Tire Size

Discussion in 'Softail Models' started by dj culver, Jan 17, 2011.

  1. dj culver

    dj culver Member

    I have a '99 Harley Fatboy that has a lowering kit (2-3"). At the end of last year my wife and I took a short road trip together. She is only 140 Lbs and I am 180 lbs. When ever we would hit a small bump, we noticed that my ride "bottomed out" or was rubbing on what we thought was the fender. In looking closer, I noticed that the outside of the tire itself seemed to have some uncommon wear apparently form rubbing on the belt. I inspected this and saw that the tire when no rider was on, was only about 1/2" away from the belt. I adjusted my air pressure to accommodate the extra weight (40 psi), to no avail. I thought that my shocks were going bad as they are adjusted full out.
    In looking at this closer, I noted the tire size that is on there now. It is a 140-90 B16 m/c 77H. In looking at the PDF that another member of this forum posted, I see that the stock tire for that make and model is a 130-90-16.
    Is it possible that the difference between a 130 and a 140 is drastic enough to cause this tire to rub? I am now wondering if the "rubbing sound" or bottoming out is also caused by this difference in tire size? I would welcome comments from any one with knowledge on this subject! Or any comments at all. It would save me a lot of guess work and unnecessary parts replacements. I don't want to have to fork out $300.00 for a new set of shocks if the ones I have are fine. Thanks in advance for any input!
    DJ Culver
  2. Mad Dog Jim

    Mad Dog Jim Banned

    One way or the other you need a new tire right? Get the stock size and I bet that fixes it.

    also look at your left saddlebag andsee if the wind is blowing it against the tire. You might need supports to keep them off the tire

    NEWHD74FAN Experienced Member Retired Moderators

    Welcome DJ to the H-D Talking forum. As you may have noticed going from 130 to 140 means 10mm total or 5 mm each side. Add to that, possible accessories and riding too up, it is very easy for the tire to rub on the metal wire loom keeping the taillight/license plate wiring from fouling up in the tire tread when going over a heavy bump. The other thing might be wiring has already "chafed" the wiring under there, so do take the time to verify proper lead dress and connections.:s
    Last edited: Jan 18, 2011
  4. JBC2565

    JBC2565 Junior Member

    Spec on a '99 Fatboy for rear suspension travel is 103 mm (4.1 inches).
    I've got a buddy that runs a 150 on his Fatboy ('97) and that is way too tight for my liking. Not much more than 1/16" from the belt.
    See how much play you have in the rear suspension and go from there.
    Not sure how lowering 2-3" would affect the travel.
    Check the suspension bushings as well to see if you have any "slack". Might not be engaing properly.