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This is the description of how to do it for an R1100RT, but GS should be the same except for fusebox access.
Myke
<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w

oNotOptimizeForBrowser/> </w:WordDocument> </xml><![endif]--> [FONT="]In order to fit a relay to enable bike engine to Start & stay running on sidestand, but cut out if the bike is put into gear, the following modifications are needed:[/FONT]
[FONT="]A Siemens relay, Single pole normally open. (526)-V23134-K52-X181 BMW 6136 1389 105 [/FONT]
[FONT="]( From Breakers, get a yellow “Load relief” relay, base & wiring connectors.)[/FONT]
[FONT="]This relay has a diode in series with terminal 87b, and a consequence, cannot back feed anything else.[/FONT]
[FONT="]Start with bike on main stand, remove seat & rear wheel.[/FONT]
[FONT="]The fusebox & relay plastic box is split into two halves, secured together by 4 self tapping screws installed from above. Only 2 are readily accessable, so remove thee, take out the 2 off 6mm screws ( 1 each side) & press fusebox assembly down slightly. This will give angled access to the other 2 screws. Remove these, & the base of the fusebox assembly bottom cover may be wriggled downwards and off.[/FONT]
[FONT="]All neccessary wiring is now accessable.[/FONT]
[FONT="]Modifications as follows:[/FONT]
[FONT="]Relay & mounting block fit into unused relay base area in under seat relay box.[/FONT]
[FONT="]The relay base is installed from underneath, pressing it up onto the existing spare bracket.[/FONT]
[FONT="]On drawing, the following information is useful:[/FONT]
[FONT="]30 = Battery 12v, always at 12v. (Usually Red Wire)[/FONT]
[FONT="]31 = 0v. (Usually Brown Wire)[/FONT]
[FONT="]15 = 12v on with Ignition (Usually Green/White Wire)[/FONT]
[FONT="]Before installing the relay base unit, the following 4 “tails” are left hanging out of the relay base. [/FONT]
[FONT="]The tails are approx. 200mm long and may be trimmed later as required. [/FONT]
[FONT="]From terminal 30 : Green/White. (15)[/FONT]
[FONT="]From Terminal 85 : Green/black wire.[/FONT]
[FONT="]From Terminal 86b: Brown/Black wire.[/FONT]
[FONT="]From Terminal 87 : Green/Red.[/FONT]
[FONT="]Relay to be fitted as follows:[/FONT]
[FONT="]Coil Connections: [/FONT]
[FONT="]85 Link on to the Green/Black wire going to Fuse 1.[/FONT]
[FONT="]86b Link on to any of the Brown/Black wires going on to terminal 86a of the starter relay.[/FONT]
[FONT="]Contact connections.[/FONT]
[FONT="]30 Link on to the lighter of the two Green/White wires going to terminal 86 of the Motronic relay. (There are 2 Green/White wires going to this relay. Be sure to pick the smaller diameter one.) [/FONT]
[FONT="]87 (The awkward one) Link on to the Green/Red wire from the sidestand switch. (You have to push wire out through grommet to sidestand wiring connection) [/FONT]
[FONT="]Replace the original loom tywrap with a new one clipping the additional wire to the loom.[/FONT]
[FONT="]Now you have to put the base back onto the fusebox. Allow plenty of time for this operation.[/FONT]