I'm Jess from Denton, TX. I recently purchased a 1986 BMW K100RS that needs some repair. For the most part the bike is ready to get on the road and had been frequently run until recently. One of the fuel injectors defaulted and caught fire on the previous owner's watch. The fire damage was minimal, he luckily had an extinguisher nearby, but the throttle seems to have burnt up as well. I'm not sure if the throttle is related to the fire or not, but it is useless right now as well and the previous owner mentioned it happening at the same time as the burnt up injector. I think I have determined that the cable is still intact and good, but it looks like I will have to rebuild the throttle/fuel rail above the injectors because it is not pulling the throttle properly. By the way, what an interesting throttle cable or chain mechanism I guess really. I haven't seen anything like it in my experiences.

This is my first BMW bike. In fact this is my first bike to own that is water cooled and with fuel injection systems, etc. Everything I have worked on has been pre-1981 up to this point. I started on two-stroke dirt bikes. I have a couple of 68 Yamaha DT1s and a 74 Yamaha DT360. My first motorcycle was a 1981 Yamaha Virago 750. I currently ride a 1991 Yamaha Virago 750 and my favorite to date is my 1979 Suzuki GS550 Cafe racer build. 

The BMW will present some new challenges for me and I am excited about working on such a great bike. I am excited also to have a quality forum as a resource. Thank you in advance for sharing your knowledge and ideas with me! 

How do you share pictures within the post?




Jess

Welcome Jess , take a look at the link below

https://www.k100-forum.com/t998-posting-pictures-and-movies

we all like pictures here

John R

Thanks, John! 

G'day Jess , glad you worked out the posting thing , your bike looks like it might be an RT judging by the handlebars and the line across the rear quarter of the crankcase cover ( caused by the fairing rubbing ) , the round headlight is throwing me , what are your plans with it ?

John R

possibly the internal liner of the accelerator cable has melted ?

welcome aboard

have fun with the rebuild

Hi Jess and welcome too.

I agree with the RT comment, the bars and fairing rubbing line on the right hand side engine case are a give away. If you are replacing cables or front brake pipe from the handlebar reservoir you probably should be buying RT/LT cables and not RS as they are shorter.

Its quite possible it started life as RT and then got fairing damage. Its not unusual and not something to be alarmed about, just some owners then turn them naked rather than go replacing the fairing. If you post up the VIN number it can be checked as to that the original was. Your frame number will also say if it is RS RT or LT. See the plates on the left side beside the battery.....

When you are in there replace the fuel lines to the injector rail. Cheap but they perish and go hard and crack easily if you are doing any work. They are all pressurised so a leak can be serious if it happens. Get the BMW pipe, not expensive. Make them slightly longer and you can access the electrical box and the coolant top up without disconnecting them. Check the crank case ventilation in behind the throttle cable/manifold connection, its soft and rubbery and can crack easily and cause bad running.

The fuel line at the front of your injector rail....mine has heat insulation around it to protect it from the radiator hot air...... 

You putting a heat shield back on the muffler?

Hi Jess!

welcome to the forum   If you ride up to Tulsa give us a shout!

Dale.