Author Topic: Fuel from exhaust - no start whackness.  (Read 1325 times)

Offline billday

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Re: Fuel from exhaust - no start whackness.
« Reply #25 on: August 09, 2019, 03:52:43 PM »
IMHO that Techron stuff looks, smells, tastes, feels just like Kerosene

That's just, like, your opinion, man.
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Offline DJEwen

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Re: Fuel from exhaust - no start whackness.
« Reply #26 on: August 15, 2019, 03:33:26 PM »
I installed the new temperature sensor, reinstated the radiator, topped up the coolant, went for start and she fired up and idled like normal, warmed up, fan kicked in and out, all was well so I went out on the road.

Out on the road I found an issue and this may be completely unrelated to the temp sensor change but immediately when demanding generous throttle the bike spluttered, popped, backfired. This went on for about 20 miles before it started to get a little better. I stopped for half an hour, got back on the bike and it was slightly improved (or at least it felt like it) What Iíve realised is that provided Iím smooth or of you like, linear in my request for throttle the bike responds normally, if I wind her round and demand wide open throttle itís splutters, backfires and pops.

The changes are obviously the temperature sensor itself, but also, the spark plugs obviously had petrol pouring over them during the fault find as you can see from the earlier video. I had pulled them, dried them and reinstated them.

Itís strange itís only doing this under WOT.

If anyone has any suggestions or experience with this that would be great? Thanks in advance. Dave.
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Offline Soggz

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Re: Fuel from exhaust - no start whackness.
« Reply #27 on: August 15, 2019, 06:03:43 PM »
I installed the new temperature sensor, reinstated the radiator, topped up the coolant, went for start and she fired up and idled like normal, warmed up, fan kicked in and out, all was well so I went out on the road.

Out on the road I found an issue and this may be completely unrelated to the temp sensor change but immediately when demanding generous throttle the bike spluttered, popped, backfired. This went on for about 20 miles before it started to get a little better. I stopped for half an hour, got back on the bike and it was slightly improved (or at least it felt like it) What Iíve realised is that provided Iím smooth or of you like, linear in my request for throttle the bike responds normally, if I wind her round and demand wide open throttle itís splutters, backfires and pops.

The changes are obviously the temperature sensor itself, but also, the spark plugs obviously had petrol pouring over them during the fault find as you can see from the earlier video. I had pulled them, dried them and reinstated them.

Itís strange itís only doing this under WOT.

If anyone has any suggestions or experience with this that would be great? Thanks in advance. Dave.
synch the throttle bodies, maybe?
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Offline The Mighty Gryphon

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Re: Fuel from exhaust - no start whackness.
« Reply #28 on: August 15, 2019, 06:59:42 PM »
Spark plugs with a lot of carbon on them often have issues with firing under high cylinder pressure which can occur when going wide open throttle.  You might want to pull the plugs and change them or at least give them a good cleaning before going much deeper into other stuff.
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Offline volador

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Re: Fuel from exhaust - no start whackness.
« Reply #29 on: August 16, 2019, 02:57:56 AM »
I installed the new temperature sensor, reinstated the radiator, topped up the coolant, went for start and she fired up and idled like normal, warmed up, fan kicked in and out, all was well so I went out on the road....

Itís strange itís only doing this under WOT.

1) Adjust the Throttle Position Switch
2) Dodgy Hall Effect Sensor
3) Misbehaving AFM
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Offline DJEwen

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Re: Fuel from exhaust - no start whackness.
« Reply #30 on: August 16, 2019, 05:09:46 AM »
synch the throttle bodies, maybe?

They're synced.

Spark plugs with a lot of carbon on them often have issues with firing under high cylinder pressure which can occur when going wide open throttle.  You might want to pull the plugs and change them or at least give them a good cleaning before going much deeper into other stuff.

Thanks Gryph, a few people have suggested changing the plugs, the characteristics certainly match the symptoms of a spark issue, be it via Plugs, HT leads or coils. Do you know of a good spark plug cleaning process?


1) Adjust the Throttle Position Switch
2) Dodgy Hall Effect Sensor
3) Misbehaving AFM

Potentially, I think investigation of spark will be the first exploration given the issue arising since the plugs were saturated and removed.
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Offline Soggz

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Re: Fuel from exhaust - no start whackness.
« Reply #31 on: August 16, 2019, 10:01:48 AM »
To clean mine, I heat till red with a blowtorch, hold in a vice or pliers, blow out with an airline, wirebrush and re-gap. They come up as good as new. Also, I have found, heating them, then putting back into the bike still hot, gives them a nice warm start, and helps initial ignition. Hope this helps.
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Offline The Mighty Gryphon

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Re: Fuel from exhaust - no start whackness.
« Reply #32 on: August 16, 2019, 10:27:57 AM »
Cleaning:  Back in the day when I rode bikes aith 2 stroke engines we had a spark plug cleaner that cleaned them with abrasive and compressed air. 

