Harley Carburetor Jets

Question Hello and I love all the info from this site as I have learned a lot from it. I have a question about my carb. I have a 1999 wide glide twin cam 88. At low speed, in first and second gear, going slow I get a hesitation and popping back through the carb and it seems as it’s gotten colder it happens at around 55mph also. I’ve followed your video and took the carb apart and cleaned it but it makes no difference. The bike has a big sucker air cleaner and screaming eagle open exhaust and I noticed the pilot jet was a 42 and the main is 165. My clymer manual states that I should have 65 pilot and 190 main. I feel like it is too lean with the factory but I am unsure of such a big jump in size from what the clymer manual says. Should I rejet or try to find a stock air cleaner setup and see if that fixes the problem. What Harley carburetor jets should I use? Thanks for your time.
CHris

Answer Not exactly sure why your m/c was ever jetted so lean. 42 & 165 are small for most evolution motors. Anyway, assuming your intake is sealed and your carbs accelerator pump is functioning correctly; we would suggest moving up to a 46 or 48 pilot jet and a stock 190 main jet. Play with your mixture screw and pay attention to the coloring of your spark plugs. You really can’t get into any trouble. Good luck

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17 Responses to “Harley Carburetor Jets”

  1. Tim

    Got a 91 Softail. Previous owner said it’s cammed and now has SE heads on it. I purchased a pair of short pipes, make and model unknown. I believe they are 1 3/4”. After changing out the pipes I noticed a big difference in the way it runs and I get the popping when letting off the throttle. Just curious what size jetting I may need to go with to fix the issue

  2. Michael J Riddle

    Just bought 2005 Electra glide has stage 1 and now I live at 6000 elevation what size jets do I need for this elevation ?

  3. Ron

    2005 TC88 Pipes, aftermarket air cleaner. Just jetted to 48 slow and 190 main great throttle response but loading up and backfiring after hard run. Should I lower my 190 o a 180?

  4. Giuseppe

    Hello, i have a question about the carb of my 2004 Sportster Custom 1200....What are the stock sizes of original jets? Thanks, greetings from Italy, Giuseppe

  5. Michael

    I have a 1990 FLSTF with a ‘92 CV (non-California). Also running V&H pipes and Crane Cam. I recently added the pipes and rebuilt the card, leaving the existing Main Jet @ 180, but dropped the Slow Jet to 44 where I was able to get some response adjusting the fuel mixture resting now at two turns. A quarter turn in and she’s missing. She’s running good at two, but blows too much black - sooting up my fender. When I checked the plugs after the last jetting, they were grey with black at the tips. Dropping to 42 seems too low. Is this just an old Evo issue? Mike

  6. Jeff Chambliss

    Here in Southern Illinois a #48 pilot and #170 main works great. Have been to below sea level in New Orleans to above 12000 feet in west. No fouled plugs, no "coughs".

  7. Tom Perry

    what is the actual size of the pilot jets? mine has a 42 and after sitting for 3 years is completely clogged..I opened it up with a .020 bit but afraid to go larger without knowing the actual size. I am 60 miles from a dealer and would rather get it going now and pick up a new one later...Tom

  8. poppy

    my polit jet is a 46 and my main is a 190 and it has great power but it is flooding and my plugs are black and at slow speed it jumps like its all cam up but it is stock can someone help me with it please thinkyou poppy

  9. Duane Hoyt

    is a s&s carburetor a good carburetor on a 1999 88 twin cam

  10. Perry Williamson

    I got a 2000 stock wide glide and I got the same trouble re; the popping and the hesitation , and a got of trouble getting it to keep running I got a sneaking suspicion it running too lean. Other than this little problem everything is bang on. Spark plugs are looking good, anything else I should be looking at ? Beside the the obvious