Running on One Cylinder! HELP!

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Kennedy

Running on One Cylinder! HELP!

Postby Kennedy » Thu Sep 29, 2016 7:29 pm

Hi everyone!
I am a very new member to this forum (I just registered this afternoon) and I've joined because I need help - I think.

I have a 1965 R50/2 that is running pretty well on one cylinder..., but won't run on two! The left cylinder is firing and the head is warm. However, the the right cylinder is cold.
I've switched out the spark plug for a new one and slightly opened up the fuel flow, from the carb by 1/2 turn, but no luck.
I know she's getting fuel and air, and I know she's not getting a spark, because I can pull off the plug-wire and nothing changes in the way the bike runs.

Where do I begin to find out what is going on? I guess it's in the electronics, but where to begin?

Thanks in advance for responding!

Mike Kennedy

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Ruralman
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Re: Running on One Cylinder! HELP!

Postby Ruralman » Thu Sep 29, 2016 7:43 pm

Hi Mike,
I'm not sufficiently educated in mechanics but this link may help you:-

http://www.snafu.org/restore/uandm_bmw_v1.pdf

Regards
Keith


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Keith Hillier
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2011 R1200RT SE MU
2006 R1200GSA
2004 K1200RS
'Live to ride - ride to live'
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bwprice100
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Re: Running on One Cylinder! HELP!

Postby bwprice100 » Thu Sep 29, 2016 8:03 pm

Hi Mike

The first question is how standard is the ignition system. Do you still have points and mechanical advance mechanism?

Brian

www.eBolt.co.uk www.ToolroomChucks.co.uk
1958 R26, (not so many bits now)
1978 R75/7, (a project bike)
1981 R80, (was a TIC)
1995 R1100RT, (speeding ticket the first day I rode it) (Sold)
http://www.eBolt.co.uk
http://www.ToolroomChucks.co.uk

Kennedy

Re: Running on One Cylinder! HELP!

Postby Kennedy » Fri Sep 30, 2016 12:57 pm

Keith, thank you for he reference on electrical systems, I bookmarked it!

Brian, the electrical system is of the old type, yes there are the old points still in the bike. Though there are some new (old) components, the bike is still operating on the old system.
My suspicions are that the points aren't operating as they should. In that I need some help!


Mike Kennedy

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bwprice100
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Re: Running on One Cylinder! HELP!

Postby bwprice100 » Fri Sep 30, 2016 1:51 pm

Brian, the electrical system is of the old type, yes there are the old points still in the bike. Though there are some new (old) components, the bike is still operating on the old system.
My suspicions are that the points aren't operating as they should. In that I need some help!

Mike Kennedy
Hi Mike

If the bike is firing on one cylinder then I would suspect the points are working reasonably well. I would suggest investigating the coil to plug circuit on the side that is not firing using the side that is firing as a reference; that is to say you can swap components, HT leads, plugs, and coil and see if the problem swaps from one side to the other. With regard to the coil it would be worth checking the winding resistance; working side to non working side.

One more thing I would ask, is what type of plug cap are you using, as these bike don't cope so well with high resistance suppressed plug caps, do you have this type fitted?

I hope this helps Brian
1958 R26, (not so many bits now)
1978 R75/7, (a project bike)
1981 R80, (was a TIC)
1995 R1100RT, (speeding ticket the first day I rode it) (Sold)
http://www.eBolt.co.uk
http://www.ToolroomChucks.co.uk

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george baker
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Re: Running on One Cylinder! HELP!

Postby george baker » Fri Sep 30, 2016 9:48 pm

Hi
With regard to the coil it would be worth checking the winding resistance; working side to non working side.
This is a good idea if you get different readings you get a clue, if the readings are the same cold, however you can not be sure the thing is OK. Or even OK Hot.

AndyMacG's coil tested OK with a meter at the weekend, but when we tested it on one of my bikes, it was dead.

George
Member 21, R100R, and an under used K75

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Galactic Greyhound
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Re: Running on One Cylinder! HELP!

Postby Galactic Greyhound » Fri Sep 30, 2016 9:57 pm

It's using a Magneto for the HT !

See the link posted by Ruralman above for details.

Note in the link, that the two HT leads in the Magneto have adjustable safety gaps to protect the Magneto HT coil - you should ascertain that these gaps are correctly set.
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" - It works!

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Re: Running on One Cylinder! HELP!

Postby bwprice100 » Fri Sep 30, 2016 10:27 pm

It's using a Magneto for the HT !

See the link posted by Ruralman above for details.

