DLE-30 Running Rough
10-28-2013, 04:32 PM
#51
Yep. "Auto Advance" ignition is a misnomer. The timing retards for starting and idle, then goes to whatever you set it at at some point as the rpms go up. 28? 30? 35? or whatever. That's what the timing goes to at higher rpms.
Just like truckracer said....
AV8TOR
Just like truckracer said....
AV8TOR
10-29-2013, 08:18 AM
#52
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av8tor1977 and Truckracer. What you say makes sense to me but... on the first flip of trying to start the engine I would assume the plug would fire 30 deg before the piston reaches top dead centre and then if it take long enough for the prop to spin around such that ignition would now know that rpm is very low then the ignition could set timing closer to 0 for low rpm. I don't see how ignition set timing at 30 when not running and knows how to set it closer to 0 when I first flip the prop. Quote av8tor77: "The timing retards for starting and idle, then goes to whatever you set it at at some point as the rpms go up. 28? 30? 35?" Oh yea, one more question. I've always assumed a timing light would not work on our spark plug wires due to the fact the ground is the shielding such that flux generated by current in centre conductor is cancelled by current return on shield. Anybody tried a timing light? I really appreciate the insight you guys are giving me. Thx!
Last edited by j_keiter; 10-29-2013 at 08:24 AM.
10-29-2013, 11:21 AM
#53
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So after confirming timing light will not work on a ground current return shielded spark plug cable, I soldered up a test assembly using an old dle plug to make a timing light work on my dle 30. Could not use the throttle servo as bad radio interference due to test assembly so I had to unplug the throttle servo and move it manually. It appears the timing is low or somewhere closer to 0 degrees and stays there till you reach around 3000rpm at which point it suddenly jumps about 25 degrees in the advance direction. From 3000rpm to 7000 it looks to advance another 3-5 degrees. It never retards as the rpm increases as I have seen on some dirt bike 2-stoke graphs. So, some how the ignition allows a static set 30 degree advance but after first flip of trying to start the engine the ignition must set the timing close to zero and only advance as rpm increases. I would still think the first flip would give a spark at 30 deg advance. 
Everything is very crude here. I simply watched the ghost image of the light reflecting off the prop. Seemed to work pretty well. I simply approximated all the degree angles. Did you know that a spark will travel almost 4 inches at room temp but no more than a 1/4" at 50psi. That is the reason for the grey clay you see on the dle spark plug. I kept getting an arc on my dle plug instead of the ngk plug in the engine. I would pull the ngk plug and then it would fire. Put it back in engine and crank over prop and see big arc on external dle plug. Frustrating. Hacksawed threaded part of dle plug off and then packed with high dielectric clay. That worked. Ugh!
Jason
Everything is very crude here. I simply watched the ghost image of the light reflecting off the prop. Seemed to work pretty well. I simply approximated all the degree angles. Did you know that a spark will travel almost 4 inches at room temp but no more than a 1/4" at 50psi. That is the reason for the grey clay you see on the dle spark plug. I kept getting an arc on my dle plug instead of the ngk plug in the engine. I would pull the ngk plug and then it would fire. Put it back in engine and crank over prop and see big arc on external dle plug. Frustrating. Hacksawed threaded part of dle plug off and then packed with high dielectric clay. That worked. Ugh!
Jason
10-29-2013, 11:31 AM
#54
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This is not first hand and someone can chime in and correct me if I'm wrong then I will be better educated also. I'm told the ignition can sense the dwell of the magnet passing under the hall sensor and retard the spark on the first flip when the prop if flipped briskly. This makes sense as I've hand started many engines to a start on the first flip with no tendency for a kickback. If at full advance (static timing) I'd expect a few of these engines would bite me but they didn't so I felt they were indeed retarded on the first flip.
10-29-2013, 11:38 AM
#55
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Regarding a timing curve retard at or near full throttle, our engines really are not high performance enough and don't run at high enough RPM to see much if any gain doing this. This is common in free breathing, high RPM racing engines, especially with high compression and certain cam timings as cylinder pressures increase so much at speed, the amount of advance that works well in the mid-RPM ranges will actually cause detonation and loss of power when the engine is at full song. Anybody that has ever sat on, behind or in front of any racing engine of any kind knows what I mean by full song! Many racing classes do not allow high RPM ignition retard to reduce costs.
10-29-2013, 11:43 AM
#56
Yes Truck Racer, you are again correct. It is a smart little chip in the ignition as Bill from CH Ignitions used to say. It does know what is going on rpm wise by measuring the time from sensor activation by the magnet till the sensor de-activates when the magnet leaves the sensor. If it is a very slow movement, such as moving the prop while we are setting the timing, it goes to full advance. That allows us to set the timing max advance. Then if it senses a faster crank movement, such as with a brisk hand flip for starting, it retards the timing to allow for a safer start. The timing stays retarded at idle for a smoother, lower idle, then depending on the built in design of the particular ignition unit, it advances until it eventually reaches full advance, and what we had set it at, at higher rpms.
