My official testing of several different aftermarket CDIs

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crmachineman

New Member
May 24, 2012
259
2
0
New Hampshire
Indeed. Unfortunately Norms bench test method bears no useful information, unless you are only interested in the spark advance for idle speeds. And like Matt said, Gasbike rips off American innovators, sending units to China for cloning, so I think it's uncool to buy from them. That happened to my product, and now they are attempting to horn in on the CDI technology that others devoloped. They couldn't copy the HD lightning because Dan filled the box with resin, so Gasbike copied the bottle rocket, which was made with cheap components. Now, I'm starting to hear that many of those Gasbike units have failed! Well, that's what I call poetic justice! I'm glad that things are panning out like this. I support Dan's HD Lightning because I like the performance, and that's it. Norm got all upset because I didn't post a bunch of numbers and graphs to impress people with smoke and mirrors. My decision to carry the HD Lightning has nothing to do with whether or not I'm friends with the guy, but it has everything to do with the performance of his product. Norm talks like I'm business partners with Dan. We are not. Norm may have an axe to grind against me and Dan for whatever reason, I don't know why. Whatever. That's my 2 cents on the matter folks. This is a soap opera that I care not to engage in, so don't expect me to be engaging in a pissing match about this. I was asked to comment of this, so there it is folks. You could give me a gasbike unit for free, and I still would not run it because I don't want to push my bike home.
:-||
 

Goat Herder

Gutter Rider
Apr 28, 2008
6,237
20
38
N.M.
I am watching this thread. I trust VMB and what he comes up with. As for a stock china cdi I acually have one with 10K miles or so on it.rotfl

The thing I have a fascination for is hot spark and the right timing curve.

I have heard the ol saying that a match can light a whole room of gas. That saying I always felt it was ignorant. Lets put the whole room under compression like say 180 psi? lol. The electricity fights and looks elswhere to go to ground in this condition. Think about the insulation etc that goes into all those connections.

In high school we had a little plexi-glass box built for testing distributers and spark plugs. This box could be hooked up to 110 a/c for spark or anything else conventional. Then shop air ''the kind for air tools etc'' would be connected air pressure could be read from a gauge as we went along.

The fun part of this was whatching crappy brands or plain wore out spark plugs simply stop sparking as the air pressure reach 200 PSI! Was dang neet to see as a young adult.

Timing curve is just as important to me too.


I have worked on RV's the kind you go camping in etc. All the way up to the big bus's. They all have a common Appliance that uses a pizzo for ignition on the stove burners. Somtimes these burners don't ignite no matter clicka clika. Funny thing tho I see a spark everytime. It is even blues in color.....

What is it then?? The fix for this is simple really. When the porcelain was assembled, they press it though a tiny metal ring used to mount this right at the burner. Somtimes from the factory there is a tiny coating of zinc on the porcelain. I clean them up with emery cloth. Those burners light up flawlessly after this. The funny thing is I always see a blue spark?? HuH lol.;)

Back to the engines. I run a Pulstar plug on my none chinese engines. It's my italian 14,000 rpm ones. One the dang thing is over carburated and will soot up in no time without that plug.
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
7,266
1,797
113
Los Angeles, CA.
Sorry guys... Like I said before, These tests aren't to bash or trash anyone... I'm only doing them so the world can finally have some kind of proof of how these different CDIs perform in real tests against each other.

Not a single manufacturer has ever provided us with any documented 'head to head' testing that theirs actually performs better than the others! (Just years & years of endless talk like you're reading from them (& their friends) above). :(

Of all the CDIs that I tested, the $19 gas Bike CDI made my race bike run the fastest... So I used it at the last big race & I won 3rd place in the Expert 2-stroke class... Which was very good considering that my bike had the wrong gearing, I'm way over weight & I'm not the smoothest racer. ;)

I'd also like to add that the 1st & 2nd place winners both used stock 'black box' chinese CDIs!! (They're just way better racers than I am)! :rolleyes:
 
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YesImLDS

Member
Jun 29, 2013
960
12
18
Columbia, Missouri
I agree with you on that one. The thing is despite cheapness or not. In a racing competition if it lasts you the race it's done it's job. Talking about quality or not some dragsters despite being built off some of the best parts in the industry are rebuilt every time they go down the drag strip. Now what I am trying to get across here is that the performance over the quality is what he is going after here. Might be the cheapest part out there, but if it performs better...
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
7,266
1,797
113
Los Angeles, CA.
I agree with you on that one. The thing is despite cheapness or not. In a racing competition if it lasts you the race it's done it's job. Talking about quality or not some dragsters despite being built off some of the best parts in the industry are rebuilt every time they go down the drag strip. Now what I am trying to get across here is that the performance over the quality is what he is going after here. Might be the cheapest part out there, but if it performs better...
That's a good point!!
I'm definitely not looking for 'performance over quality' here!
Quality (& longevity) are also very important... I'm just starting out with how they all perform, (& going from there).

If one does stop working over time?, I'll be very fair & post about that too. ;)
 

YesImLDS

Member
Jun 29, 2013
960
12
18
Columbia, Missouri
That's a good point!!
I'm definitely not looking for 'performance over quality' here!
Quality (& longevity) are also very important... I'm just starting out with how they all perform, (& going from there).

