CMGR1100RT
New member
2011 R1200RT previously fitted with Eastern Beaver Power Center 8 fuse box. I selected the Hella Sharptones horns (one high, one low) to replace the OEM horn after watching comparison videos on-line. On my previous 2001 R1100RT I replaced the OEM horn with FIAMM Highway Blasters and loved the rich, loud sound; however, the Hellas are louder. In fact, now that the installation is complete – I can attest that the Hella Sharptones are extremely loud and exactly what I was looking for.
Materials
Hella H31000001 114dB 12V Universal Sharptone Panther Dual Horn Kit (Yellow) $56
OPT7 Off Road LED LIGHT Bar On-Off Power Switch 40 Amp Relay Wiring Harness (Dual Light Bar Harness) – Double Connect 380W $25
83 30 0 402 344 BMW Genuine Repair plug 2-pin $16
TechFlex Flexo F6 General Purpose 1/2-inch Braided Cable Sleeve, Black $ 9
8 87480 03448 6 574 405 Everbilt Cap Screw 8MM X 40MM $ 1
8 87480 15058 2 595 724 Everbilt Nylon Spacer 1” Long $ 1
8 87480 03448 6 595 089 Everbilt Lock Nut M8-1.25MM Nylon Insert $ 1
Various washers, .25” female wire terminal connectors, plastic sheaths, wire ties, shrink wrap, dielectric grease
The Hellas come with a 30 amp relay, but no wiring harness. I did not use the relay supplied with the horns as the Opt7 wiring harness comes with its own relay. Manufacturer’s website indicates the horns draw 66 watts. I’m not sure whether that is per horn or for the pair. 66 watts ÷ 12 volts = 5.5 amps. I decided to use a relay in my installation. An alternative to Sharptones is the Hella Supertones. They are not as loud, have a different tone and are larger in size. Review on-line comparisons where you can see and hear them, and make your own decision. All three mentioned above are great choices.
Not trusting my ability to make a professional-looking wiring harness, I purchased the OPT7 wiring harness after exhaustive on-line research. It came with a relay, but no wiring instructions. It utilizes all 14 awg wire and is very high quality. It is designed for off road LED lighting, but works well for bypassing CanBus for motorcycle horns as well. To keep my OEM wiring intact, I purchased the BMW repair plug which plugs into the horn connector wire once it is unplugged from the OEM horn. No OEM wiring was modified.
I mounted the Hella relay underneath and just behind the front seat with a wire tie. The wiring runs up the clutch side of the bike to the horn positions. The length of the wiring in the wiring harness is much longer than required.
I installed the low tone horn where the OEM horn was. I used the included Hella mounting bracket, the OEM mounting bracket and the miscellaneous Everbilt hardware purchased at Home Depot. Since the Hellas are larger than OEM, this setup allowed the Hella to be positioned forward and left of the OEM position to avoid contacting the front brake line or shock absorber.
I installed the high tone horn on the OEM mounting area for the second OEM horn (front clutch side near oil cooler.) The OEM horn was missing which I believe is normal, but the mounting area is a good fit for the second Hella. I positioned both horns with their terminals positioned upwards, so rain water would drain from under the plastic wire connector sheaths.
Wiring:
Red to battery wire of Opt7 Wiring Harness to PC8 Fuse box - switched power (or battery)
Black to battery of Opt7 Wiring Harness to PC8 Fuse box - ground (or battery)
Red to lights of Opt7 Wiring Harness to High tone horn (unmarked terminal)
Black to lights of Opt7 Wiring Harness to High tone horn (terminal marked with green dot)
Red to lights of Opt7 Wiring Harness to Low tone horn (unmarked terminal)
Black to lights of Opt7 Wiring Harness to Low tone horn (terminal marked with green dot)
White to light switch of Opt7 Wiring Harness - Only required for separate light switch. Cut and insulate this wire.
Blue to light switch of Opt7 Wiring Harness to BMW Repair Plug - wire marked "02"
Black to light switch of Opt7 Wiring Harness - Only required for separate light switch. Cut and insulate this wire.
Wire marked "01" of BMW Repair Plug to Low tone horn (terminal marked with green dot)
Note: the Opt7 relay is designed to operate off road LED lighting. So, it is has a switch to turn the lights on and off. This switch is obviously unnecessary for the horn installation as the OEM horn button is used to activate the horn. So, two of the three switch wires are unnecessary for the horn installation as the OEM horn button, OEM wiring and BMW repair plug serve this purpose. I tested these three wires and concluded, the blue wire is to feed the power from (in our case) the OEM horn button to activate the relay. The black wire is to light the Off Road lighting switch and is unnecessary. The white wire carries power to the switch that flows back to the relay via the blue wire when closed by the switch. So, the white wire is unnecessary. You may want to check these wires with your multimeter before cutting any wires as it is possible there could be manufacturing inconsistencies in the wire coloring, and cutting the wrong wire and having to repair/splice it would defeat the advantages of purchasing the wiring harness in the first place. An alternative may be to remove the unnecessary wires at the relay connection, but I did not explore that option.