I agree with Bill; it is one smart little computer chip!
AV8TOR
I agree with Bill; it is one smart little computer chip!
AV8TOR
10-29-2013, 12:13 PM
#58
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Yes Truck Racer, you are again correct. It is a smart little chip in the ignition as Bill from CH Ignitions used to say. It does know what is going on rpm wise by measuring the time from sensor activation by the magnet till the sensor de-activates when the magnet leaves the sensor. If it is a very slow movement, such as moving the prop while we are setting the timing, it goes to full advance. That allows us to set the timing max advance. Then if it senses a faster crank movement, such as with a brisk hand flip for starting, it retards the timing to allow for a safer start. The timing stays retarded at idle for a smoother, lower idle, then depending on the built in design of the particular ignition unit, it advances until it eventually reaches full advance, and what we had set it at, at higher rpms.
I agree with Bill; it is one smart little computer chip!
AV8TOR
I agree with Bill; it is one smart little computer chip!
AV8TOR
10-29-2013, 01:14 PM
#60
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I wondered how long it would take for that comment to come around. Well sir, so far there is no DA in that size range. Yes, I know one has been in the works for years now but not out yet. I'm sure when it comes out it will have its teething problems like most every new engine ..... DA or otherwise.
While there is a lot of discussion in this thread, for the most part a DLE 30 is about as reliable as an engine can get. Discussions just help people understand their engines better.
While there is a lot of discussion in this thread, for the most part a DLE 30 is about as reliable as an engine can get. Discussions just help people understand their engines better.
10-29-2013, 01:21 PM
#61
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Quote from av8tor1977 "It does know what is going on rpm wise by measuring the time from sensor activation by the magnet till the sensor de-activates when the magnet leaves the sensor. If it is a very slow movement, such as moving the prop while we are setting the timing, it goes to full advance."
This might explain why sometimes when I get tired of flipping and do a half ass slow flip the dang thing kicks back hard and dings my prop on my home made chicken stick. I aint flippin that thing by hand. Even with a glove. Ain't doin it. I'll try spinning the hub faster next time when I do a timing test to see if I can get the ignition to spark at 0 instead of 30.
THANK YOU av8tor1977. First time anybody explained why static timing is at 30 deg but starting is not.
This might explain why sometimes when I get tired of flipping and do a half ass slow flip the dang thing kicks back hard and dings my prop on my home made chicken stick. I aint flippin that thing by hand. Even with a glove. Ain't doin it. I'll try spinning the hub faster next time when I do a timing test to see if I can get the ignition to spark at 0 instead of 30.
THANK YOU av8tor1977. First time anybody explained why static timing is at 30 deg but starting is not.
10-29-2013, 02:44 PM
#62
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Quote from av8tor1977 "It does know what is going on rpm wise by measuring the time from sensor activation by the magnet till the sensor de-activates when the magnet leaves the sensor. If it is a very slow movement, such as moving the prop while we are setting the timing, it goes to full advance."
This might explain why sometimes when I get tired of flipping and do a half ass slow flip the dang thing kicks back hard and dings my prop on my home made chicken stick. I aint flippin that thing by hand. Even with a glove. Ain't doin it. I'll try spinning the hub faster next time when I do a timing test to see if I can get the ignition to spark at 0 instead of 30.
THANK YOU av8tor1977. First time anybody explained why static timing is at 30 deg but starting is not.
This might explain why sometimes when I get tired of flipping and do a half ass slow flip the dang thing kicks back hard and dings my prop on my home made chicken stick. I aint flippin that thing by hand. Even with a glove. Ain't doin it. I'll try spinning the hub faster next time when I do a timing test to see if I can get the ignition to spark at 0 instead of 30.
THANK YOU av8tor1977. First time anybody explained why static timing is at 30 deg but starting is not.
On this super-ignition, i can set many points to increase advance ( or apply less delay to the spark to jump') and also at hi rpm i can 'retard' aplying more delay to spark jump. Or i can set a rpm limit, decreasing to zero the 'advance'. This way engine cannot exceed the limit programmed.
RCEXL ignition apply some amount of delay after the magnet leaves the hall sensor, also at engine start.
The delay time is function of rpm and the time the magnet is under the sensor.
My experience is : The standard A01 or A02 'curve' works well in almost gas engine, two or four stroke.
On a new ignition model received time ago, i've seen (and hear) at lower rpm (less than 600 rpm) there are two sparks each time the magnet leaves the hall sensor, with 10ms , but 'advance' is almost 0 ( at TDC)
Best regards
Last edited by mpascual; 10-29-2013 at 02:51 PM.
10-29-2013, 03:05 PM
#64
Quote from av8tor1977 "It does know what is going on rpm wise by measuring the time from sensor activation by the magnet till the sensor de-activates when the magnet leaves the sensor. If it is a very slow movement, such as moving the prop while we are setting the timing, it goes to full advance."
