While poking about on my 1985 K100RS today I discovered the throttle actuating arm fouls the fuel hose that connects the fuel tank to the fuel pump. This hose is not OEM hose, but rather one I bought at the local auto parts store; that is to say, it is not molded to conform to the twists and turns in that tight engine area. When the throttle is wide open, the screw on the arm strikes the fuel hose. The hose presently passes between the throttle bodies and I can't see any obvious alternate pathway. Is the OEM hose super thin or... what?
Given the present situation on my bike, the throttle could become hung up on the hose and sometime in the future could also puncture the hose ... god forbid!
Can someone post a photo of that area of the engine so I can see the proper path of this fuel hose?

hey mate ! the fuel return line usually travels along the inside of the throttle bodies towards the radiator ...then routes through near the top then to the petcock for the return line .....the high presure feed side is normally a straight section from the outlet of the tank straight to the fuel rail ..
the return line at the rear end of the fuel rail goes under the throttle bodies towards the rear and then to the fuel presure regulator on the inside section of the throttle bodies ....best way to get at it is from the right hand side ....remove the air filter box etc
there are many types of fuel hose ...but for unleaded fuel externally look for sae30r9 or (30r10 for internal to tank useage).... this type of fuel hose has a lower pourousness and doesnt let the smaller fuel vapours found in unleaded and the all too common ethanol products escape to the air

a good web of cord built into the feed lines right up to the presure regulator is recommended
hope that helps some

think ive got some pics around here somewhere ....hang on



you can see the thicker than usual pipe at the front of the fuel rail (covered with airconditioning insulation ) and the outlet to fuel presure regulator at the rear end ...cant find a pic of the rear side at the moment

but i think on one of old goats restoration pages there is a good look at what he did with insulation and routing of the hoses

The fuel pump is inside the tank but I think the line you refer to comes from the front one of the two lines on the tank on the front left.
That hose is supposed to go from the front connector round the front of the #1 throttle body and then back to the fuel pressure regulator which is what I think you have mistaken for the pump.
The other connector (the rearward one) goes directly down to the front end of the fuel injector rail.
You may find that the hose was routed that way to make removing the tank a bit easier.

You are correct. I misspoke when I said the hose from the fuel tank to the pump. I meant the regulator. It was not at all clear that there exists a path in front of the first throttle body, but I'll pull the parts off and try again. Man, I do hate working on this bike! There is such a limited amount of space, and that foam insulation... I can never, ever fit it back in place.
Thanks for the info to get me back on track with my brick. Despite my wrenching frustrations, she's a nice bike to ride. .. sure puts a smile on my face.

I think I got it sorted properly. Thanks for the good counsel.