I have an 05 Sportster which I really love. It just passed 10k miles yesterday on the way to work

Aside from the handlebars being a bit to short for me, my only real issue with the bike is the ridiculously thin front tire. Any pavement patches or cracks going the same direction as me I really feel.

This brings me to my question: What's the widest tire you can put on a stock 05 Sportster? I don't mind replacing the wheel too if needed. If anyone has any other ideas I'm open to them as well.

 

Why not get the best front tire, instead of the fattest?

Pirelli Night Dragons. Front and rear, you'll be amazed. All those issues will go away. If you have Dunlops, you deserve better.

John

 

"ridiculously thin front tire"...can I assume you have 21" wheel with the stock size MH90 tire?

If so, you can put a 90/90-21 (MH90=80/90) on that rim or if you move to a 19" sportster wheel, you can use a 100/90-19 or 110/90-19

 

The problem of "following" grooves, cracks, bridge grates, etc. is more a tire tread design issue than tire size. Get rid of the stock Dunlop tire and switch to a Metzeler 880, Michelin Commander, Avon, etc. that doesn't have a tread cut around the center of the tire.

What you don't want (Dunlop)



What you do want (Metzeler)




But switching to a 19" wheel with one of the better 100/90-19 tires will give you noticeably better handling and tire mileage than using the 21" wheel.

 

I agree, my 06 with 21" was getting really spooky, front tire was old and worn.
Put a new front tire on and I now have a new bike.
I installed the "Newly Designed Dunlop" ...and like Charley says it doesn't have the
center tread, the NEW Dunlop looks like Metzeler and the bike handles completely
different.
Thanks to Charley's post I now know why.

 

Thanks for the feedback all. There was also the issue of me fitting on a Sportster. I'm 6'6" and 235lbs. I could ride it easily enough but I was using it as my daily driver and it wasn't exactly comfortable. This weekend I purchased a 2006 Road King, it fits me much better. Night and day difference riding the RK vs the Sportster.

 

Noticed all the Dunlops D401, D402, D404, K591 , including z Michelin Scorcher
made for H-D , all have that center groove, probably good in rain.

Does the 110/90/19 front require a 2.5" width rim or is 2.15" width acceptable.

 

Lots of good info here
http://hdwheels.com/Product.htm

2.15 is acceptable

 

Attempting to answer the OP question rather than steer to a non center groove tire.
Inside width between sliders on the 05 XL should be 5,0" with 6-15/16" center to center tube width.
It appears that a Dunlop D220 street/sport-touring, 120/70ZR18, overall width = 4.76" is the widest tire that will fit between the sliders..,
based on specifications from the Dunlop big book catalog.
The Dunlop D220 , 120/70ZR17 overall width = 4.72, but is 1" smaller in overall diameter.
If a bias tire is desired, The Dunlop D404 cruiser tire with the continuous staggered center groove, 120/90-18 is 4.64" overall width.

The Sportster XR 1200 came stock with a three spoke. , sport style, 3.5" X 18" cast front wheel produced from 2009 to 2011.
The XR 1200 came stock with the a 120/70--18 radial front tire, so if an XR1200 front cast wheel can be located, the whole thing bolts right up to the 05,
except maybe for some 52mm x 3/4" bore beaings.
Do not know front axle diameter for the XR1200.
Another option is to make a laced wheel using spun aluminum 3.5" x18" rim and stock 2005-2007 aluminum center hub.

Dunlop D401 , 100/90-19 overall width = 3.95"
So going to the 18" wider tire gains 0,81" in width.
And only 0,34" less than a Dunlop D404 130/90-16 and 0,44" less than Dunlop D402 MT90B16.

The first production year for the XL 48 with the 130/90-16 front tire and 9,0" wide fork was 2011.
It is obvious that H-D dropped the XR1200 sport inspired bike and for the tough looking vintage style bike.

 

It appears you haven't taken the front fender and the fender mounts on the fork legs into account. The distance between the fender mounts on my forks is (tape measure) 4.5", and less than that with the fender installed.

And I wouldn't discount the negative effect the center groove has, staggered or not", on the bike's handling. The difference without the groove is pretty dramatic.