I've used carb cleaner and other solvents with less than stellar results.  I've heated them and wire brushed the carbon off and then installed the still warm plug to start my snowblower or lawnmower but the head sucks the heat out of the plug to quickly to give any advantage on a bigger engine.

If it were my bike and the plugs had more than a couple thousand miles on them I would spring for a set of new NGK plugs.  They are fairly cheap and could save you a lot of time chasing other stuff.
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Offline DJEwen

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Re: Fuel from exhaust - no start whackness.
« Reply #33 on: August 16, 2019, 10:32:12 AM »
To clean mine, I heat till red with a blowtorch, hold in a vice or pliers, blow out with an airline, wirebrush and re-gap. They come up as good as new. Also, I have found, heating them, then putting back into the bike still hot, gives them a nice warm start, and helps initial ignition. Hope this helps.

Thanks, Soggz.

Cleaning:  Back in the day when I rode bikes aith 2 stroke engines we had a spark plug cleaner that cleaned them with abrasive and compressed air. 

I've used carb cleaner and other solvents with less than stellar results.  I've heated them and wire brushed the carbon off and then installed the still warm plug to start my snowblower or lawnmower but the head sucks the heat out of the plug to quickly to give any advantage on a bigger engine.

If it were my bike and the plugs had more than a couple thousand miles on them I would spring for a set of new NGK plugs.  They are fairly cheap and could save you a lot of time chasing other stuff.

Cheers, Gryph. Are the NGKís preferred? Thatís what was in the moto when I purchased it but I added new Bosch ones during the build.
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Offline Soggz

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Re: Fuel from exhaust - no start whackness.
« Reply #34 on: August 16, 2019, 10:48:34 AM »
New Iridium plugs work great in my CX. Havnt tried them in the K yet.
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Offline mw074

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Re: Fuel from exhaust - no start whackness.
« Reply #35 on: August 16, 2019, 11:16:07 AM »
 For years I would pull my K bike plugs and put the used ones into my torpedo style space heaters. The NGKs, Champions, ect would foul out in no time. The Bosch plugs would last for years. Just sayin'............
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Offline DJEwen

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Re: Fuel from exhaust - no start whackness.
« Reply #36 on: August 16, 2019, 03:53:36 PM »
Sheís fixed!

I pulled the plugs and cleaned them as advised in earlier replyís, went out on the road and the moto is behaving better than ever! Thanks all for the advice.



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Offline The Mighty Gryphon

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Re: Fuel from exhaust - no start whackness.
« Reply #37 on: August 17, 2019, 07:16:19 PM »
 :twothumbsupp
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Offline DJEwen

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Re: Fuel from exhaust - no start whackness.
« Reply #38 on: August 18, 2019, 04:59:48 PM »
I had the moto out on a 140 mile spirited run and she ran beautifully, better than ever I would say. Unfortunately in the last mile from my house, and after sitting in traffic at high temperatures, I opened her up on wide open throttle for the last stretch and it started to splutter again, exactly the same symptoms as earlier.

Iím wondering if the HT leads may be bad? They were very difficult to give any internal form of restoration during the build as they are sealed units but I cleaned as best I could. Iíve taken some photos and youíll probably agree they need replaced. Iíve ordered a set of Ram Power Leads from BSK speedworks. I havenít pulled the plugs to check for further fouling again but the only visual change I noted upon putting the moto away was that I used a touch more oil than usual, say maybe 2 to 3mm in the sight glass, however, nearly all of the 140 miles were hard WOT miles.







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Re: Fuel from exhaust - no start whackness.
« Reply #39 on: August 18, 2019, 05:14:21 PM »
Iím wondering if the HT leads may be bad? .
Sure, and by the way, don't expect to find work as a hand model unless it's as the Before model.

Clean the coil terminals themselves and determine both the primary and secondary lead values with your new multimeter.
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Offline Soggz

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Re: Fuel from exhaust - no start whackness.
« Reply #40 on: August 18, 2019, 05:52:38 PM »
I had the moto out on a 140 mile spirited run and she ran beautifully, better than ever I would say. Unfortunately in the last mile from my house, and after sitting in traffic at high temperatures, I opened her up on wide open throttle for the last stretch and it started to splutter again, exactly the same symptoms as earlier.

Iím wondering if the HT leads may be bad? They were very difficult to give any internal form of restoration during the build as they are sealed units but I cleaned as best I could. Iíve taken some photos and youíll probably agree they need replaced. Iíve ordered a set of Ram Power Leads from BSK speedworks. I havenít pulled the plugs to check for further fouling again but the only visual change I noted upon putting the moto away was that I used a touch more oil than usual, say maybe 2 to 3mm in the sight glass, however, nearly all of the 140 miles were hard WOT miles.








