leave it for a professional?

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Your best bet is to post your current jetting, elevation, stock or aftermarket pipe, whether you have done the 3x3 mod, and wait for Burned to reply.

Easy nuff.

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is there a good jetting manual around? an easy 'how to' form or something. what have you guys used in the past? is it even something i can attempt, or should i leave it for a professional?

You can do a search for Dynojet 3x3 and Burned's Dynojet FAQ. for all the info and a Mikuni jetting chart is available in the TT store.Also jetting info at Sudco and Carb Pars Warehouse sites as well as drz.info/drz/

BayouBikeBruiser had a really good thread on it a while back if you search his posts.Also check the Jetting Forum for good tips as well.

http://204.71.0.3/motoprof/moto/mcycle/carb101/carb101.html

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Your best bet is to post your current jetting, elevation, stock or aftermarket pipe, whether you have done the 3x3 mod, and wait for Burned to reply.

Easy nuff.

my current jetting is bone stock, my elevation is 0-2000ft, i have a yosh rs3 full system and have done the 3x3 hole.

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i went through the jetting pages (like 30 now) and compiled a recipe for my mods and conditions. you can do the same, and in doing so will gain knowledge. jetting is still very sketchy for me. i know the basics but eddie is the fall-back guy.

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Here's this for a starter. It's the setup for the Mikuni that comes with the S

Burned's FAQ for his DynoJet kit setttings(for the 3x3 air box hole)

Q-What main jet should i use?

A-140 main for the stock muffler(stock or modified end cap).142.5 for

aftermarket pipes.

Q-What needle position should i use?

A-4th clip from top.

Q-What pilot jet should i use?

A-25 pilot.

Q-Where should i set the fuel screw?

A-2.5 to 3 turns out.

Q-Can i use the stock pilot jet (22.5)?

A-Yes,but since you must run the fuel screw out past 3.5 turns you run

the risk of the screw falling out.the lack of spring tension makes it

possible for the screw to vibrate out.

Q-The picture in the kit shows the clip position as clip 3,but the

instructions say clip 4.

A-The picture is wrong.4th clip from top.

Q-Why doesnt the kit come with main jets big enough for your settings?

A-The kit was developed for the the stcok unmodified air box with the

snorkle removed.When you enlarge the hole to 3x3 the main jet must

be enlarged.

Q-Why doesnt the kit come with the 25 pilot?

A-Again,the kit was not developed for the 3x3 hole.

Q-$60 dollars is alot of money for a needle!

A-Yes,it is!But you also get a softer slide spring.The initial price

shock will fade quickly when your bike pull way harder than you

expected!

Q-The main jets settings sound way lean.Im using the 150/27.5 jetting

now and it isnt rich.Im afraid my bike will blow up.

A-The end demension of the DJ needle is much smaller than the stock

needle.Therefore it block the main jet less enableing you to run a

smaller main jet.A 4 stroke that is lean enough to hurt itself will

not run correctly.It is very obvious when it is too lean.It will miss

fire severely at high rpms.I assure you my setting are safely rich.I

cannot control the fuel quality available across the country.I

compensate by suggesting slighty rich main jet settings.My personal

bike would run leaner main jets yet.

Q-Why 25 pilot and not the 27.5 pilot.

A-The 27.5 pilot is used to cover up a stock needle that is to big of a

diameter (lean)on the straight portion.the straight portion is being

utililized off idle and at low rpm steady throttle.With the correct

needle diameter the pilot jet can now be reduced.This has a couple

benifits.One is the fuel screw being 2.5 to 3 turns out has a broad

range of adjustibilty.Fine tuning is much simpler.The other befinifit

is excellent fuel economy is maintained since a rich pilot isnt needed

to overcome a lean needle.

Q-I ride over 5,000 ft in elevation and never lower.What main jet do

do you suggest?

A-128 main jet stock exhaust (with or with out end cap mod),and 130

main jet for aftermarket exhaust.

