Installing OEM heated grips (with bar end weights)
By MT350Explorer
This is my experience - not saying it is 100% the right way but it does show some of the key steps involved. I would suggest reading it in conjunction with other posts on heated grips.

This is for fitting OEM BMW grips to a K100 16 valve with non heated grip bar end weights and non heated grip bars but with OEM grips and subsidiary loom. Much will apply to other models.

1. I took off the old left hand grip and used a metal disc in a small angle grinder to make a slot in the bar end. On the left the slot in the handlebar can be quite small as the heated grip does not rotate - so you just need room to clear the wire and contact on the outer grip end. I then drilled a hole from the top through the bar for the screws that secure the grip in place. These were threadlocked with blue Loctite when I put it all together.

2. On the throttle side you need to remove the throttle assembly - involves disconnecting the throttle cable at the throttle end - all pretty simple and intuitive, especially when you have the new part in your hand. Unfortunately no photos. On the throttle side you WILL NEED to grind away the uppermost 180 degress of the handlebar (not just a slot like the left hand side). See other posts for a diagram. This is to allow the wires contacts on the outer end of the heated grip to be clear of any obstruction as you turn the throttle.

3. The bar end weights need modifying if they do not have cut-outs. There is plenty of rrom for the wires to be inserted down the bar end tubes. I held the two parts in a vice and ground through them together. With hindsight I would not have ground the bar end tube as quite as close to the bar end as I did. In the second photo below you can see how the cut out in the bar end weight lines up with the cut out in the handlebar to allow the heated grip wire access.

4. This is how the wires run. Notice I have destroyed the rubber 'O' ring and its groove that sits half way along the bar end weight. Still works well and is solid but again - if I were doing it again I might try and keep these..

5. In the centre I drilled a single 10 mm hole. Like all the other metal cuts I made I checked for sharpo edges and then painted afterwards to inhibit rust a bit. This one I also filled with some roof and gutter seal to stop the wires chaffing. Threading the wires took me a while and like others have mentioned a bicycle gear cable worked. Even so, it too quite a while due to the right angle in the handlebars.

That's about it. Fitting the switch and subsidiary loom and connecting it all up is straightforward.