After Market CDI ?

I'd like one.
Being able to give a bit more retard curve on a bike that pings above 8000 would be great.
Fitting a larger head unfortunately not an option on this bike but would be even better.

Hello Duane, I have the HD Lightening cdi running on your gen IV motor. I noticed a big difference using this cdi over the original. The low rpm performance is vastly improved. I can now run my bike at around 2200rpm without it sputtering or lugging. I had a difficult time tuning my nt carb because I had very inconsistent plug chops. After running the new cdi I've noticed that my plug chops are consistent every time and I was able to tune my motor more easily. The plugs went from wet dark brown to a perfect dry chocolate brown without touching the needle or changing jets. I think this is due to the stronger spark. Overall I think it's a good investment

Thank you Chris8686, I appreciate your input on this CDI. I have tried posting a couple ways now about CDI's, but not much response. Your down and dirty review is great.

Love to hear more about peoples CDI experiences.

Duane Ive been running the Lightning since HuffyD started making them. All I can say is WOW over stock there is no comparison it is a noticeable increase in power all across the rpm band.

Removed by me.... I no longer support lightening CDI.

I will no longer promote or purchase any product from vendors that I think are unethical.

thatsdax said:

Hi.. I am looking for feed back from those using the After Market CDI's. Mainly the Lightning and the Dragonfly. Are they worth the money? What is it you like about them? Passive or Active timing curves? Or just a hotter spark ? Any feed back good or bad would be of interest. Thanks..

Click to expand...

Hi Duane, I have both the Jaguar(pre Dragonfly) and the HD Lighning. The Jag has 3 settings and the only one that works is the default setting(No jumper).With the Jag I picked up 2-3mph which on the China Girl engines is a nice gain. Both the Jag and the HD have a hotter coil and a timing curve that retards the top end for more rpms and the HD has a different low end timing but Im not sure of the exact amount.

I just put on the HD ignition but at the same time I also put on a Fred Head so Im not sure how much the CDI gave me by itself but I picked up 5mph and I believe it would have been more of a gain but my gearing is what kept me from getting more. I would say hands down the HD CDI is the best! The top end is much better than I have ever had out of a China Girl(Its the balanced crank F-80 I got from you) and the HD seems to have a better bottom end power also. I went from 40mph before the CDI and head changes to 45mph and Im sure with more tuning, more gearing and break in time it will get a little faster(still just 1 gallon fuel on it).

I swear by them!!

@ ThatsDax

Hello,

I have 3 CDI's. I have used 2 thus far.

My engine to start was a grubee 66cc. hi comp, ported etc etc.
Ran 43.62 via GPS on the stock cdi w/ an accel wire and ngk plug
using the 2 jumper Jaguar system - everything else UNCHANGED i noticed:

Max speed went DOWN to 40.67mph
WAY less vibration ALL the time.
Much improved low end torque
much snappier response and quicker starting
My engine DOES NOT rev past 7800-8000rpm under any circumstance.

NOW. I used this jaguar cdi on my Fred motor (fully done up) And it STILL wont hit over 8000rpm.

I purchased a lightning cdi setup after talking to Fred about my frustration, i have not run it yet. I will report back with my findings when i have them!


Other than its designed RPM limiter (due to spark retard in high rpm) its much smoother in operation and absolutely the best way to go for a commuter motorized bicycle

BonusParts said:

Other than its designed RPM limiter (due to spark retard in high rpm) its much smoother in operation and absolutely the best way to go for a commuter motorized bicycle

Click to expand...

It seems backwards I know but a 2 stroke actually gains RPM when you retard the timing on the top end, just the opposite of a 4 stroke.
Both the Jag and the Lightning actually work and do not limit rpm, they will gain it, you have something else limiting your rpm and top speed(You have ported but have you cut the piston skirt? I would think that would limit rpm no mater what changes you make. Also when you ported if you changed the port height too much that could limit it.). I only saw a top end gain in the Jag using the default setting (No jumper) and no noticeable change in the other settings beyond the stock ignition and the Lightning just works out of the box without having to try different settings.
I could post several links to verify that a 2 stroke needs a timing retarded curve but theres no need to do more than one.....



http://justyamahard350.com/articles/eric.htm


From the link:
AFFECTS OF THE IGNITION TIMING

Here is how changes in the static ignition timing affects the power band of a Japanese dirt bike. Advancing the timing will make the power band hit harder in the mid range but fall flat on top end. Advancing the timing gives the flame front in the combustion chamber, adequate time to travel across the chamber to form a great pressure rise. The rapid pressure rise contributes to a power band's "Hit". In some cases the pressure rise can be so great that it causes an audible pinging noise from the engine. As the engine rpm increases, the pressure in the cylinder becomes so great that pumping losses occur to the piston. That is why engines with too much spark advance or too high of a compression ratio, run flat at high rpm.