Q-Do i need to change the needle position for high altitude?

A-No,one of the advantages of the CV carb is the sensitivity to

altitude only requires the main jet to be changed.

Q-What about the pilot jet and fuel screw setting for nose bleed ville?

A-There again,only slight changes in the fuel screw setting may be

required.In most cases the setting stays the same.

Q-Why is your set up better than the 150/27.5 jetting?

A-Since my settings are based on the DJ needle and spring a proper

balance can be attained.Since you are no longer relying on a overly

rich pilot and main jet.When a needle with the correct demension is

used the main jet can be tuned for peak performance and the pilot jet

can be set for optimum economy.

Q-Why cant i just shim my needle?

A-Shimming the needle does nothing for the straight diameter of the

needle.The stock needle is very lean off ilde.While shimming the

needle does richen the steady throttle at high rpm's,it cant change

the fact the straight portion (root diameter) of the needle is too

big.It can also do nothing about the needle having to slow or shallow

of a taper to have a proper fuel curve.

Q-Will my fuel milage go down?

A-No,and in most cases it may improve.There again the overly rich main

jet and pilot jet are being done with out.

Q-DynoJet say there jet number do not coincide with Mikuni jet numbers.

Do i need a 140 or 142 DJ jet or Mikuni jet?

A-They are the same!A 140 DJ jet is the same as a 140 mikuni.Dynojet is

in the business of selling jets.Its much more profitable for them to

make their own jets than to buy them form mikuni or kehin.I have

the DJ and Mikuni jets with number drills.they are the same!

Q-I called DynoJet and they said it will never run right with the 3x3

hole!Whats up?

A-Do not ever take what phone monkeys say as the truth.They are on

phone duty for a reason.When DynoJet developed the kit for the S

decided that the stock air box hole would satify most S owners.they

did not feel they needed to take the extra time to develop what would

essentially be a stage2 kit.I have taken the time to develop the

setting.S owners are more performance oriented than DynoJet

predicted.They have since moved on to other projects.They are on a

never ending development process with new models.Between the huge

ATV market and the time they spend with fuel injected stuff they have

no time or desire to go back and revise the kit.

Q-My bike pops on deceleration.It must be lean!

A-NO!!!!!!!!!!A motorcycle with a properly tuned pilot circuit will

have a slight pop on decel.Heavy explosions in the exhaust pipe is

caused overly rich pilot settings and or exhaust leaks.

Q-I just put aftermarket pipe on and now it pops on decel.It must be

lean now.

A-It always popped,you just couldnt hear it with a stock muffler.

Q-After installed my kit the bike ran a for a second than died and wont

restart.Any ideas?

A-Its very common for the vacuum hose for the petcock to be missed on

reassembly.Make sure the hose is connected to the port on the carb

and petcock.

Q-With the kit installed,my bike wont idle and feels really lean down

low.Whats up?

A-Alot of times the manifold between the carb and head isnt sealing

properly after the wrestleing match.Make sure the carb is fully

seated in the boot.Also confirm your fuel screw setting.

Q-The idle seems irratic.Whats the proper way to tune the fuel screw.

A-With the bike at operating temp,turn the fuel screw in till the idle

misses.Slowy turn the fuel screw out till the idle is smooth.

Q-After i installed the kit,the bike idles fine and sounds good on the

stand,but wont go down the road!feels like a sick xr100!Now what?

A-The slide spring is cocked in the carb cap and the slide cannot lift

or the main jet is laying in the float bowl.

Q-After i installed the kit i cant keep the front wheel on the ground!

Why?

A-With the combination of proper jetting and the DJ slide spring the

carb now works properly.You will be blessed with huge wheelies!:thumbsup:

Q-What makes you such a smart guy?

A-Im not sure,but it might be the lead paint on my baby crib.My mom

also says my dad used me to check Lucas magnetos for spark when i was

a toddler!You take your pick!

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