what CDI? Jaguar or HD Lightning?
- Thread starter mrfubs
- Start date
No question on that, get the HD Lightning.
The Jaguar CDI hurts top end performance which is why the racers
at Socal Motor Bicycle Racing events don't use them.
I would have to agree... the HD Lightning definitely outperforms the Jaguar at top end, Even Micheal admits he put too much timing retard into his Jagaur units but he still selld them that way.
I'll soon be experimenting with the Rocket CDI that's being sold on ebay now as well to see if it's any good or not... It's a brand new engine so I want to break it in really good before doing any real testing, but I'm pretty sure the HD Lightning will still come out on top.
I'll soon be experimenting with the Rocket CDI that's being sold on ebay now as well to see if it's any good or not... It's a brand new engine so I want to break it in really good before doing any real testing, but I'm pretty sure the HD Lightning will still come out on top.
Thanks guys that sums it up for me now Im pretty confident my new build will reach the 55mph mark no problem honestly. My last build reched 48 with a 36t sprocket non case reed with the junk cns carb. New bike will be 32t sprocket, case reed dellorto 21mm carb and crazy porting
The retard on the Jaguar is intended to reduce vibration by limiting revs
as far as my understanding goes. That may be why he has not changed it.
The HD Lightning is getting much better reviews.
I'm waiting on one myself in fact!
as far as my understanding goes. That may be why he has not changed it.The HD Lightning is getting much better reviews.
I'm waiting on one myself in fact!
It reduces the pressure on the rod from the fuel mix explosion by retarding. At high revolutions the vibrations and repeated stress on your rod and bearings is quite hard on the bike. Using a properly tuned jag CDI will reduce them, until (depending on your settings) at extremely high RPM's the spark actually fires AFTER the piston begins to descend. This means you're losing efficiency because the piston's already on its way down and the pressure has next to no effect on the piston. It's like pushing your kid on a swing, once you get them going so high, there comes a point where your pushing becomes moot as they come flying by you. this greatly reduces stress on the motor, whose cheap factory bearings are already a source of many woes. But it also means your top end will suffer. The solution? tune it differently... not terribly difficult. Make it a shallower curve and set the starting point advanced by 4 degrees. maximum power. It has very little effect on vibrations, though. Your piston weight and/or crank balance will change that. But fun fact, my 66cc piston weighs 96 grams (12 less than stock if memory serves), and vibrations are... well they're well under control. If you've run a 66cc upward of 45km/h, you know how ridiculous those vibes get (hands go numb, feels like they lock in place). My bike, because the piston is significantly lighter, its very smooth from the beginning, and at around 60km/hr (I run a 36T sprocket) the motor reaches harmony and the whole thing runs silky smooth, not a single vibration except from the road.The retard on the Jaguar is intended to reduce vibration by limiting revs
The HD Lightning is getting much better reviews.
I'm waiting on one myself in fact!
The included CDI will always produce the most power (provided your magnet is aligned properly), as the advance is timed so that when the piston reaches TDC, the fuel mix is at the maximum pressure to push the piston back down most effectively every rev. But this high pressure every stroke, even at extremely high RPM is a lot of repeated stress on your internals, your standard engine cranks 140psi (I think) out of the box, and thats just sheer air compression (in 2 strokes, this pressure rises with RPM), that's not even the actual burn.
I havent even heard of the lightning CDI aside from someone wanted to make another "high performance" CDI. And from the looks of the thread, he simply changed out one capacitor for a larger one in the jaguar design.
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There are a lot of us who will take apart a CDI and change out the caps or put in a potentiometer to get the most out of our engines as well as address the real vibration issue of the piston assembly being way too heavy for revs past about 6k rpm... There's no secret there...
When we recommend a "best CDI" to someone, it's the one that they can bolt on and go without toying with. The stock CDI does make good power but not so good once we raise our compression ratios thru the roof combined with a tuned pipe and better intake, that's a recipe for detonation and disaster. The solution next is to either make a better CDI that we can tune to match our engine's new specs or to buy one already made. Most of us want the one that's going to make the most power and just swap out the bearings when they get too loose and everyone who races these things know the wrong ignition timing won't get them in the winner's circle so they're also going to buy the one they can bolt on and go without blowing their engine half way thru the race.
Of the aftermarket CDI units available, there are really just 2 proven choices with one being the Jaguar and the other being the HD lightning. The Jag won't bring you home any trophies but with it's mild manners, people buy them to smooth out their engines for putting around the neighborhood, but everyone else who wants the best performance there's the HD Lightning.