If one does stop working over time?, I'll be very fair & post about that too. ;)
Exactly. Now in my case I personally have the HD lightning and I only really put it on to replace the stock unit that is a couple years old with about 4k miles on it. Did I see a performance gain? I have no idea it was a fresh build, but is it a lot more reliable than my stock cdi with 4k miles on it should be? Sure it is.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Not that it matters now since this seems to be a bit dead here for a while, but...

I did some testing myself with multiple CDI units a couple years back.

Stock "China black box CDI"

Rocket/"Bottle Rocket CDI"

HD's Lightening an mine is one that isn't filled with Epoxy...

I was trying to reach my goal of 50 MPH on a bike with 24" wheels and a 30T rear sprocket and a Puch Hi Hi 70cc head, Dax RT carb and modified stock kit exhaust pipe.

My results were 52mph with China "Black Box CDI"

48mph with HD's Lightening and low 40's mph with Bottle Rocket unit.

I didn't do any voltage testing like VMB is doing which I think is a great idea that many of us will enjoy reading about.

I will say that that this last year I have had one Stock CDI burn out and it actually fried two different mags before I figured out what was going on, but other than the stock units have always do a fine job for me and even though I have no issue with the HD's Lightening CDI it didn't add any performance to my fastest bike over the stock unit, but I actually run the HD's Lightening unit on that bike now with a different engine since I cooked the top end of my goal setting engine not long after the mph testing.

I cant complain at all about the HD's lightening unit when it comes to reliability because this unit has held up good for a long time, an early version I got from Dan died with less than 15 miles on it but it was in the early stages of his project and he told me he was making changes and he sent me the one I have now as a replacement and it has been bullet proof.

The cost of the HD's is a good bit more than a kit CDI which I completely understand, if someone just wants a custom unit with separate coil and doesn't mind spending the extra $'s I would personally recommend the HD's Lightening CDI since I know they're made well and with good components.

BUT.... with all this said, I have to be honest also and say that if you have a basically stock engine or even a moderately modified engine and you think you will get a serious mph increase or felt seat of the pants power increase with any of the aftermarket CDI's over the stock unit, you will be disappointed because my experience was that although the custom units work just fine, I got my highest top speeds with a kit CDI.

I have nothing against Dan/huffyDavidson, Fed, VMB, Jake the maker of the Rocket unit or anyone else for that matter, but I will be honest about what my results were when I wanted to find out what my bike would do with each of the units I tested.

All test were done on the same day just minutes apart, same road, same fuel mix, nothing was changed accept the CDI unit.

I ran the stoc box first and GPS'd 50.3mph, I then tried the Rocket unit and was very disappointed with only low 40'smph, I then hooked up the HD's unit and hit 48mph, I then hooked the stock unit back up which by the way was a kit CDI I had got from BGF on ebay and that is when I hit my all time person top speed of 52.0mph running a Dax 40mm stroke lower, Puch head, RT carb, Modified stock pipe, modified piston and good clean enlarged ports in the jug and two base gaskets between jug and case.

I haven't used any of the newer CDI units that have been mentioned here, but for me either a stock box or the HD's lightening unit would be the only two I'd probably recommend to anyone since they have both proven to be good performers for me.

Peace
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
7,266
1,797
113
Los Angeles, CA.
I have to concur with you guys... The stock 'black box' CDI is probably the best choice for performance & reliability on 99% of the bikes out there.

The aftermarket CDIs retard the timing a lot & work better with extemely modified engines with large motorcycle expansion chambers.

Keep in mind what I said earlier about the #1 & #2 guys who beat me at the last big race were using the stock 'black box' CDIs! ;)
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Thank you VMB for all your effort to bring this honest and useful info to us the way you have in a very nice straight forward way.

There has been so much argument and mud slinging on here on this topic of the last few years and that is why I purchased multiple units to test them for myself on one single bike that had no changes accept the cdi swaps so I could see if there were an6 seat of the pants differences noticed and if I would see top speed change on same road, same day exact same conditions.

My results were clear to me immediately, all the cdi units with a timing retard ran fine but I lost top speed performance with every one of them, as soon as I would hook the stock unit back up my top speed would come back up as much as 6mph in a couple cases and the only unit that has provided comparible top speeds has been the HDs Lightening that Dan sent me as a replacement of the first Jaguar type unit I got from him that went out on me.

I have no issue with many of the after market parts like the cdi units, but it would sure be nice if everyone would be honest with there adds and not make all the inflated claims about big power and faster top speeds when the fact is they just simply dont deliver on those things.

