WRIST: Marc Cook
MSRP (2016): $19,760 (as tested)
MILES: 12,710
MPG: 38
MODS: New Michelin Pilot Road 4 tires
Because my 2016 BMW S1000XR is getting ridden so much—by me and by the rest of the staff looking for a good time—the 12,000-mile maintenance was due four months after the 6K. This time I leveraged the maintenance to visit some friends at Mamba Motorsports (mambamotorsports.com), a BMW dealer in northern Los Angeles County. The bike went in with a few wants, including the core maintenance, a check on the weeping right fork seal, and my heads-up to check the brake pads; when I’d changed the last set of tires, the front pads looked a little thin. Not enough to change them there and then, but enough to plant the seed that these could be fast-wearing items—along with the recollection that the XR had spent a full day at the track.
The final bill was a little heady, I have to admit: $977. Breaking it down, then: $342 is for the basic 12K maintenance, including 1.5 hours of labor, $58 worth of oil, an $18 oil filter, and a $50 air filter element. Brake pads boosted the price by $316 for all three sets. I’ll keep an eye on them from now on but I suspect that this is the price you pay for incredibly strong brakes with superb feedback. That said, I’m tempted to try some aftermarket options.
Mamba took care of the leaking fork tube under warranty by replacing the seals, and I don’t know what the labor charge would be, but the parts alone would be almost $90. I did get thrown a curve on this maintenance, and it happened even before I’d left the building. Mamba’s Service Manager, Jeff Granados, found me and gave me the bad news about the Dunlop Q3s on the bike. The rear had picked three small nails. A real shame, since I had managed to get the Dunlops to 2,680 miles with plenty of life left. In fact, I’m pretty sure I could have gotten this set to 4,000 miles, which is superb for a very sticky, compliant tire. Not, however, a fantastic wet-weather tire, which is why I had Mamba spoon on a set of Michelin Pilot Road 4 (motorcycle.michelinman.com; $570/set MSRP).
I was out of town when the bike was finished, so Associate Editor Julia LaPalme picked it up for me, returning the R1200GS that Mamba had lent me while the XR was being serviced. (That was an interesting comparison. I’d forgotten just how relentlessly competent the GS is, beautifully composed and un-ruffleable, if that’s even a word.) Immediately after, Mr. MC Garage himself, Ari Henning, borrowed the bike for a weekend blast. This is important because neither of them reported anything strange with the bike.
I was reunited with the XR for only a few moments when I discovered a drywall screw in the almost-new rear tire. Really? Really?? I had our shop guy install an internal patch—yes, in direct contravention of Michelin’s recommendations, sue me—while I waited for a replacement tire to arrive. (Honestly, if it were my own bike, I would probably continue to run the internal patch, but this is an official test of the tire and I want to give Michelin a fair shake.)
The next time I rode the bike it had a nasty vibration, shaking through the bars at any speed above 70 or 75 mph. When I got home, I double-checked that both wheels had balance weights (ensuring that they hadn’t flown off) and did a quick check to make sure the wheels weren’t damaged in any way. All looked good. After a few more miles of this terrible vibration, which was most evident through the handlebars, I started checking the front end. Finding the front balance slightly off, I rebalanced it and rode; a tiny bit better but not cured. I then mounted a known-good front tire; no change. I then rode the XR assigned to Sport Rider magazine, which was really smooth. Enlisting the help of SR’s Bradley Adams, we swapped bikes. He came back the next day saying, “Yeah, that’s a really bad vibration but what’s up with the fork?”
Preternaturally sensitive, Bradley felt like the fork wasn’t using all its travel. Testing the fork stroke on the two bikes side by side in the parking lot did reveal mine stopping early in the travel. I wasn’t sure that this symptom had anything to do with the vibration but it would have to be fixed. Mamba, for its part, said bring it in and we’ll get to the bottom of it, but I’m excessively curious. So I disassembled the right fork leg to discover it had been over-filled with oil. Draining it and refilling to the correct level, 90mm from the top of the tube with 7.5 weight oil, would fix that problem. Oh, in case you’re curious, the right fork leg on the XR has a spring and a cartridge that feels like it has only compression damping; it either has no or very little rebound effect. Most of the damping changes come through the left leg, which has the electronic valves.
Fixing the fork did nothing for the vibration, which reappeared the next time I hit the freeway. Luck was with me, though. It just happened that it was late in the day and the setting sun was just off my left. I don’t know why I did, but I looked over to my right at the shadow of the bike. Clear as could be was the rear wheel bouncing up and down to the same tune as the vibration through the handgrips. Well, there’s your problem.
A few minutes after congratulating myself for finding the problem, I felt incredibly stupid for forgetting a very basic thing: Actions at one end of the bike can strongly influence things at the other end. Worse, I’d had a similar thing happen on my Suzuki GSX-R750 many years ago. Maybe I was sharper then, but I checked both ends of the bike and found the problem quickly. Also, the nature of the BMW, firmly sprung, stiff chassis, tall/wide handlebars all conspired to make the shaking rear tire feel like it was something at the front.
Part of the problem was forgetting this interaction but part was making a bad assumption. I knew the rear tire had been patched and our guy had rebalanced the wheel when he was done. His work is uniformly good, so I’d dismissed the rear tire’s influence because he just doesn’t make many mistakes. It had to be something else. I made the classic mistake of focusing on one piece and not stepping far enough back to consider all the options. Lesson learned. Again.
Obviously, re-balancing the wheel fixed the immediate symptoms while I wait for a replacement Michelin to arrive. I can say that I’ve had a couple of opportunities to ride the XR in wet conditions, and I think I’ll be glad to have the PR4s on the bike through the winter. (Although as I write this in early February, we’re looking at a dry week with temperatures in the high 70s and low 80s…what the hell?) The PR4s get warm quickly in cold weather, obviously move a lot of water out of the contact patch, and feel really confidence inspiring when the pavement is slick. I also appreciate that their profiles have retained the XR’s sharp steering. So far, the XR and the Pilot Road 4s seem like a happy pairing.
One last thing: Suburban Machinery sent me a set of bar-end weights for use with the hand guards (suburban-machinery.com; $84). These weigh 11 ounces each, 2 ounces more than the HVMP bar-ends I’d been using. Honestly, I can’t tell the difference in vibration between the two, but each is far better than the lightweight original bar end. I was able to confirm the benefits of the heavier bar ends while borrowing SR’s stock XR; the difference is truly amazing. Some bikes take hundreds or thousands of dollars to fix the most annoying “features,” so it makes me almost giddy to say the XR’s major shortfall can be dealt with for $80.
Previously In The MC Garage:
Overcoming the early adopter blues.
Long-Term BMW Motorcycles S1000XR Gets New Michelin Pilot Road 4 Tires
Keine Kommentare:
Kommentar veröffentlichen