No issues with low profile tires on my bike after 9000 miles at lots of high speeds but I have the 17/200 on the rear. Just installed my second LOW profile Metzler XXL 200/50 zr17 and it handles great. Only problem is the price on that fat tire, holy crap! I'm going to try to ride this one a little more conservatively to get some more miles out of it.

I agree that Coastal Moto is terrific to deal with.

I know there are lots of guys with 21/18 on '09s that have no issues so not sure what it is. Definitely sounds like in your case the variable is the size of the wheel. My buddy has an '08 with 21/18 and he rides the crap out of it with no issues.

 

I have an 09 and run a 21/18 combo ( Avon rubber) with no problems. Rides just like it did with stock on it.

 

I'm running 21 / stock 16, bike lowered, no problems at all at any speed, straight or curves. I plan to have my rear wheel chrome plated when I extend the bags to make it look better, I just hope I don't scuff the bags.

 

I would be very interested to here how this lowering kit works out for your buddy. I have 2009 street glide with 21/18 combo and running ME 880 / 200 on the rear. I am also getting some high speed wobble at 80 + mph on straight runs. I sometimes notice it very little around 75 mph. Again I also just ordered Race Tech spring and lowering kit with gold emulator valves. Plan to lower mine 1".

 

always had a 21 and 18 and never once experianced anything like that. and i have been up to a 105 +.

 

any of you guys with the wobble checked your neck bearings? just curious.

 

I was lane splitting yesterday on the 5 south here in San Diego with a member of a club that will remain nameless. He was on his Dyna, me on my RK, 95-100 I could barely keep up. LOL.

 

LOL Well, I guess it wasn't me...I'm not on a Dyna. But, I've been known to have even some crotch rockets to get over for me while lane sharing.

BTW, call it "lane sharing", especially if you are trying to explain to a cop what you were doing. Don't ask why I know. LOL

 

Well, I guess from reading about your issues that I wouldn't call it an upgrade. Harley is selling the Agitator wheels with an 18" rear and I doubt they wobble at speed. There has to be something else at play here and maybe the combo of 21" in the front is the culprit or the 18" wheel you had on was defective.

 

I have the 21/18 combo with 200 tire and I get the wobble too. I run metzlers with renegade wheels. I would change to a 17 if I could afford it. The kicker is I originally ordered the 17 but the HD dealer ordered 18 instead and me being impatient took it with a little prodding. Wish I would have been more patient now