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Ural 650 with intermittent spark


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This has always been a "hobby bike" to me, I have other bikes, so I've had a "take or leave it" attitude to it previously but want to get to the bottom of the issue as I really love the bike

I've owned and maintained my own and friends bikes for more than 40 years now and have worked on most makes and models from "points and kickstart" technology through to the more modern machines but I've got a strange one with my 95 Ural 650 (Neval Soviet Knight) that's got me stumped

The bike has always been a right mare to start and has become know amongst my friends as the "Ten Kick Cossack" as it takes at least 10 kicks to start it, so many that I have bent both the centre and side stands a few times from my efforts

A little background :….


I bought the bike from a chap who had left it lying in a hedge half way up a welsh mountain for a couple of years as I have always loved anything Russian, like a challenge and thought it had potential

The right cylinder was full of water, which I drained with a syringe and left it to dry in the back of the garage for a full summer

I assumed that I would need to rebuild at least that cylinder, but one day I thought I would try a compression test and see how it looked, the test was pretty good, equal-ish on both sides so I cleaned out the carbs, checked for spark and gave her a few kicks

She did eventually fire up and although there was a little knocking from the right cylinder, ran quite well. The clutch wasn't operating and the gearbox was full of water but that was what you would expect from languishing in a hedge.

After stripping out the clutch, changing out all the fluids etc I spent some time on her repainting and the usual restorative work, took her for an MOT which she passed so decided to run her locally for a while and see how it goes. I have done about 1500 miles on her since then and this problem has persisted throughout that time

A summary of the issue ....

The bike has always been difficult to start no matter what the engine temperature, she even fails from a bump start when being stubborn, but once started has never stopped or misfired etc, she also idles pretty well, never cutting out on me

The most consistent way to start the bike has always been to turn in the idle screws an additional full turn, use choke and tickle if she's cold then kick, kick, kick and keep kicking until she fires or exhaustion sets in, then turn the idles back down

I always assumed it was a fuel issue and blamed the K65 carbs that came with her so eventually bought a set of K68's which didn't improve the situation. On closer inspection I noticed the spark would sometimes be intermittent but as it's difficult to check the spark and kick at the same time due to the location of the kickstart I could never be sure, I always thought it was a weak spark though (but have seen worse running)

The previous owner told me that it was electronic ignition but during the lockdown I have revisited the issue and found that it is actually running points. I have bought and fitted a Sovek electronic ignition module, the type with the magnetic pickup, new coil, HT leads, plug caps and spark plugs. I have also installed several additional earths between the engine and frame as there was only the one that bolts to the top of the engine, hoping that this may improve things

I have bypassed the kill switch by powering the coil and module straight from the battery positive via a new lead to take a wiring issue out of the equation

If I unbolt the rotor from the camshaft and spin it by hand a nice spark is visible at the spark plug each time one of the firing points passes the sensor, even if I turn it really slowly, this is consistent and I have not seen it fail to spark this way

When I bolt the rotor back onto the camshaft and use the kickstart to turn the rotor, the spark is very intermittent, but good when it does spark, so no change between the standard points setup and the complete new ignition system !

I really am baffled now so if anyone of you very knowledgeable people can offer any advice it would be very much appreciated

 

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Hi - have you read through this recent thread? viewtopic.php?f=5&t=57162&sid=400cc078e ... 51e16b7703 My four pennyworth is toward the end and my poor starting issue was resolved by junking the recently fitted Sovec module & coil, but like you, I'd spent hours playing with the carburation first. One question I do have, what coil were you running on the original points setup?

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I read the original post yesterday evening and could not come up with any sort of answer at that time so I went to sleep on it. During the night I think I may have come up with an answer for this very strange problem. The problem could possibly be caused by the alternator and/or it's regulator. As per your description it produces spark when you remove the rotor and test it by hand so the alternator is not being turned by the engine. When you connect it and start kicking the engine over you are also rotating the alternator. If there is a problem in the alternator it may be causing problems such as inducing alternating current on the battery positive post which can and will cause cancellation of DC power on the power line when the negative AC pulse neutralizes the positive DC voltage so at that moment the ignition coil is not charging and so can not create a spark across the spark plug gap when the points open or the electronic ignition IGBT transistor turns off, which also causes a spark from the ignition coil because the ignition coil is not charged at that moment. It could be one or more of the rectifier diodes on the rectifier board in the alternator have shorted out. You can test this by disconnecting the power wire at the battery and have only the wire from the battery to the ignition system with nothing else on the bike connected to the battery. Then have both spark plugs removed from the heads but grounded to the heads with the spark plugs connected to the spark plug wires. When you rotate the engine with the kick start lever with good sparks created across the spark plug gaps like when you test by hand without rotating the engine then you know know the problem is with the electrical system of the bike and not the ignition system. I could very well be wrong about this but you can test this without any cost except your time.

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Quick Update ....

 

I got fed up trying to get the Sovek unit working so went back to the points set up

 

After reading a few other posts I thought I would try fitting a condensor from  a Jap bike, after doing that and cleaning the points after filing them flat she produced a nice bright spark !

 

Started her a few times at diferent temperatures and it all seems good so far

 

I'll keep you all updated

 

! I think you may well be right about my Sovek unit Rod !

