The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: suecanada on June 21, 2007, 08:41:18 PM

Title: Can't remember why a bike won't start in gear??
Post by: suecanada on June 21, 2007, 08:41:18 PM

Hi, Guys and gals...having a senior moment here...what is the problem when a bike won't start unless it is in neutral.  My riding buddy David's R1100Rt will only start if in neutral. If Clutch is pulled in and it is in gear just doesn't work anymore all of a sudden. We went over this thoroughly on our old forum but that info is lost now....remind me again what he needs to replace!

Title: Re: Can't remember why a bike won't start in gear?
Post by: Bob_Roller on June 21, 2007, 09:24:26 PM

It's the switch at the clutch lever. Follow the wires from the switch to a connector, and jumper the wires with a piece of wire, your bike should start now.

Title: Re: Can't remember why a bike won't start in gear?
Post by: Jon_P on June 21, 2007, 09:57:20 PM

i found that out when i removed it, that switch leads to ground so you may also have a bad ground or the switch is bad.

Title: Re: Can't remember why a bike won't start in gear?
Post by: billygoat on June 23, 2007, 10:48:36 PM

 Hey all,
I rember something about a bad diode (#3 DIODE  -   61311358268 $12.39 ) on the wire harness if you need to pull the clutch in to start.

Title: Re: Can't remember why a bike won't start in gear?
Post by: Justin B. on June 23, 2007, 11:10:14 PM

I would need to look at the schematic but the diode isolates the neutral switch from the clutch switch so they won't interact with each other.  I think that if the diode was to short then when you pulled in the clutch it would activate the neutral light, but it's been a long time since I looked at that circuit.  I suppose if the diode was to open then maybe either the neutral OR clutch switch might not function.  I don't know  if an oilhead uses the same circuit or not...  

Title: Re: Can't remember why a bike won't start in gear?
Post by: airhead on June 23, 2007, 11:43:16 PM

Here's the schematic, so will give an indication of the actual circuit, unlike a wiring diagram which would have to be model specific.

(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fi2.photobucket.com%2Falbums%2Fy22%2Fr65%2Fclutch_neutral.jpg&hash=ee3611c5a0dd5bc70e1746e693f07e1f6d5b1f8a)

Bill.......................;-)

Title: Re: Can't remember why a bike won't start in gear?
Post by: airhead on June 23, 2007, 11:46:41 PM

Quote

Hey all,
I rember something about a bad diode (#3 DIODE  -   61311358268 $12.39 ) on the wire harness if you need to pull the clutch in to start.

What you have shown is the harness and diode for the emergency flasher circuit, it uses a diode as well to prevent feedback to the flasher circuit when in operation.

Bill.......................;-)

Title: Re: Can't remember why a bike won't start in gear?
Post by: Justin B. on June 24, 2007, 12:08:19 AM

Looking at the diagram supplied by Bill then it would appear to me that if the diode were to open then the neutral light would work normally but the bike would not start when in neutral, unless the clutch was pulled in - the clutch switch would function properly.  If the diode was shorted then the neutral light would illuminate when the clutch was pulled in, but the circuit would otherwise operate "normally".

Now that Bill mentioned it, I think I remember the isolation diode only having one connection per end...

Title: Re: Can't remember why a bike won't start in gear?
Post by: Bob_Roller on June 24, 2007, 08:36:52 AM

That diode is located inside the starter relay I believe beginning with the '81 model year. I replaced one about 24 years ago, on my original starter relay. Mine failed with continuity in both 'directions', and every time the clutch was pulled the neutral light would come on.

Title: Re: Can't remember why a bike won't start in gear?
Post by: airhead on June 24, 2007, 09:04:17 AM

Exactly how it works Justin.

As far as the diodes location, like Bob said, from '81 the diode is incorporated in the starter relay. For the R65, from '78 - '81 it's in the wiring loom just under the relay and looks like a small tube. Before that, the other models (/6 & /7) had it mounted behind the connection/fuse board inside the headlight shell.

Bill..................;-)