Cdi

[blue_blooded]

hey, as you can all prob tell im new 2 this game after jus buying my first bike an atomik reign 140cc iv heard alot about these DCI thingys and was jus wondering if some one could elaberate on them a bit for me please. Cheers

 

[M@rkay]

they just make ur bike have a bigger rev line. i guy i know put a race cdi on a dhz 1400cc engine and it didnt give him any more power or responsiveness. they dont really do much

 

[agressive1]

Ive heard goods and bads about them. As in no power gain or noticeable power gain.

Some say they give you much more lower end.

 

[I_THUMP]

Read this thread

http://www.miniriders.com.au/forum/tech-reviews/14945-ebay-race-cdi-rev-box.html

 

[themountain]

use the searchfunction...there are trillions of post about it...and basicly all say : spare the cash for better things!!..they do NOTHING

 

[ducar.r.spec]

guys ur mixed up here
he wants to know about cdi's in general i think

 

[themountain]

well...you got a point there!!....so here it comes:
The CDI itself is really just an amplifying switch with time delay. It sits there storing up electricity in a capacitor (ie the "C" in "CDI"), then the pulse sensor spikes the input, the CDI waits a small amount of time and then puts the burst of electiricity it stored into the coil. That small amount of time represents the advance curve of an engine, ie at idle an engine may need 10 degrees advance but at full revs it may need 40 degrees advance. By delaying the signal and having the pulse sensor in the right place, the CDI can make sure the engine is getting the right advance curve.

cheers

 

[1fifty1wheel]

they do change the ignition curve for the engine, but in a motor of 140cc you won't (most who do just expect/believe it) notice the difference (most who do just expect/believe it), many people barely notice the difference in car engines after remapping the ignition curve.
they also (most) remove the rev limiter.
a few mates have noticed a decrease in fouling spark plugs, (could be coincidental) but fouling plugs generally caused elsewhere

 

[red_demon24]

i know some guys tend to say they dont make any difference, but i can notice the difference.
i find that with the racing cdi the bike revs harder and has more acceleration
but all bikes are different and we all ride diferentley so if ya have a spear 20 bucks lying around and you bought one you might be able to tell the difference in it you cant buy much else with 20 bucks these days anyways apart from a pair of grips or sumthin so....

 

[themountain]

i know some guys tend to say they dont make any difference, but i can notice the difference.
i find that with the racing cdi the bike revs harder and has more acceleration
but all bikes are different .....QUOTE]

then your carb is not dialed in correctly!!