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I'm not a great fan of Sovek ignitions these days but that doesn't sound like the usual problem with them. Did you use a new coil or keep the points one? It's usually termed the "dog " coil for obvious reasons and is about as good at sparks as one. Used to fit Harley 5 ohm coils then went to 3.5ohm or Honda coils. Lately after some ignition failure I've taken a closer look at coil primary resistance. These days I use Boyer Brandsen ignitions meant for Norton Comandos. The maths tell me to use a 4ohm coil with the regulator I'm using. Kawaski coil fit the bill. I'm going to look harder at coils for Sovek ignitions as the ones supplied vary wildly in resistance, some being very low. Personally, If I had your bike I'd look at new rings or Chinese pistons. There are excellent rings available from Poland. Avoid the Ukranian ones. Russian one are so-so.

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7 hours ago, Serious Black said:

I'm not a great fan of Sovek ignitions these days but that doesn't sound like the usual problem with them. Did you use a new coil or keep the points one? It's usually termed the "dog " coil for obvious reasons and is about as good at sparks as one. Used to fit Harley 5 ohm coils then went to 3.5ohm or Honda coils. Lately after some ignition failure I've taken a closer look at coil primary resistance. These days I use Boyer Brandsen ignitions meant for Norton Comandos. The maths tell me to use a 4ohm coil with the regulator I'm using. Kawaski coil fit the bill. I'm going to look harder at coils for Sovek ignitions as the ones supplied vary wildly in resistance, some being very low. Personally, If I had your bike I'd look at new rings or Chinese pistons. There are excellent rings available from Poland. Avoid the Ukranian ones. Russian one are so-so.

My MT-11 came with points ignition and a red dog poo coil that actually made good spark, until it diden't. It left me stranded in a parking lot. It was running just fine until I was finished shopping and attempted to start it. I put in the new spare points and condensor I keep in the tool bag but it was still dead. I got it home after using the few Russian curse words I learned and calling my wife to come get us. I obtained a Harley ignition coil and got it running again. I did an autopsy on the red dog poo coil by carefully cutting away the red varnished cloth cover and found the problem. The solder used to connect the fine copper secondary coils to the thicker copper wires that connect to the screw terminals that poke out of the red cloth had corroded and failed because the red varnished cloth had not sealed up the internals of the coil at all. I did find something interesting in it's construction. There is one primary coil wrapped around the then metal strips of steel that connects to the 12 volts positive terminal and the terminal that connects to the points. Around that coil are two coils separated by an insulated separation disc. They are connected to each other through that insulated separation disc with the other ends of the coils connected to the terminals that connect to the spark plug wires. What you have are two 6 volt secondary coils connected in series inside that red dog poo ignition coil that share a single primary coil.  

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Some very interesting information in the feedback which is appreciated ... Thanks Gents

The sovek unit turned out to be faulty, a replacement is on the way but in the meantime, the points with a jap condenser are working just fine

I have ordered a Thorcap condenser (mentioned on SS) and will report back once I've had a chance to test it out

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On 2/3/2021 at 12:03 PM, z400d3 said:

Some very interesting information in the feedback which is appreciated ... Thanks Gents

The sovek unit turned out to be faulty, a replacement is on the way but in the meantime, the points with a jap condenser are working just fine

I have ordered a Thorcap condenser (mentioned on SS) and will report back once I've had a chance to test it out

The original condensor that came with my points ignition system developed a leak. Yes, I said it had a leak and that's not a mistake. I noticed the engine was getting hard to start and so pulled a spark plug to check the spark across the gap. It was weak and missed jumping the gap sometimes. I pulled the timing cover and noticed the condensor had developed a wax leak. You could see where it was easing out of a split in the metal body of the condensor. They use wax as an insulator between thin sheets of aluminium wound in a spiral to make them. I went to a small engine shop near me and picked up a new condensor and strong sparks across the spark plug gaps was returned along with easy, one kick starting after the three pre-lube kicks.

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On 2/1/2021 at 3:43 AM, Scott E said:

My MT-11 came with points ignition and a red dog poo coil that actually made good spark, until it diden't. It left me stranded in a parking lot. It was running just fine until I was finished shopping and attempted to start it. I put in the new spare points and condensor I keep in the tool bag but it was still dead. I got it home after using the few Russian curse words I learned and calling my wife to come get us. I obtained a Harley ignition coil and got it running again. I did an autopsy on the red dog poo coil by carefully cutting away the red varnished cloth cover and found the problem. The solder used to connect the fine copper secondary coils to the thicker copper wires that connect to the screw terminals that poke out of the red cloth had corroded and failed because the red varnished cloth had not sealed up the internals of the coil at all. I did find something interesting in it's construction. There is one primary coil wrapped around the then metal strips of steel that connects to the 12 volts positive terminal and the terminal that connects to the points. Around that coil are two coils separated by an insulated separation disc. They are connected to each other through that insulated separation disc with the other ends of the coils connected to the terminals that connect to the spark plug wires. What you have are two 6 volt secondary coils connected in series inside that red dog poo ignition coil that share a single primary coil.  

Well that IS interesting!

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If you want to keep the points Boyer also make a box that continues to use the points (although you HAVE TO disconnect the capacitor). I've used them and they work very well. You get the "advantage" of an easy swap back to points should there be a problem.

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