The HD lightning was well thought out and built for max performance while still backing off the top end timing just enough to keep an engine alive, it can be installed and it's ready to run, and it will win races. This has been proven several times over.
Now there is another CDI unit on the market and not many of us have this one yet, I got one but hadn't tested it out yet, it's a very simple build and just like the other 2, it can be modified by the right tuners. Once this one is tested, I'll report my results and decide where to rank it. My guess right now is it'll make more power than the Jag, but the HD Lightning will still be on top, but that's just a guess... for now. Others in here have bought the same one and haven't reported back yet.
When it comes to someone asking which CDI is best, yes, they all can be tailored to be the best, but when someone is asking, we have to assume they want to order it, bolt it on, and go riding, so it's all about which one is already tuned to perform and that's why my opinion still stands to say the HD Lightning is the superior product. If anyone buys any of these and changes the timing whether they use a different cap or potentiometer, then that unit can be tuned to out perform the others, but right out of the box and onto your bike, the HD Lightning is still the best.
When we recommend a "best CDI" to someone, it's the one that they can bolt on and go without toying with. The stock CDI does make good power but not so good once we raise our compression ratios thru the roof combined with a tuned pipe and better intake, that's a recipe for detonation and disaster. The solution next is to either make a better CDI that we can tune to match our engine's new specs or to buy one already made. Most of us want the one that's going to make the most power and just swap out the bearings when they get too loose and everyone who races these things know the wrong ignition timing won't get them in the winner's circle so they're also going to buy the one they can bolt on and go without blowing their engine half way thru the race.
Of the aftermarket CDI units available, there are really just 2 proven choices with one being the Jaguar and the other being the HD lightning. The Jag won't bring you home any trophies but with it's mild manners, people buy them to smooth out their engines for putting around the neighborhood, but everyone else who wants the best performance there's the HD Lightning.
The HD lightning was well thought out and built for max performance while still backing off the top end timing just enough to keep an engine alive, it can be installed and it's ready to run, and it will win races. This has been proven several times over.
Now there is another CDI unit on the market and not many of us have this one yet, I got one but hadn't tested it out yet, it's a very simple build and just like the other 2, it can be modified by the right tuners. Once this one is tested, I'll report my results and decide where to rank it. My guess right now is it'll make more power than the Jag, but the HD Lightning will still be on top, but that's just a guess... for now. Others in here have bought the same one and haven't reported back yet.
When it comes to someone asking which CDI is best, yes, they all can be tailored to be the best, but when someone is asking, we have to assume they want to order it, bolt it on, and go riding, so it's all about which one is already tuned to perform and that's why my opinion still stands to say the HD Lightning is the superior product. If anyone buys any of these and changes the timing whether they use a different cap or potentiometer, then that unit can be tuned to out perform the others, but right out of the box and onto your bike, the HD Lightning is still the best.
Well you can read my post in ignition about my results with the HD Lightning CDI. I'm a notorious skeptic and I'm sold!
Can the HD Lightning be Modified?
My understanding was that it had been sealed in Resin.
I have three running bikes now in different states of tune, all with fresh motors, as well as a choice of magnets offering different initial timing settings.
I have not even tested my Rocket CDI yet nor modified it. I have been waiting to get my 'Goat' running, which is the most highly modified of my Motors, and a Day to my self (two young children and work) to do a proper testing. So far have been swapping magnets and found too much initial advance seems to be detrimental to overall performance, but have not even got to putting a timing light to the motors. They all have Tacos and all 3 motors seem to top out around 8500 RPM with similar exhaust durations of around 150 Deg.
I hope to give all a reasonably detailed evaluation, But have read that the ideal setting is around 20 deg advance. And can see that the 'variety' of initial advance settings due to 'sloppy' manufacturing will give different results for different engines/riders.
My understanding was that it had been sealed in Resin.
I have three running bikes now in different states of tune, all with fresh motors, as well as a choice of magnets offering different initial timing settings.
I have not even tested my Rocket CDI yet nor modified it. I have been waiting to get my 'Goat' running, which is the most highly modified of my Motors, and a Day to my self (two young children and work) to do a proper testing. So far have been swapping magnets and found too much initial advance seems to be detrimental to overall performance, but have not even got to putting a timing light to the motors. They all have Tacos and all 3 motors seem to top out around 8500 RPM with similar exhaust durations of around 150 Deg.
I hope to give all a reasonably detailed evaluation, But have read that the ideal setting is around 20 deg advance. And can see that the 'variety' of initial advance settings due to 'sloppy' manufacturing will give different results for different engines/riders.
My understanding is it is potted. But this is no issue to me as I have no desire to mess about with electronic innards.
All I know about electronics is how to let all the smoke out.
