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V50 MK2 Ignition trouble

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Brian UK View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 21 Sep 2020 at 22:26
Originally posted by Ken-Guzzibear Ken-Guzzibear wrote:

big blocks are 3 ohmn

But they don't use the Bosch electronic boxes.

If 3 ohm coils get too hot, then a 5 ohm coil will run cooler.
Brian.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote George Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2020 at 17:51
Good afternoon to everybody. My ignition saga continues. I purchased from Gutsibits the new coils sold for the V50 Mk2 with Bosch electronic ignition. The following was noted:-
At start up the bike ran on the right hand cylinder only (and this has been a trait noticed on majority of the times that I have run the bike -I've never run the bike in anger on the road).
The left hand spark plug was checked and seen not to be sparking - the right hand plug being OK.
Subsequently I continuity checked the left hand cylinder wiring to the coil, the wiring from the coil to the electronic box and the wiring from the electronic box down to the harness terminal block for the electronic pick ups. Everything checked out as per the wiring diagram.
The bike was restarted , noted still to be running on the RHS cylinder.
The bike was stopped, plug cap removed and a brass screw inserted in the HT lead. Cranking the engine with the plug removed showed a good spark at the brass screw.
Plug cap exchanged (thinking that this may be the problem) and start up of the engine showed the bike to be still running on only the right hand cylinder at which point, with the engine running, I pulled off the LHS plug cap and the cylinder fired. It ran really nice with the plug cap sitting loosely on the plug for approx one minute after which it went onto one pot running again just on the RHS.
I am at a bit of a loss trying to come up with a reason for this latest experience. Does anybody have any suggestions possibly an electronic box or maybe a magnetic pick up problem. For info the carbs have all new jets, mixture adjusting screws (set at around one and a half turns open) and float levels checked OK. I would reiterate - the engine has always shown this sporadic / erratic running on the LHS. Best Regards - George     
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c13pep View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote c13pep Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2020 at 20:27
Just sitting the plug cap loosely on the plug is an old trick used to `boost` the spark. It was always tried when the spark was weak and possibly too weak to fire under compression. If you have not tried already swap plugs over but instinct says the electronic box on that side is possibly at fault. Maybe swapping individual units over one at a time would be the way to  go if that`s possible

CHRIS 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote George Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2020 at 21:06
Chris thanks for the reply. I was thinking along similar lines and tomorrow I think I will have a go at changing over the electronic boxes (both boxes have the same part number so it's a an exercise I can try quite quickly). I also note that pretty well at all times the RHS spark plug would spark whereas the LHS plug did not appear to spark at all.
Best Regards - George 

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2020 at 21:26
Are you certain the pickups are correctly set with regard to position and gap?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote George Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2020 at 22:20
Hi Brian - I feel quite confident that the pickups are set OK - I made a timing tool to set the pick up positions and air gaps. For a very brief time today the engine ran quite smooth and really sounded great, and  although it didn't last too long it gave me the encouragement to persevere with the bike. I'll post the results of the next 'trial' hopefully tomorrow.
Once again thanks for the reply - George. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2020 at 22:28
Yes, if it ran OK for a time, then those pickups are good.

Intermittent faults are always the worst. Yes it could be the Bosch electronics box.

When you get no spark on the left, turn the ignition off and see if you get a spark then. I believe you should. If not then it could well be the box.


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Post Options Post Options   Thanks (0) Thanks(0)   Quote George Quote  Post ReplyReply Direct Link To This Post Posted: 24 Sep 2020 at 17:18
Hi Brian and Chris and thanks for the replies. I checked the sparking at the plugs via operating the ignition switch and can confirm that the plugs did spark and continued as follows:-
1)changed the electronic boxes over. No change LHS still giving occasional firing, exhaust / silencer running cool. 
2)checked for sparking at the plugs via ignition switch on / off. LHS giving occasional spark, RHS OK.
3)changed out the LHS plug and confirmed both plugs sparking OK and restarted the engine. The engine was still running poorly on the LHS giving the occasional firing.
4)removed the plugs and noted that holding the LHS plug against the cylinder there was not any indication of a spark. However when placing the plug on the rubber carb connection sleeve and operating the ignition switch a spark was present at the electrode and a spark would jump from the plug body over to the rubber carb securing clips. The RHS plug appeared to give a consistent spark.
5)With the plugs removed and operating the ignition switch I could detect a clicking noise from what I believe is the regulator positioned above the airbox intake. My question is - is the clicking noise at this area normal when flicking the ignition switch? I had the garage in darkness and couldn't see any arcing from any components.
So that where I am up to to date and any comments appreciated. Best Regards - George
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Post Options Post Options   Thanks (0) Thanks(0)   Quote c13pep Quote  Post ReplyReply Direct Link To This Post Posted: 24 Sep 2020 at 19:49
I can`t see how a plug that should fire to earth can fire when resting on the rubber carb clips which are effectively insulated from earth, this would suggest a reversal of the polarity on the LHS.
On  the V50/3 I had with electronic Rita ignition there was a warning of damage to the system if the plugs were not earthed when ignition was on

