BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

I am considering putting a GPS on my R1200R. Has anyone installed the new Nav. IV on their bike? If so does it block visibility of instruments?

Over what do you think?

Best regards,

xcell1600 wrote:I am considering putting a GPS on my R1200R. Has anyone installed the new Nav. IV on their bike? If so does it block visibility of instruments?

Over what do you think?

Best regards,

I like it.

Thank you for your response. Do you have any difficulty seeing the instruments?

xcell1600 wrote:Do you have any difficulty seeing the instruments?

Not at all, but the cradle does obscure the bottom hemisphere of the rev counter. It's not a problem, as I usually shift by ear. If the cradle obscured the speedometer, that'd be a problem. Our bikes are deceptively fast.

Or you could just by it direct from Garmin (Yes you won't get the buttons on the side but it will be cheaper) and use the extra money for a lockable mount like I did from touratech. I can see all the instruments and even if you couldn't see the speed you can use the speed the GPS is giving you as it's more accurate!

Dave

dderrig wrote:... and even if you couldn't see the speed you can use the speed the GPS is giving you as it's more accurate!

+1 on the GPS being more accurate!

I have had 2 different GPS's on my R12R and both indicate 5 mph slower then factory speedo at around 65 mph. I just figure the factory speedo is indicating 5 mph faster to keep you safely under the limit? Or maybe trying to convince you of a faster top end speed than is true??
I guess it would be safe to say "YSMV" (your speed may vary)

Coyote Crazy wrote:I have had 2 different GPS's on my R12R and both indicate 5 mph slower then factory speedo at around 65 mph. I just figure the factory speedo is indicating 5 mph faster to keep you safely under the limit? Or maybe trying to convince you of a faster top end speed than is true??

I've always wondered about that. Speedometer heads used to be notoriously inaccurate, but now that they're stepper motors driven by a digital signal they should be right on. Maybe the calibration is set up based on an unloaded tire, and, because the tire compresses under load, the wheel actually rotates faster than the unloaded radius would suggest?

The reason BMW speedos read fast has been discussed on both moto and car lists for at least 15 years or so now.

It's intention. German law forbids having a speedo read slow - so BMW adds a fudge factor of about 5% + 5MPH to your speed (at 50 real MPH - the speedo will read about 57MPH, at 100MPH it will read close to 110MPH.) There is even a Service Info Bulletin (SIB) out floating around from BMW for service managers to explain this to owners.

What's surprising - as inaccurate as the speed readout is - if you do an instantanious speed check (reset you avg speed counter - and see what it reads just as it comes alive again) - it will be very close to your GPS speed (error within a few percent - probably from tire wear), and the odometer is also accurate to within about 2% (I've checked it via the trip-log feature on my GPS quite a few times.)

YMMV - and in this case - it does.

deilenberger wrote:It's intention. German law forbids having a speedo read slow - so BMW adds a fudge factor of about 5% + 5MPH to your speed (at 50 real MPH - the speedo will read about 57MPH, at 100MPH it will read close to 110MPH.) There is even a Service Info Bulletin (SIB) out floating around from BMW for service managers to explain this to owners.

Don, thanks for the explanation. To be truthful it never really bothered me, if for some reason I did not have my GPS mounted, I always just subtract the 5 mph at around 65 mph from the factory speedo reading and felt comfortable. Now, I must admit it is nice to know the reason behind it. I like to look at life as a learning experience and now I have learned the reason for something I just accepted. Now every time I am cruising along and noting the 5 mph differance I can just smile and know the reason why!!