All I know about electronics is how to let all the smoke out.
As far as the cdi selection goes im leaning far twords the lightning. Iv see the rocket cdi thats cased in a pill bottle but hey the builder claims his cdi is rated for 10500rpm and for 40 bucks ot.may be worth a shot before i try the lightning. There was a lad to tested the rocket cdi compared to the stock and ran his route 2 times to be sure of equil testing. He topped out at 36mph with the stock cdi and 36 with the rocket cdi. He claimed smoother idle and easier start up so with all of that said ill pay another 40 for the lightning.
Running 13:1 comp and a strait pipe on a drag bike I made that tops out at 42mph on a 44t rear ! I am running the stock cdi and with wide open intake ports and a tall exhaust port I can tell you that eevn with 93oct mixed with 10%zylene for around 96oct on 13:1 comp I still got detonation at around 8,000 rpms with the stock cdi.... I actuall had to pill ofc the magneto with a puller and go through my parts box and find 3 spares and compare them all to find one with the most retard. It ended up being a grubee gt5 magneto that had a few deg les advance so I predded,it on and rebolted it up and ran,that and the detonation left but the vibes were still there and it now sputters at 9,500 or over lol
I may have to pick up an hd lightning cdi and run a lil bit more advancw on the magneto to get the most of this motor
I may have to pick up an hd lightning cdi and run a lil bit more advancw on the magneto to get the most of this motor
Advance is going to get you more detonation, you want less (more retard), at least as far as I recall regarding turbo (high compression) setups. I wish I knew how to key my own magneto, what I saw for the adjustable magnet was really confusing. Advance is going to net you maximum pressure at TDC and net you maximum power, but of course high pressures as the piston is coming up means the rest of the gas can be ignited (you want a full burn by 40 degrees ATDC IIRC).
Thats what I did was go through all 4 of my magnetos and find one from a grubee that was the mpat retarded and runn it ... The detonation left but it now sputters up around 9,000 qhen she is wide open like the spark will not jump the gap at those rpms under 13:1 comp ... I was thinking to go to a stock timing advance with theost acurate magneto and run a hd lightning and I hope that will get me up to 10,000 rpm and still have a poerful spark under the comp I am running a nkg b6hix iriduim plug
Anyone running an a CDI with increased advanced timing should watch the head temperature. If elevated, you may benefit from an NGK in the 8 or 7 heat series range. Changing from a 5 to an 8 made a huge difference in one of our test mules. I know the NGK Iridium only comes in the 7 heat range, so if you have a 6, look at the 7.
Not true Pablo, I've got a pair of 9s and 10s the coldest ngk makes. CALLUM UP!!!! Remember what I'm running? But true I think EVERYONE should run a temp gauge. It save your little girls life.
Ok that does sound good ... So I am now running a tep guage on the plug threads.. What is your recomended operating tep ? And what is a good max temp . ? And at what temp do you consider it overheating? r is that all dependant on the motor and fuel mix ratio in question?
I run damn near 9500 rpm for long bursts going from intersection to intersection and i run it close to 13:1 comp with 93oct mix with 10% xylene at a 32:1 mix .
Would you say 350 deg would be a good max tep and 280 a good running temp
the champion #6 plug and the #7hix nkg plug seem to do the best job under those conditions
So are you calling me a liar?
~35°F drop - which BTW allowed more RPM/top end power and smoothed the engine a bit - is not something I would just make up. Sure if you want to go 9+, fine for a hot day racing. But the Iridium only come in 7 max. Thanks.
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I don't call names, however I do state facts.
NGK IRIDIUM/IX
BR10HIX
PART#6692
Fell free to reply
No thank you kind sir LMAO
NGK IRIDIUM/IX
BR10HIX
PART#6692
Fell free to reply
No thank you kind sir LMAO
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You are correct on the BR10HIX! (and BR9HIX).
But they don't make a BPR9HIX or BPR10HIX, which is what I was talking about as far as plugs and what we sell. (look it up) I have not tried the non-P version.....hmm...but I do see they now sell a BPR8HIX (they didn't used to have that 8, so that is cool)
P= Projecting Insulator Type
But they don't make a BPR9HIX or BPR10HIX, which is what I was talking about as far as plugs and what we sell. (look it up) I have not tried the non-P version.....hmm...but I do see they now sell a BPR8HIX (they didn't used to have that 8, so that is cool)
P= Projecting Insulator Type
Now that where talking about plugs what plug u all think i should go with? Fred made me a 6.5cc head for my case reed motor maybe the 8 heat range? i will be running 110oct currently going to use no head gasket with the jug decked squish clearence is .032 thou
