popping in the exhaust

Discussion in 'Touring Models' started by ultraclassic, Oct 18, 2007.

  1. ultraclassic

    ultraclassic Member

    7
    11
    0
    I have an 04 ultraclassic with EFI. Lately when riding the bike feels "rough" and there is popping coming from the exhaust. I was thinking that the fuel mixture is too rich but am not sure. Additionally now the bike vibrates more then it did in the past. 1) is there a way to manually adjust the fuel mixture if it is too rich without taking it to the shop. Also, I have a trip coming up on Sunday that is roughly 2500 miles. Will this deteriorate the engine at all and is is safe to ride.

    thx,
    AF
     
  2. glider

    glider Veteran Member

    25,464
    108
    43
    Looks like Hobbit has it covered. :D

    Just a few more things, make sure the plug wires are all the way on and that the spark plug tops are screwed on tight. A new set of plugs wouldn't hurt either.

    Also with popping out the tail, the exhaust gaskets may need some attention or the pipe flanges could be loose too.
     
  3. Zamadan

    Zamadan Active Member

    195
    26
    0
    Sounds like I had a similiar problem for a little while. Sputtering popping and backfiring when reducing rpm's. The main cause was filling up before the tank was too low. The gas stations I went to had the three fuel selection on one pump. The problem with selecting premium is that you are putting in a few litres of regular before the pump starts putting out the premium. If you top up the tank regularly you end up with more regular, low octane in the tank. The regular gas was in the hose all the way back to the pump intake. Now I have a few stations that have a designated premium pump and have not experienced a problem since. Love the Chevron 94 down south, extra power, or so it seems.

    Just learning a little, day by day, year by year, still smiling :)
     
  4. glider

    glider Veteran Member

    25,464
    108
    43
    Some food for thought...

    Assume a gas hose is 3/4” diameter hose by 10’. That makes a gas hose a really long and skinny cylinder. We want to know the volume of that cylinder. It’s easier to do the math if you have like units, so, in inches that’s 0.75” x 120”.

    We know that cylinder volume = pi * radius squared * height. Or, if you like using the diameter, 1/4 * pi * diameter squared * height.

    I used the radius formula. Of course we know radius is 1/2 the diameter so 0.75” / 2 = 0.375”.

    Up with me so far?:cheers

    So, 3.14 * 0.375 * 120 = 141.3 cubic inches.

    Now, 1 cubic inch = 0.554112552 US fluid ounces.

    So, 141.3 cubic inches * 0.554112552 ounces per cubic inch = 78.2961036 ounces in that 3/4" x 10’ hose. Let’s round that off to 78.3 ounces.

    We know that there are 128 ounces per gallon, and 32 ounces per quart. Assuming the hose was completely full, at most, you are looking at 78.3 ounces of unknown octane rated gas.

    That is because 78.3 / 128 = .62 (rounded). 62% of one gallon or 128 ounces is 79.36 ounces or just over half a gallon. In context of drinks, that’s 2 quarts or Gatorade and a 16 ounce bottle of soda leaving the last swallow in the bottle.

    But this assumes there is a maximum volume of gas in the hose.

    In actuality, the gas valves incorporate a vacuum relief valve and there is likely no gas in the hose except for residual wetness which is of little to no consequence.

    There ya have it!
     
    Last edited: Dec 6, 2007
  5. Not Very PC

    Not Very PC R.I.P

    527
    28
    1
    Yea but which hole did the rabbit go in? :shock
     
  6. glider

    glider Veteran Member

    25,464
    108
    43
    The left one!:D:bigsmiley8:
     
  7. Not Very PC

    Not Very PC R.I.P

    527
    28
    1
    There you go and oil in the right!!
    You must have owned an Indian at one time or another :s
     
  8. ultraclassic

    ultraclassic Member

    7
    11
    0
    Great thanks!