This wiring setup would work well for Hella Sharptones, Hella Supertones and FIAMM Highway Blasters, where a two horn configuration is utilized. Opt7 makes a single connection relay that can be used for single horn installations. The Hella Sharptones are piercingly loud and should get the attention I’m looking for.
Materials
Hella H31000001 114dB 12V Universal Sharptone Panther Dual Horn Kit (Yellow) $56
OPT7 Off Road LED LIGHT Bar On-Off Power Switch 40 Amp Relay Wiring Harness (Dual Light Bar Harness) – Double Connect 380W $25
83 30 0 402 344 BMW Genuine Repair plug 2-pin $16
TechFlex Flexo F6 General Purpose 1/2-inch Braided Cable Sleeve, Black $ 9
8 87480 03448 6 574 405 Everbilt Cap Screw 8MM X 40MM $ 1
8 87480 15058 2 595 724 Everbilt Nylon Spacer 1” Long $ 1
8 87480 03448 6 595 089 Everbilt Lock Nut M8-1.25MM Nylon Insert $ 1
Various washers, .25” female wire terminal connectors, plastic sheaths, wire ties, shrink wrap, dielectric grease
The Hellas come with a 30 amp relay, but no wiring harness. I did not use the relay supplied with the horns as the Opt7 wiring harness comes with its own relay. Manufacturer’s website indicates the horns draw 66 watts. I’m not sure whether that is per horn or for the pair. 66 watts ÷ 12 volts = 5.5 amps. I decided to use a relay in my installation. An alternative to Sharptones is the Hella Supertones. They are not as loud, have a different tone and are larger in size. Review on-line comparisons where you can see and hear them, and make your own decision. All three mentioned above are great choices.
Not trusting my ability to make a professional-looking wiring harness, I purchased the OPT7 wiring harness after exhaustive on-line research. It came with a relay, but no wiring instructions. It utilizes all 14 awg wire and is very high quality. It is designed for off road LED lighting, but works well for bypassing CanBus for motorcycle horns as well. To keep my OEM wiring intact, I purchased the BMW repair plug which plugs into the horn connector wire once it is unplugged from the OEM horn. No OEM wiring was modified.
I mounted the Hella relay underneath and just behind the front seat with a wire tie. The wiring runs up the clutch side of the bike to the horn positions. The length of the wiring in the wiring harness is much longer than required.
I installed the low tone horn where the OEM horn was. I used the included Hella mounting bracket, the OEM mounting bracket and the miscellaneous Everbilt hardware purchased at Home Depot. Since the Hellas are larger than OEM, this setup allowed the Hella to be positioned forward and left of the OEM position to avoid contacting the front brake line or shock absorber.
I installed the high tone horn on the OEM mounting area for the second OEM horn (front clutch side near oil cooler.) The OEM horn was missing which I believe is normal, but the mounting area is a good fit for the second Hella. I positioned both horns with their terminals positioned upwards, so rain water would drain from under the plastic wire connector sheaths.
Wiring:
Red to battery wire of Opt7 Wiring Harness to PC8 Fuse box - switched power (or battery)
Black to battery of Opt7 Wiring Harness to PC8 Fuse box - ground (or battery)
Red to lights of Opt7 Wiring Harness to High tone horn (unmarked terminal)
Black to lights of Opt7 Wiring Harness to High tone horn (terminal marked with green dot)
Red to lights of Opt7 Wiring Harness to Low tone horn (unmarked terminal)
Black to lights of Opt7 Wiring Harness to Low tone horn (terminal marked with green dot)
White to light switch of Opt7 Wiring Harness - Only required for separate light switch. Cut and insulate this wire.
Blue to light switch of Opt7 Wiring Harness to BMW Repair Plug - wire marked "02"
Black to light switch of Opt7 Wiring Harness - Only required for separate light switch. Cut and insulate this wire.
Wire marked "01" of BMW Repair Plug to Low tone horn (terminal marked with green dot)
Note: the Opt7 relay is designed to operate off road LED lighting. So, it is has a switch to turn the lights on and off. This switch is obviously unnecessary for the horn installation as the OEM horn button is used to activate the horn. So, two of the three switch wires are unnecessary for the horn installation as the OEM horn button, OEM wiring and BMW repair plug serve this purpose. I tested these three wires and concluded, the blue wire is to feed the power from (in our case) the OEM horn button to activate the relay. The black wire is to light the Off Road lighting switch and is unnecessary. The white wire carries power to the switch that flows back to the relay via the blue wire when closed by the switch. So, the white wire is unnecessary. You may want to check these wires with your multimeter before cutting any wires as it is possible there could be manufacturing inconsistencies in the wire coloring, and cutting the wrong wire and having to repair/splice it would defeat the advantages of purchasing the wiring harness in the first place. An alternative may be to remove the unnecessary wires at the relay connection, but I did not explore that option.
This wiring setup would work well for Hella Sharptones, Hella Supertones and FIAMM Highway Blasters, where a two horn configuration is utilized. Opt7 makes a single connection relay that can be used for single horn installations. The Hella Sharptones are piercingly loud and should get the attention I’m looking for.