Note in the link, that the two HT leads in the Magneto have adjustable safety gaps to protect the Magneto HT coil - you should ascertain that these gaps are correctly set.
They still have a double output coil CED

https://www.realoem.com/bmw/enUS/showpa ... Id=12_0975

See item 16

Brian
1958 R26, (not so many bits now)
1978 R75/7, (a project bike)
1981 R80, (was a TIC)
1995 R1100RT, (speeding ticket the first day I rode it) (Sold)
http://www.eBolt.co.uk
http://www.ToolroomChucks.co.uk

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Galactic Greyhound
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Re: Running on One Cylinder! HELP!

Postby Galactic Greyhound » Fri Sep 30, 2016 10:55 pm

It's using a Magneto for the HT !

See the link posted by Ruralman above for details.

Note in the link, that the two HT leads in the Magneto have adjustable safety gaps to protect the Magneto HT coil - you should ascertain that these gaps are correctly set.
They still have a double output coil CED

https://www.realoem.com/bmw/enUS/showpa ... Id=12_0975

See item 16

Brian
Hi Brian,

Yes - but I am thinking that if one of the two safety gaps at the end of the coil is set too close, then the plug at that end will not fire because it will in effect be shorted out so the engine will only fire on one cylinder. :-k

e.g. imagine if one of the two safety gaps was closed up fully, then one end of the HT coil would be earthed and only the plug at the other end would spark.
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" - It works!

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bwprice100
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Re: Running on One Cylinder! HELP!

Postby bwprice100 » Sat Oct 01, 2016 12:24 pm

It's using a Magneto for the HT !

See the link posted by Ruralman above for details.

Note in the link, that the two HT leads in the Magneto have adjustable safety gaps to protect the Magneto HT coil - you should ascertain that these gaps are correctly set.
They still have a double output coil CED

https://www.realoem.com/bmw/enUS/showpa ... Id=12_0975

See item 16

Brian
Hi Brian,

Yes - but I am thinking that if one of the two safety gaps at the end of the coil is set too close, then the plug at that end will not fire because it will in effect be shorted out so the engine will only fire on one cylinder. :-k

e.g. imagine if one of the two safety gaps was closed up fully, then one end of the HT coil would be earthed and only the plug at the other end would spark.
Yes that is always a possibility CED but the ignition coils on the pre 69 bikes are a known weakness due to heat related problems and also there are a number of coils out there that are of dubious reliability.

Although the magneto gaps can be checked, there is a danger especially if adjustments are made, that a further problem could be introduced. IMHO there are simple checks that can be done on components that are known problem areas on these bikes, namely the plug caps, HT leads and the ignition coils.

Brian
1958 R26, (not so many bits now)
1978 R75/7, (a project bike)
1981 R80, (was a TIC)
1995 R1100RT, (speeding ticket the first day I rode it) (Sold)
http://www.eBolt.co.uk
http://www.ToolroomChucks.co.uk

Kennedy

Re: Running on One Cylinder! HELP!

Postby Kennedy » Sat Oct 01, 2016 12:27 pm

Thank you to all who gave time to help me solve my dilemma. I believe I have found the problem.

Yesterday I brought out a multimeter and began checking continuity between the coil (on the right side) and the plug. To make a long story short, I found the spark plug cap dead! Yep, the plug cap conducted no electricity. Absolutely nothing!
Everything else seemed to be in good order. As it turned out, I called a local bike shop (Cadre Cycles, in Blue Ash, Ohio) and they had new ones in stock. :bounce: So, I pulled out one of my other motorcycles and rode up there right away. After spending $38 I came home with two new spark plug caps and put them on the R50 right away. After some other small adjustments, and installing the new caps, the bike started right up and ran on both cylinders!

Now I can proceed to work on my lovely two-wheeler to make her run well. Oh, there's much more to be done to make that happen, so I'll be coming back here to ask for more help.
Thank you all!!

Mike Kennedy

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bwprice100
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Re: Running on One Cylinder! HELP!

Postby bwprice100 » Sat Oct 01, 2016 12:45 pm

Good result Mike and thanks for the feedback, it is always welcome.

Brian

www.eBolt.co.uk www.ToolroomChucks.co.uk
1958 R26, (not so many bits now)
1978 R75/7, (a project bike)
1981 R80, (was a TIC)
1995 R1100RT, (speeding ticket the first day I rode it) (Sold)
http://www.eBolt.co.uk
http://www.ToolroomChucks.co.uk

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Galactic Greyhound
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Re: Running on One Cylinder! HELP!

Postby Galactic Greyhound » Sat Oct 01, 2016 1:01 pm

Thanks for the update!
Glad you found the problem.
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" - It works!

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Ruralman
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Re: Running on One Cylinder! HELP!

Postby Ruralman » Sat Oct 01, 2016 1:47 pm

That's brilliant Mike !
Regards
Keith


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Keith Hillier
Club Chairman
chairman@bmridersclub.com
----------------------------------
2011 R1200RT SE MU
2006 R1200GSA
2004 K1200RS
'Live to ride - ride to live'
\:D/ \:D/ \:D/ \:D/ \:D/


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