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Old 09-10-2013, 07:43 AM
motorized kodiak motorized kodiak is offline
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Join Date: Aug 2013
Location: australia
Posts: 105
Default up graded cdi

hey guys, ive seen these up graded cdis go for 75$!,thats pretty costly, but are they worth it, what do they do to make you bike work better? thanks
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Old 09-10-2013, 01:27 PM
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maniac57 maniac57 is offline
Old, Fat, and still faster than you
Join Date: Oct 2011
Location: memphis Tn
Posts: 4,486
Default Re: up graded cdi

Some people swear by them, but the general consensus is that they do very little for performance on 99% of engines.
I'm sticking with the kit part until I see something concrete.
If more is better, then too much is just enough.
If you can't afford it, build it yourself.
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Old 09-10-2013, 02:54 PM
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Wild Bill Wild Bill is offline
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Join Date: Jan 2013
Location: Camarillo So. Cal.
Posts: 475
Default Re: up graded cdi

I put the Jaguar CDI on my china girl bike after doing some test runs with the stock ignition going both ways on the same stretch of road to eliminate the wind or breeze factor and possible road incline. Then I put on the Jag and picked up 2-3 mph and played around with the settings and the stock settings worked best. The difference was noticeable but not huge but 2-3 mph when your top speed is only around 35-40 its a nice gain.

But then a few weeks later someone said they didnt do anything and that people that race dont use them so since he was correct that people that race didnt use them I decided I better test it again, I want to get all I can from my bike and lying to my self isnt gonna make me any faster.

Then I mounted the stock coil next to the Jag and since I have quick connect plugs I went out to my test road and made several runs in each direction switching back and forth between the 2 ignitions and consistently saw the same 2-3 mph every time. I am using a digital speedo so I would get IIRC 41.2 mph and Im sure my speedo is consistent. I also retested the different settings on the Jag and found the same result, the stock setting was clearly the best setting.

One thing I cant say for sure is if the Jag cost acceleration to gain top end speed but it feels like acceleration is still the same with the Jag but Im using a shift kit so it wouldnt be so noticeable with the lower gears and up shifting as it would be with a single speed bike.

One thing to remember is that these chinese engines are very crude and the engine timing probably varies from one engine to another by large amounts in some cases. I am on my second engine and have retested both ignitions on the new engine with the same result as my first engine (both DAX F-80).
Its all fun and games until someone loses an eye, then its just fun!

Last edited by Wild Bill; 09-10-2013 at 03:03 PM.
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Old 09-11-2013, 04:01 AM
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Huffydavidson Huffydavidson is offline
Join Date: Jan 2012
Location: st.louis,mo.
Posts: 1,078
Default Re: up graded cdi

The thing JAG does is that , with the timing being retarded is that the engine a he!! of a lot LESS vibration. This means LESS STRESS on the bearing and in return your engine will last LONGER , run SMOOTHER and you'll get just a little better gas mileage. I have run the same testing as WB and my results were the same pretty much. I run with jumper A-1 in (24 degrees BTDC), and no B jumper at all.
I have built the Modified CDI & CR-80 coil set-up and had good results as well. They not over priced and I can say this because I know first hand. I've built them & run them . Two things I will not do, go back to stock CDI and never run any less than a DAX balanced bottom end.
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Old 09-11-2013, 11:42 AM
BonusParts BonusParts is offline
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Join Date: Nov 2012
Location: SE-PA
Posts: 168
Default Re: up graded cdi

Having purchased a Jaguar CDI and used on my bike the difference is extremely noticeable - ON A MODIFIED MOTOR. Well worth the money spent.

Things i noticed:

Better power overall
SIGNIFICANTLY REDUCED vibration throughout the powerband
improved fuel economy.

I am quite happy with the jaguar CDI. I also made quick connects for the system so i can switch CDI's quickly and easily.

IMO if you have raised compression and port work done its a must.
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