CHRIS


Edited by c13pep - 24 Sep 2020 at 19:52
you can`t have any fun in a straight line

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Post Options Post Options   Thanks (0) Thanks(0)   Quote George Quote  Post ReplyReply Direct Link To This Post Posted: 24 Sep 2020 at 20:39
Hi Chris - I too can't see how a plug can fire if its insulated on the carb rubber. When the LHS plug sparks at its central electrode the plug body is not actually touching the rubber clips - it's resting solely on the rubber - its the intensity of the spark that jumps from the plug body to the metal clip (whilst also sparking at the electrode the same time - a bit like a frankenstein movie). I'm pretty baffled by the antics of this LHS plug especially as it shows next to no spark when the plug is pressed against the cylinder.
I've just been back out to the bike and done the ignition on / off exercise and although there was a small spark at the electrode with the plug against the cylinder the spark is much bigger and quite audible with the plug touching the rubber. I'd say the same result was noted when I went to the RHS plug. What plugs did you use in your bike - I'm using NGK BP6ES Plugs can be funny things but I'm not sure why one side should fire at not the other. I'm a bit nervous about causing damage especially with regard to your comment about the Rita ignition system. 
Tomorrow's another day but one day it'll be sorted - please keep thinking. George
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Post Options Post Options   Thanks (0) Thanks(0)   Quote George Quote  Post ReplyReply Direct Link To This Post Posted: 24 Sep 2020 at 21:00
Hi - regarding the comment in para 5) in my earlier post - that's a red herring. With the plugs inserted and the caps on there is not any click coming from the regulator area. Apologies for the bum steer.
George

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Post Options Post Options   Thanks (0) Thanks(0)   Quote George Quote  Post ReplyReply Direct Link To This Post Posted: 25 Sep 2020 at 14:13
Just a quick update - I checked the resistance of the magnetic pickups today and saw that they were good at 244 ohms. Having re instated the plug in socket and checking for spark at the plugs the bike was started and ran better today although there is the occasional miss beat on the LHS (also noting that the temperature of the LHS silencer was following that of the RHS although it did seem to be lagging a little).
I'm not too sure if  fiddling with the pick up wiring block has resulted in a better connection but it is something I'll take another look at. I've been trying to take note of every cough, splutter and anomaly, all adding to my confusion so now it's probably time to try the bike on the road and see what happens. I'll post on the forum after a test run hopefully tomorrow. 
Best Regards - George.  
 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote c13pep Quote  Post ReplyReply Direct Link To This Post Posted: 25 Sep 2020 at 15:36
For your bike the NGK website shows the BP8ES as the alternative to the ones in the manual and as many do on here I get mine from THE GREEN SPARKPLUG COMPANY just to make sure they are genuineOuch
In answer to your question I now use BP7ES in my V50/3 engines
It won`t be the first bike to suffer problems due to poor connections, generally a good spray with contact cleaner and a small wire brush does the job

CHRIS
you can`t have any fun in a straight line

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Post Options Post Options   Thanks (0) Thanks(0)   Quote George Quote  Post ReplyReply Direct Link To This Post Posted: 25 Sep 2020 at 20:01
Chris - thanks for the info and I will order a pair of plugs ASAP. I had intended to run the bike tomorrow as it seemed to be running OK however after the post I put on this afternoon the bugger went onto running just on the RHS cylinder. Checked  LHS plug - wet and oily. Swapped plugs over LHS now sparking OK, RHS sparking after wipe dry and a quick brush. I have read somewhere on the forum about the effect of having the wrong grade of plug so this is another simple avenue to go up. 
As a matter of interest - is it possible to fit new rings to a V50 - my bike having 55k on the clock.
Best Regards - George
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Post Options Post Options   Thanks (0) Thanks(0)   Quote c13pep Quote  Post ReplyReply Direct Link To This Post Posted: 25 Sep 2020 at 20:08
Fitting new rings is possible but best to do a compression test first as valves are usually the culprits if they are low
Rings are about £50 a set for the V50s you just have to shop around whereas `lapping ` valves in is very cheap in comparison

CHRIS
you can`t have any fun in a straight line

Monza
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