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Discussion Starter #1
I originally had the dealer do stage 1 with a dynojet kit before I picked up the 2001 dyna. Since then I've changed out the SE II mufflers with Cycleshack and every since I get lots of decel popping and it even backfires sometimes running up thru the gears. This surprises me cause I would have thought the SE II's and Cycleshacks would have flowed about the same.

Since I can't get rid of the symptoms with the idle mixture screw I'm going to have to go into the carb and I would like to back out the dynojet mod and just do the regular CV mods - jet,shim, drill the vacuum hole, etc (worked great on the wifes sportster).

The question is what exactly constitutes the dynojet mod, i.e. what stock parts will I have to get beforehand (spring, slide?) to bring it back to stock?
 

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Dynojet has offered several kits that contain different parts - some contain a new slide, some don't. On top of that, it might not even be a Dynojet kit since a lot of people refer to all carb kits as Dynojet kits(they were one of the first to offer the kits).

I doubt that the carb kit is the source of your problem. Are the Cycle Shack pipes slip-ons or complete length pipes? An exhaust leak at the head will cause backfiring. Hold a rag over the end of each pipe while the bike is idling and listen for leaks. An intake leak will also cause backfiring so test/inspect intake seals.
 

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Discussion Starter #3
Good point. I'll check the exhaust port flange bolts when I get home. These are slipons but I really socked down the clamps so they wouldn't creep so I don't think it's at the header/muffler junction.
 

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I agree with the others that the Dynojet kit is not your problem(my opinion). My Deuce had the popping & intake cough when new, & got worse when I opened up the stock pipes & put on A K&N filter breather kit. I got the Dynojet kit that changes the jet, emulsifier tube, diaphram spring & slide needle. Cost about $70. It stopped all the previous problems I mentioned so I doubt it is the source of your trouble.

Check the intake manifold for a leak also , if it leaks ,your mixture will be leaner than normal. Try spraying a little carb cleaner or ether around the manifold when it's running & see if the revs jump up!;)
 

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Check the intake manifold for a leak also , if it leaks ,your mixture will be leaner than normal. Try spraying a little carb cleaner or ether around the manifold when it's running & see if the revs jump up!

Think this gets overlooked more than logic allows, made the mistake myself because the Revs didn't really jump that much when sprayed with carb cleaner .. Long Story Short after deciding to replace the Intake Manifold and Seals had to drop the Slow Jet from a #50 to a #48 because was running too rich simply because too much air coming from a slight intake leak ..
 

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Nice 17 year old thread resurrection!

Anybody know if this is a record?
 

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LOL
looks like gypsy92117 is new to the forum, probably didn't notice the last post date.
Still may be a record though.
Welcome to the forum gypsy!
 

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Guys do more things wrong to the poor CV than you can imagine. There is more stuff available to "fix" the CV than there are parts for a 57 Chevy. The kits are a waste and in some cases create issues. Do not drill the slide, use the stock spring and slide. Imagine that you started with an emissions setup, too lean after any airflow enhancements, on the bottom and midrange (pilot) and too rich on top (main). Reality is after the airflow changes the main becomes very appropriate and low speeds need help. Coughing out the intake = lean. Usually a mild 95" runs sweet with a 46 (drag specialties or CV products) and a few #4 washers under the stock needle. Drill out the plug so the idle screw is accessible and adjust to the best idle, no recipe number of turns. No sportster needles (too rich) which were designed for a CV with no accelerator pump. Above all KISS principle. After you are in the 95hp level its time to look for another larger carb to go further and kiss the CV40 goodbuy.
 
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