Won't start - coil and ignition module working

[Luke_Foster]

Hey guys, I have a 1986 r65 (90K on the clock) that failed on me a few weeks back after a 100km ride.

Rode like a dream then wouldn't start the next day. Tested the battery, charged the battery, then replaced the battery. Still nothing.

Independently tested the coil on my mates '84 LS, working. Did the same with the ignition module and again it's working.

Tried pulling the spark plugs and testing for spark, neither side spark at all.

Any suggestions on where to next?

Cheers,

Luke.

[bruce_launceston]

Check the kill switch?

[Luke_Foster]

I've just been reading those posts about the kill switch. Won't get the chance to check until next week, I'm hoping that's all it is...

[georgesgiralt]

I hope it's the kill switch because if it doesn't, its the bean can ....
You'll have to find a replacement Hall sensor and change it.

[Luke_Foster]

Thanks Georges, I have found a few good documents showing how to change the hall sensor and I have found replacements at Jaycar for $19 and a whole you system at Motorrad Elektrik for $325. Hopefully it's just the kill switch though!

If it's not, is it worth trying to re-install the hall sensor myself (looks fiddly) or would people recommend just getting an upgrade? I wouldn't mind having a play myself (just to learn more) but I don't want to F*$k it  

[nhmaf]

There are some instructions on the internet somewhere on replacing the hall effect sensor in the beancan.   There are apparently (2) subspecies/subversions of the beancan with the hall effect sensor - one which has more rivets that need to be drilled out and replaced with screws with threadlocking compound (not permanent though).   I will try to post links if I can re-find it.  

It is a fiddly operation, but we've had some members succeed with it who can provide first hand guidance - usually the hard part (these days) is finding a suitable replacement hall sensor in stock.

Before I dove into the bean can though - just to be certain you've eliminated all the "easy" things first - I'd also try a new set of plugs and plug wires (or at least 1 new one of each - I always carry a spare plug and cable in my on-bike kit..

[georgesgiralt]

Hello !
Google for the ignition timing tool (a box from BMW to replace the bulb one used when we had points). This "device" (actually very simple) lights a LED when the ignition point is reached.
If you use this device while turning the bean can shaft and the LED lights your Hall effect sensor is working.
(I made such a device and carried it to a junk yard to test the second hand bean can they tried to sell me. I can't find it now...)
IRC it needs a 9V battery, a couple of resistors, a LED and either the mating connector (3 prongs) or test contact from an electronic shop.

[Luke_Foster]

Thanks guys, I'm going to try new plugs and wires first, just in case they were the problem, thought it strange that both should go at the same time though...but you never know.

Seen a few timing tools on ebay for approx. $30 so I might try one of those.

I will update next week when I get to the bike.

[tvrla]

There is a test procedure to determine what exactly is the problem. Throwing parts at it can get expensive and still not cure the problem. It's much better practice to pinpoint the issue with troubleshooting, then replace the offending part.

Since your friend has a similar bike, you could substitute his bean can as a test - and I'm betting that's the problem. The Hall Sensor.

[Luke_Foster]

Update:

Finally was able to take a look at the bike (been interstate for work and recently moved), followed the steps outlined in:

http://www.deathstar.org/~flash/ig_trig.html

to test whether the problem was likely to be the bean can. Followed the steps and got a good spark, so looks like it is the bean can.

Now for the fun bit...