Stock cdi units will provide more speed and overall power potential for these engines than 99% of the CG builds will ever be able to achieve for the owners of them.
 

jughead72

New Member
Jun 25, 2015
4
0
0
tovey il.
im new to motor bikeing but I have been around a lots of performance vehicles. the question I have is any of these cdi units help to reduce engine vibrations? did anyone measure the resistance of the plug wire? on my performance auto builds I always use msd components ? can u change the plug wire on these cdi units? I would like to run a msd wire on mine if I could. I have a raw racer kit I bought from kings with there high compression head on it from there kit. im just looking to get all I can out of it. just like any other motorhead.
 

ejbabin

New Member
Dec 8, 2014
14
0
0
Louisiana
Hey guys I'm considering getting the "super charger" cdi from gas bike. What ngk spark plug should i use with an angle fire head and a flex pipe muffler with an expansion chamber?
 

Pablo

Master Bike Builder & Forum Sponsor
Dec 28, 2007
3,696
33
48
Duvall, WA PNW
www.sickbikeparts.com
I appreciate this test. We sell both the Jag and Lightning and yes we have marketing spiel on our site. So of course anything I write is biased. Take it for what it is. But know this, I've been living in electric motorbicycling the last whatever years. I missed the smell of burning castor oil in the morning.

Firstly CDI's are not miracle products. If your engine runs terribly for various reasons, it will continue to run like junk regardless what type of CDI you slap on. If your engine is mechanically unbalanced a CDI will not "cure" that.

What I personally have seen and felt, on the three engines (decently tuned with SBP pipe) I have but BOTH Jag and Lightning on, they all start easier. Same plug, everything the same. Same (or withing a few degrees) morning temperature. Probably better coil.

0-30 mph is close, no stumbling on any.

At 40mph+ seems like both the Jag and particularly Lightning have some pull left.

I guess my message is if you have a tuned pipe, dialed your fuel in, opened up your ports and manifolds, bumped compression, a CDI is not a crazy investment. Stock engine? Do the other mods first.
 

bradnbikes

New Member
Jan 23, 2016
4
0
1
minneapolis
I am curious if anyone has tried a resistor spark plug wire or resistor plug .
I am going to try using resistor plug wire on my new 4.5 hp motor from Gasbike.net
I am an automotive tech and thought resistor wires make a hotter more intense spark
(I cant verify that it is true about the hotter spark)

If someone can tell me it drives the coil too hard or if someone has tried it and it didn't work let me know

Below is a link to page to MSD ignition CDI for race cars ,, may not pertain to what we have here with the Gasbikes on page 11 they talk about not using solid core wires with their ignition systems , not sure why... but the the electronic engineers here may be able to explain that and why it does not apply to gas bikes ignition

http://www.msdignition.com/uploadedFiles/MSDIgnitioncom/Support/WDTN_pn9615.pdf
 
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2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
Resistance is not what you want to add to these ignition systems. Use a plug wire with a metallic, preferably copper core, and a non-resistor plug.

Not sure about your theory that resistance wire will provide a "hotter more intense spark".
Can you provide any proof of that?

Tom
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
Ignition systems for automotive applications today must take into account the sensitive electronics (computers) that control the critical functions of current cars. The old style ignition systems were notorious for causing electrical interference with solid state devices as far back as the 60s when solid core ignition wires would produce static in radio reception. TVRS wire was introduced to combat the problem.

As the electronics evolved into what we see today ignition systems have had to be tailored to work with them without causing RF, or radio frequency problems. Even race cars now utilize sophisticated electronic/computerized systems that would be adversely affected by old style ignitions.
This is why you'll see the makers of aftermarket, high performance ignition touting the benefits of resistance wire and plugs.

The Chinese 2 stroke engine designed to be mounted on a bicycle doesn't need to worry about electrical interference but wants/needs all the voltage it can get to the spark plug. That means the least amount of resistance in the high voltage circuit. Some problems have been reported with electronic bicycle speedometers/computers and those issues have been discussed here at length with ways around it and fixes.

I maintain that using wire and plugs with the least resistance will result in better performance from the Chinese 2 stroke. Also don't be taken in by the claims that an iridium plug will increase performance. If you're looking at putting a hundred thousand miles on your engine before a plug change and want to waste money then go for the iridium. If not stick with a $2.00 NGK B-6 plug. Also throw away the kit supplied plastic spark plug boot and replace it with a good automotive quality boot.

Tom
 

exokinetic

New Member
Mar 18, 2016
108
4
0
Lake Forest, CA
Thank you Venice Motor Bikes for this valuable information!


This proves to me at least what I had already suspected.

The "upgrade" CDI's provide retarded ignition curves (compared to stock). And this is exactly what I want for my extremely high compression race engine builds.

It also allows me to choose the CDI with the most retarded curve, incredibly useful information, can't thank you enough!
 

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
0
memphis Tn
I'm currently using the Screaming Roo coil/CDI combo.
Feels just like a Lightning, but has heavier coil windings with better insulation and a heavier CDI box to handle the added voltage. Still has the better low end noted from the Lightning.
Not looking for more power, but more reliability.
Almost 2 years and I have not even cleaned the plug. :)
 

BikeMan2

New Member
May 23, 2016
2
0
1
IL
I have bought 2 of the High Performance Super Charge CDI for 48cc/66cc/80cc for both of my bikes and I love them over stock my Engines run much smoother in all RPM and they seem to run much cooler and fire way better. I have rode with them for well over 1000 miles and will not buy any other CDI unit.
 
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