I've been living with decel pop ever since I gotmy bike.Last weekendI did some mountain twisty riding and the POP and BLUBBER is always worsewhen doing such. WhenI give it a good hardfree rev, I get a loud POP like a firecracker.When I'mon amild to hard decel, especially when going down hill, I get that gurgling blubber sound. IfI get on a harder decel, I get POP's in between the gurgling. Once in awhile I get a cough out the carb, but this is lower priority and seldom. Other then that, the bikes runs .........GREAT!!!!!! I'm real happy with it!!!! Smooth, easy starting, and powerful!!!!!

I've already been through the tuning process once before. Idle mixture screw hadlittle to zeronoticeableeffect. It was responsive, and anything less then 1/2 turn in and RPM's would start dropping. I could turn the screw 4 turns out.After 1.5-2 turns, I saw little difference. I rode tested in 1/2 turnincrements. I believe bike to be stock with basic stage 1 kit. SEII pipes, and K&N air cleaner, with Harley football cover, open in back. Carb is original equipment, but with a thunder slide.Theneedleis installed per Dynojet with washer in the fourth ring if I remember correctly. It's been a few months, but I remember verifying this. Jets where 48 and 185 whenI got the bike. I tried going up and down on the slow first 45 and 50. The 50 showed no change. The 45 made it idle worse. I tired adjusting this out with theidle screwbut hadlittle effect. I might have to re-verify this. I also tried 180 and 190 main, still no change with pop or drivability. Considering guysI'm using the butt dyno for tuning and we all now how accurate that is!!!! Bike basically ran the same.

I'm thinkingit might be in tune? Another guy posted last week that he blocked his crossover and the POP went away. Are SEII prone to popping?

WishI had a stock carb to try, not sure I like the thunder slide? A baseline wouldhelp!!!!

I have the hot sporty needle, but not sure if it'll work with the thunderslide????

Lastly, any bike mechanics using the Innovateair/fuel meter????? http://www.innovatemotorsports.com/products/lm1.php They are extremely accurate with data logging capabilities??? I'm thinking about getting one.

Looking for help guys!!!
John[/align]

 

The Thunder Slide kit is way too much for your build...they are set to give more fuel to a engine with long duration cams and head work, this is your biggest problem. No SE pipes aren't prone to pop, they are very good pipes. Check for exhaust leaks and think about taking out the Thunder slide kit and replace it with a reg dyno jet kit or install it all back to stock with a sporty needle. The Sporty needle will not work with the Thunderslide kit. The 48 pilot is again way too big for your build.

Good luck

 

Doc is correct. I myself hate thunder slide kits. I use the standard dyno jet kit. Check for intake leaks as well, also check the fuel petcock for a vaccum leak. They are common to get a hole in the diaphram and give you a leak. 45 pilot, and the reg jet kit will work just fine I would start with a 175 or 180 main with clip in the middle slot and tune from there.

 

Cool, thanks guys! I didn't know what a Thunderslide was until I tore the carb apart, and noticed it didn't match the service manual. I don't have the stock parts, and I'm not at all sure what was removed soI will probably look on Flea-Bay for a take-off. Unless someone on the boardhas an extra for sale????

Glad to hear about the pipes! I love the sound of the SEII's, but will probably try the BCT in the future!!!!

Thanks again!!
John

 

I have a bran new never used 40mm C/V carb complete. They are $425.00 from Harley ....this one will cost you $275.00 plus frt.

 

Thanks for the offer Doc, let me think about it. My carb is the 27421-99c, what is yours?

John