The widest 17" is 130, it was actually a bit too wide for the XL it wasn't much narrower than the Karoo that comes on the TE (which actually rubs the muffler).
The rear rim on a TE is 2.5" wide but the rear rim on the SM is 4.25". Stock tire size on the rear SM rim is a 150. Harabec is looking for dirt-worthy tires for his SM rims so I'm thinking the 130 would be too narrow. At least, I didn't want to put that narrow of a tire on mine. The 120 on the front worked OK, though. WoodsChick
Not so easy. The SM forks have larger size holes for the caliper bolts..you need to retap the TE caliper to 10mm. The SM forks are wider necesitating custom caliper and wheel spacers. The 21" wheel will hit and destroy the fender on the SM if it does not flip you over the bars. What I did was lace a 19 x2.50 front rim to a TE hub and retaped the disk mounting bolts to 8mm. I run the SM brake disk. I run TKC80s on the front and rear. The 19" front required a trim of the SM fender to clear on bottoming.
From Buccanan's, that guy in Calif that does those custom wheels... I laced a 2.50 x 17 rim to the rear too.
I did the 21/18 conversion on my 08 SM610 and your info is not totally correct. The TE/SM forks both have the same 10mm holes in the forks. The TE just uses caliper bushings to make up the space difference for the 8mm bolt and positions the caliper in the correct spot. All you have to do is order the bushings, get a TE brake assy, wheel, and spacer and it is a total bolt on affair. The only problem was the TE master cylinder uses a different brake light swith so the SM wiring does not plug right in. I had to make an adapter for that. The fender does rub and will eventually break. I got a used SM fender and a aftermarket TE fender from Dan at motoxotica, cut them in half and bolted them together to make a hybred fender that worked perfectly. Which looks just like the new TE630 fender by the way. The cool thing about using a 19" rim is you can keep the SM brakes on but with 21" wheel the caliper hits the spokes. Cool thing with the TE brakes, all I have to do to switch is unbolt the master cylinder, hose and caliper and the whole assy comes right of without cracking a brake line. Slide the SM stuff on and away I go. But in truth, I hate th TE brakes. I got used to the SM brakes. Even with 17's and knobbies in the dirt the SM brakes were awsome...I see Bills Husky said to just use the SM master cylinder, I wonder if I could get a little better braking power that way. Hummm... Frank 08 Husky610
There are reasonable highway tire options even in a 21/18 configuration. As far as I am concerned 90% of the reason to go from TE to SM wheels is to get the big brake. A TE front brake isnt very confidence inspiring if it has already hauled you down from speed anytime in the last 10 minutes. My inclination on the street is to primarily use the front brake, but on my TE610 I find myself using the rear quite a lot on pavement.
You can even use the spacer from the SM wheel, I found that out today after thinking I was gonna have to order a separate spacer for awhile.