This might explain why sometimes when I get tired of flipping and do a half ass slow flip the dang thing kicks back hard and dings my prop on my home made chicken stick. I aint flippin that thing by hand. Even with a glove. Ain't doin it. I'll try spinning the hub faster next time when I do a timing test to see if I can get the ignition to spark at 0 instead of 30.
THANK YOU av8tor1977. First time anybody explained why static timing is at 30 deg but starting is not.
This might explain why sometimes when I get tired of flipping and do a half ass slow flip the dang thing kicks back hard and dings my prop on my home made chicken stick. I aint flippin that thing by hand. Even with a glove. Ain't doin it. I'll try spinning the hub faster next time when I do a timing test to see if I can get the ignition to spark at 0 instead of 30.
THANK YOU av8tor1977. First time anybody explained why static timing is at 30 deg but starting is not.
AV8TOR
10-29-2013, 05:50 PM
#65
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Yuck. Thanks for dragging down a very informative and helpful thread with a completely useless and irrelevant opnion. 
The OP is not asking for advice on the best replacement engine for his DLE. He's trying to learn and those of us that have open and inquisitive minds instead of blind brand loyalty are coming along for the ride. Absolutely nothing is added to this thread by throwing out a shameless plug for a different brand that doesn't even offer a product similar to the one that is the subject of this thread. There are plenty of DA thread elsewhere in this forum. Please go find one.
The OP is not asking for advice on the best replacement engine for his DLE. He's trying to learn and those of us that have open and inquisitive minds instead of blind brand loyalty are coming along for the ride. Absolutely nothing is added to this thread by throwing out a shameless plug for a different brand that doesn't even offer a product similar to the one that is the subject of this thread. There are plenty of DA thread elsewhere in this forum. Please go find one.
Last edited by irocbsa; 10-29-2013 at 05:56 PM.
10-30-2013, 03:47 AM
#66
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Re: the tunable ign. module? I figured it would be just a matter of time before we see a module like this available to anyone willing to pay the price. There's been similar around for motorcycles and snowmobiles for many years. "Tuners" really get into this kind of thing? Personally, I don't have the motivation to use, or even be bothered with this kind of tuning (the works good enough as is clause in effect). There are others though, that seem to be willing to pay quite a bit of money for this ability? Thinking a hobby like ours actually attracts this kind of person? Therefor, it's just a question of time and marketing....
-Al
-Al
10-30-2013, 04:37 AM
#67
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Tuning spark curves? Personally, I'd love to have that ability. In theory, I should be good at it since engine calibration is what I do for a living. 
This one will be simple compared to what I'm used to.
This one will be simple compared to what I'm used to.
10-30-2013, 06:01 AM
#68
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"Do-able" yes, but why? Do you think you might be able to get another 10% out of it? 5%? 2%? 
Somebody may be able to do something about the way they run in mid range though. THAT goal might make it worth the hassle?
And knowing what you do Brit, you might want to check into it? -Al
Somebody may be able to do something about the way they run in mid range though. THAT goal might make it worth the hassle?And knowing what you do Brit, you might want to check into it? -Al
10-30-2013, 06:34 AM
#69
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Right, I think a lot of the mid-range issues that show up are related to the simplisitic "curve" that is calibrated into the modules. I know it's not a big deal and the mid-range burble really doesn't affect anything other than audible pleasability, but it would be cool to fiddle with.
10-30-2013, 10:29 AM
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I never worry about the midrange burble. I've found by ignoring it I have far less engine problems.
From what I've seen over the years is the guys that have the most engine problems are the ones who are always tinkering with them
From what I've seen over the years is the guys that have the most engine problems are the ones who are always tinkering with them
Last edited by kerwin50; 10-30-2013 at 10:32 AM.
10-30-2013, 11:48 AM
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I learned not to worry about it as well. All I'm saying is that is that you might be able to clean it up, if you wanted to, with a module that has a calibrateable spark curve.
10-30-2013, 12:17 PM
#73
Re: that midrange burble, I've said it before and I'll say it again. We just need a Walbro type carb but with an adjustable midrange circuit. I wish someone would make one. I keep thinking about having a look at what it would take, but never get around to it....
If they ever came out with one, they would sell like crazy I believe.
AV8TOR
If they ever came out with one, they would sell like crazy I believe.
AV8TOR
10-30-2013, 12:35 PM
#74
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Some guys made their own 3 needle Walbro. Was discussed on another forum some years back. These were mostly used on the then new BME 115 before they came out with a new reed block that resolved the problem. I believe that BME actually made a few of these carbs also. At any rate, the 3 needle carb has been done though these would have been the larger frame carbs.
To this day, the DA50 still has a midrange problem and over the years some have resolved this by using of all things ..... Chinese engine reed blocks that use the "A" frame configuration rather than the DA pyramid. Of course, a heavier prop load always seems to minimize the problem.
To this day, the DA50 still has a midrange problem and over the years some have resolved this by using of all things ..... Chinese engine reed blocks that use the "A" frame configuration rather than the DA pyramid. Of course, a heavier prop load always seems to minimize the problem.