Retarding the timing will make the power band smoother in the mid-range and give more top end over rev. When the spark fires closer to TDC, the pressure rise in the cylinder isn't as great. The emphasis is on gaining more degrees of retard at high rpm. This causes a shift of the heat from the cylinder to the pipe. This can prevent the piston from melting at high rpm, but the biggest benefit is how the heat affects the tuning in the pipe. When the temperature rises, the velocity of the waves in the pipe increases. At high rpm this can cause a closer synchronization between the returning compression wave and the piston speed. This effectively extends the rpm peak of the pipe.



http://www.f1technical.net/forum/viewtopic.php?f=5&t=10315

I dont car what science says. End of the day the early jaguar is too retarded past 7500rpm. I contacted the maker michael and he said the same. They do NOT go over 8000rpm on the early jumper style jag. TOO much retard.

So whatever want to post is fine but in the real world it went slower and the maker agreed it was due to the curve. His new unit accomodates for that and has a longer curve for high rpm.

So
You were saying?

When you said due to the retarded timing I thought you meant that top end timing should be advanced and not retarded on the top end like a four stroke. If you meant that it is just retarded too far on the jag then I misunderstood, my bad. I picked up 3mph with it in the default setting so it must not be too far for me.

I tried to be clear.

Lemme rephrase.

The EARLY jumper style jaguar cdi does this: performs AWESOME low and midrange, snappy as ****.... BUT, when you get to about 8k rpm it dies out, the curve retards too early for my engine configuration.

I am hoping the HD lightning fixes it because all my reading suggests that it is a tighter tolerance clone of the jaguar with a bigger timing bell curve.

Post removed by map.... no longer supporting Lightening CDI

And will not discuss why in open forum, if you have to know PM me.

Map - On my grubee the vibrations were terrible using a stock CDI. the jaguar did smooth that out - but like i said with its timing curve engine RPM into the 8k range just wasnt happening.

I have a lightning now, havent tested it yet but its going on a fully build PK-80, ported, cut on piston, fred head, balanced stuffed etc etc.

I may modify my jaguar with a different capacitor. Michael emailed me back after I asked him what i could do about 8000rpm and higher. He gave me 2 options for capacitors depending on my intentions.

If I try that, will let you all know what happens in a head to head on my bike vs the lightning.

Removed by me.....
Map

mapbike said:

...the lightening has already been proven to out rev and produce better overall poweron highly modified engines at the race track by people that are top notch engine builders, that settles it for me but again this difference was noticed on race built engines and may only provide small advantages on a bone stock engine that has nothing upgraded on it...

Click to expand...

Map, have to totally agree with you on this. For 99.9% of stock engine users, the stock CDI does an adequate for the job. If you have a highly modified engine, then that is a different story.

The original CDI was manufactured to run on a 48cc engine. So if your trying to run the stock CDI on a heavily modified race engine, your at least 2 generations past the stock CDI. Heavily modify any engine and the ignition system isn't going to be adequate. Your pumping more air/fuel at a higher compression ratio.

I haven't seen any claims based on empirical evidence, such as test runs on a dynomometer - just subjective seat of pants reporting.

If easy engine starting is what your after, why not get a intake manifold with a boost port and squirt some starting fluid into the carburetor. Some members with medical problems have reported using starting fluid to start their engines and haven't reported any damage or engine problems.

Sometimes people run too rich of a mixture, in-properly use the choke or fail to use the tickler on the carburetor that makes starting more difficult. Or it's a possibility they're still using the stock plug and plug wires. Or how many have a high compression head. There are many reasons why the engine may be hard to start. It may not be the CDI.

A key switch is a nice theft deterrent, but how many members have reported hearing someone start their bike and take off with it. Most are probably silent walk offs. Most thieves probably know that you can buy a stock CDI for $10 off Ebay - Your term: "gizmo"

An ideal CDI would be one that has two pickups; one for low RPMs and another for higher RPMs - just as ideal as a carburetor with a slow and fast jets. This is due to the inherent nature of the 2 engine power band. Again, it would only be cost beneficial to someone with a modified engine or someone who's got too much money - but then again, there are those who buy higher octane gasoline even though their engines run just as good on a lower octane gasoline. To each their own.

Thanks for your honest evaluation,

Chris
AKA: BigBlue

Disclaimer: I don't own a HD Lightening CDI and/or a Jaguar CDI. I have no professional or casual association with the developers or owners of the HD lightening CDI, Jaguar CDI or any other bicycle engine manufacture and or distributor, or the owner and or moderators of this forum. My opinions are my own and I haven't been paid directly or indirectly by the developers and/or owners of the HD Lightening CDI, Jaguar CDI, and or any other bicycle engine manufacture and or distributor, or the owner and or moderators of this forum. My opinions are not an endorsement of any product mentioned in this post.

Removed by me
Map