The tires arrived, even though the new SIP site still says the order is awaiting fulfillment, and so I installed them on the Sprint yesterday, which would up being more work than I was expecting, with more to come.
First off, these tires are not only big, but WIDE, and that's what makes this interesting. The front tire went on almost just fine. first I had the unpleasant surprise of discovering that the lower shock buffer had twisted and was about to pop out of the mount, so first things first, I had to fix that.
Then, even with that fixed, I discovered that the wheel was rubbing just a tiny bit on the front spring, so I pull the tire off (again) and put a washer under each wheel. Not the best, but it fixed the rubbing. It doesn't seem like a lot of work, but doing all that was a lot of work.
Then on to the rear wheel. I knew that I'd have to drop the motor out of the rear shock mount, plus remove the PM Tuning pipe to get the tires swapped. But then I found that I was rubbing on the clutch cover just a tiny amount. No biggie. More washers under the wheels, and I'm good to go. Again, and this was partly due to working out of boxes right now, this was a lot more work than it needed to be because I didn't have some basics like jack stands which would have made it all much easier.
so with my 1mm spacers (aka washers) in place, rear wheel back on, shock bolt re-installed, re-attach the pipe. Which rubs. A lot. To figure out how much, I started stacking washers on the attachment bolt from the bracket to the pipe itself. eventually, I determined that I needed a good 10mm of spacers, which is a lot of washers. Then, I remembered that I had some 8mm ID aluminum tubing which I'd actually seen recently. Dig through boxes until I find it, cut two lengths and install those as spacers. This gave me decent clearance from the tire to the pipe and it's FINALLY time for a test ride, which I know is the part you've all been waiting for.
Oh, and the center stand is now too short, so I have to stick a board under it to park it. I guess it's center stand time, which will go better with the tuned pipe anyway.
The extra diameter is noticeable when you're on the bike and took a tiny bit of getting used to. In terms of ride quality, I didn't notice it being any rougher than I'm used to, but they definitely feel better cornering. That could be because I was used to my old, crappy tires, but I don't know if they ever cornered like these do, and the old tires were also K61's, so I guess I'll never really know.
On on the highway is where I noticed the biggest difference. In the past, 65 was about as fast as I'd want to ride before it started feeling dangerous. This time, I was up to 75 and it still felt good. The increased mass and diameter really helped steady the wheels at speed. About that same time, I had a minor panic attack that I was doing 75 on wheels and tires that I just installed, and started worrying that something was going to come unstuck. So I jumped off at the next exit, gave everything a quick once-over, which all looked good, then turned around and headed home.
All in all, a PITA to install, but a big difference. If you're going to switch over to bigger, wider tires like this, be ready to do some custom fitment (at least on pre-PX bikes), especially if you're running a leftie tuned pipe. If you have a box, expect to need to drop the motor out of the rear shock, but it'll be a piece of cake after that.
That's not good.
Josie approves of the new wheels
center stand is the new side stand