2 to 3 mm Of oil seems a lot. Did you let it drain down for a day to see exactly how much you used? The oil gets thrown around a bit and takes its time to get back into the sump.
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Re: Fuel from exhaust - no start whackness.
« Reply #41 on: August 18, 2019, 07:21:28 PM »
The allowable oil consumption according to BMW is 0.15lt per 100 km. The amount of oil consumed when the oil level drops from the maximum mark to the minimum mark on the sight glass is 0.6liters. The distance from the maximum to minimum levels on the sight glass  is 25mm. 0.15lt consumption equals 25% of the distance between the maximum and minimum marks or 6.25mm. David believes oil consumption dropped the level 2mmĖ3mm. Therefore, the oil consumption of David's moto did not exceed the allowable oil consumption. It was approximately half the allowable oil consumption, although it might have exceeded its customary oil consumption.
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Offline DJEwen

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Re: Fuel from exhaust - no start whackness.
« Reply #42 on: August 19, 2019, 01:43:32 PM »
Sure, and by the way, don't expect to find work as a hand model unless it's as the Before model.

Clean the coil terminals themselves and determine both the primary and secondary lead values with your new multimeter.

Before model is my kind of thing :D

While awaiting my new leads I performed tests of the coils, are the values of 12.6 Kohms at the high voltage terminals and 2.6 ohms at the primary coils as quoted in Vogles troubleshooting guide ĎTHEí values that are supposed to be present and is there any leeway in these? He states he tested two spare and they ďgive you an idea of what to expectĒ

My reading are as follows:

1 & 4: 2.6 ohms and 10.5 kohms
2 & 3: 2.6 ohms and 12.7 kohms

Does this indicate a bad #1-4 Coil Pack?







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Re: Fuel from exhaust - no start whackness.
« Reply #43 on: August 19, 2019, 02:19:08 PM »
My reading are as follows:
1 & 4: 2.6 ohms and 10.5 kohms
2 & 3: 2.6 ohms and 12.7 kohms
Does this indicate a bad #1-4 Coil Pack?
10.5 ohms represents ~18% value drop. That seems significant. Do the plugs in 1 and 4 look different from those in 2 and 3? Have you done a running or cranking inspection of the engine in the dark looking for spark leakage in the coils and plug wires?
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Offline DJEwen

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Re: Fuel from exhaust - no start whackness.
« Reply #44 on: August 19, 2019, 02:41:15 PM »
10.5 ohms represents ~18% value drop. That seems significant. Do the plugs in 1 and 4 look different from those in 2 and 3? Have you done a running or cranking inspection of the engine in the dark looking for spark leakage in the coils and plug wires?

Indeed significant. I havenít yet done a running inspection in the dark, Iíll do that tomorrow evening. I also havenít re-pulled the plugs but Iíll do that also tomorrow.

I have a spare coil from the other bike, I couldnít get any reading across the high power outputs.
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Offline DJEwen

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Re: Fuel from exhaust - no start whackness.
« Reply #45 on: August 20, 2019, 12:24:06 PM »
I ran the ďdark testĒ and there was no indication of any spark leakage. I also individually tested each lead and I was unable to obtain a signal from two of them, I think mostly due to being able to reach the contact surface. All plugs were the same colour, but then there was only 1 mile of miss firing before I put the moto away.

The new leads are on order (since Sunday passed) and today I ordered a used coil from Motorworks. It comes Pre tested and with a 6 month warranty for £40. A single new unit was £170.
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Offline DJEwen

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Re: Fuel from exhaust - no start whackness.
« Reply #46 on: August 23, 2019, 05:18:21 AM »
The new RAM Power HT Leads arrived yesterday directly from the manufacturer, Realm Engineering (purchased from BSK Speedworks), they appear to be of excellent quality. The used coil pack also arrived from Motorworks (which comes with a 6 month warranty) I tested then installed all in the moto and took her out on the road, the miss-fire has been eradicated.






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Re: Fuel from exhaust - no start whackness.
« Reply #47 on: August 23, 2019, 06:15:16 AM »
Brilliant! I would tend to hold off on the street party for a hundred or so miles though. Warranty expires in February so flog that moto now while conditions allow it. Maybe you can get another for free where the warranty will extend into summer.
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Offline Scott_

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Re: Fuel from exhaust - no start whackness.
« Reply #48 on: August 23, 2019, 06:35:25 AM »
I have the RAM wires on both my bikes, I really like them and they have been holding up real well.(I've had them a while now, got them when they were 1st released)
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Offline DJEwen

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Re: Fuel from exhaust - no start whackness.
« Reply #49 on: August 23, 2019, 07:40:39 AM »
flog that moto now while conditions allow it.


 :yawl: I'm keeping it forever!

I have the RAM wires on both my bikes, I really like them and they have been holding up real well.(I've had them a while now, got them when they were 1st released)

Glad to hear it, Scott. They certainly seem very well manufactured.
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