getting ready for coil on plugs and a carb redo

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apsolus

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hello friends. my bike has been sitting a couple weeks while ive been busy racing. anyway i really miss having a lady on the back and hitting the road so im planning on pulling the plug on a few items like coil on plug kits and a carburetor rebuild kit. ive been told that contrary to popular belief with these carbs you want to jet down and not up. does anyone have any specifics on this? the bike has a k and n air filter and kerker slip ons, and a dyno jet stage 1 kit. everything else is stock. it would be nice to just order a good known carb kit and install it. ive still got all the stock carb stuff.
 

Fire-medic

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[email protected] Sean Morley's kit for "More (ly's) Muscle"

The Stage 1 Dynojet kit doesn't seen to do-well, the Dynojet Stage 7 kit works with a full (complete) aftermarket exhaust, and a bit of tuning to ensure it's working as it should be. The Morley's Muscle is better for normal use, it has a good midrange increase instead of a top-end balance with less-satisfactory midrange. Exhausts need to be larger header pipes to take advantage of the different jetting, and a less-restrictive (read, 'louder') canister or two. The complete system 4/1's usually work best at the strip, the 4/2's are good for being a bit quieter (two mufflers instead of one).

Sean Morley can also sell you a Mark's complete exhaust, I think Mark isn't making a 4/1 now, just the 4/2, check with Mark's Exhausts or with Sean Morley. Star Rider Performance is Mike Lees, who is operating on his own after being with UFO Performance (Jon Cornell, deceased) and they have a variety of ear-splitters (Quad-Zilla (4-into-4) and Dragstar (4-1) and some more-quiet ones (4-2) but they're all pretty-loud. VooDoo is similar to what was UFO. Delkevic has a number of offerings.

You need to understand that without the larger 4 header pipes (and whichever end(s) you choose), the jet kit is not what you want. It's like marrying a pair of Siamese twins: they gotta go-together. I suggest if someone suggests Cobra 4-into-4's that you politely decline their advice, and choose another shop. Why? I'll leave you to use the 'advanced search' in the upper right-hand corner, for 'Cobra' "Cobras' or 'Cobra exhaust'.

I forget where you are. If you add that below your screen name, I won't need to keep-asking. Usually the USA market bikes, unless the bike was sold in Denver CO or a similar altitude or higher, main jets are 152.5 Mikuni. You can probably go to 150 or 147.5 Mikunis, and the bike will run-better, with a full exhaust, assuming you aren't 'way-above sea level. Be aware Dynojet main jets have a different #ing system than Mikunis. 'Advanced search' for info and charts.
 
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MaxMidnight

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'Fraid there isn't any magic formula here particularly as you have added two variables in the filter and exhaust.

If you want to get the best out of the motor and not spend time messing with changing the jets then you need to remove the guess work on what the fueling is doing.
This can be done by plug chops but that depends on your ability to read them.

IMO having a baseline dyno run will give you the facts to understand what the a.f.r. is doing throughout the rev range and give you a base to plan your changes.
 

Parminio

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the bike has a k and n air filter and kerker slip ons, and a dyno jet stage 1 kit. everything else is stock.
Unless you're changing the exhaust to a full exhaust system, don't touch it. You'd just be putting the bike in the same shape it's already in.

As mentioned above, you need to match your components and as far as that goes you're pretty much already there.
 

apsolus

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'Fraid there isn't any magic formula here particularly as you have added two variables in the filter and exhaust.

If you want to get the best out of the motor and not spend time messing with changing the jets then you need to remove the guess work on what the fueling is doing.
This can be done by plug chops but that depends on your ability to read them.

IMO having a baseline dyno run will give you the facts to understand what the a.f.r. is doing throughout the rev range and give you a base to plan your changes.
i feel like a dyno run would be the quickest was to figure out what i need
 

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