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Discussion Starter · #1 ·
Hi guys,

before you shoot me down, yes I did search but couldn't find any thread (other than a carby jetting thread) with the word derestricted in it.

so, the question is has anyone tried one of the so called derestriced CDI's available on ebay (about $80 or so)?

they claim all sorts of wonderful things, but i'm mainly interested if they release any power on their own. I can't imagine the MC22 is that restricted in stock form as 45hp from it's little 250cc is a fairly decent state of tune, on top of that just changing the CDI without re-jetting the carbs or somehow getting the thing to breathe better is not going to add much power, but I'm still curious to see if anyone has tried one and got positive results.
 

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I can't remember off the top of my head seeing any threads about it being done, but someone may pop in.
I have seen one of these for around $55 for a postie bike and wondered if it was worth it, hmmm, dunno.
 

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Discussion Starter · #6 ·
yeah I would expect as much. how on earth it would give more power without any alteration to the air fuel ratio is beyond me. it would only be possible if the thing already had a super weak spark that was costing power due to incomplete combustion and then this new CDI improved it somehow. and if that were the case the thing would be running like a dog. they do love to boast that it will do everything from more power to bigger e-peen. but it's typical ebay bullshit.

perhaps in conjunction with some re-jetting of the carbs, a higher flowing exhaust and some air intake mods it might do something..... still doubtful.[hr]
just for a laugh this is their claims:

1) unlimited horsepower
2) High Rev Limit
3) Speed Limiter Removed
4) Timing Curves Improved
5) Raised Spark Energy
6) Improves Throttle Response
7) Easier to Start

lol, I do like the sound of unlimited horsepower, though I'm not sure I'm capable of riding a MC22 with such power.
 

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Twist your frame, snap your chain and generally fuck yourself and everyone around you up i would assume. Increasing the rev limiter is a good way to make your screamer of an engine go BAHNG!
 

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it can improve performance without changing a/f mixture
if the ignition times are changed, it can definitely improve performance if there is potential for it[hr]
its a chinese cdi...you can figure out the rest
 

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Discussion Starter · #14 ·
viper33 said:
it can improve performance without changing a/f mixture
if the ignition times are changed, it can definitely improve performance if there is potential for it[hr]
its a chinese cdi...you can figure out the rest
yeah, I said that it can improve power but only if the current timing curve is less than optimal. I would have thought for the size of the jets, the cams etc that the timing curves set from the factory are pretty much optimal for the bike, to the point that screwing with them probably won't get any gains. on a lowly tuned bike sure, but on something like the MC22 which already squeezes 45hp from it's little 250cc then it's a big ask to improve that output by just altering the timing curve. I take your point though, it's a $60 chinese made CDI, I don't think anyone sane is expecting any miracle gains from it. I was just curious if anyone had tried one and what if any differences they noticed. it's possible if the factory timing was very conservative that a more aggressive curve could gain a few hp, but again I'd hazard a guess that the factory MC22 timing map is pretty much spot on. for the sake of $60 I might still try one out.
 

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i'd only ever buy one as a replacement case for an oem cdi or open it up just to see how it was made. other than that, i wouldnt even hook it up to my bike for fun since i have no idea how it will affect my engine, especially since you can only go off the claims made on their page, which have already been proven to be bullshit.

if it was HRC or from a reputable aftermarket brand, i'd think about it after some research, but its already been said that to get 45hp out of a 250cc engine says something about the tuning. just mark it up as another generic gadget from china and leave it at that. if youve got a another bike to guinea pig it, cool, but keep that shit away from your bike cos the risk to reward ratio is off the scale.
 

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Discussion Starter · #16 ·
yeah probably wise advice. tbh the speed limit on the MC22 doesn't really bother me as it's not like they are hurtling off into the sunset once you're approaching 180 anyway and I imagine even without the speed limiter it would struggle to get to 200km/h or so in 6th anyway. actually I wonder if being an aus delivered model it doesn't have the 180km/h limiter anyway? all cars sold in the japanese domestic market are 180km/h limited (like bikes) but the same model sold in aus comes with the limiter removed (and usually different speedos which astronomical top speed readings to make people feel better).
 

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I dont see the point really? Gaining top speed over 185km/h on Australian roads?

I've only seen speed signs upto 110km/h so... ? Pretty sure if its for track use i can understand but still
 

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it can improve performance without changing a/f mixture
if the ignition times are changed, it can definitely improve performance if there is potential for it[hr]
its a chinese cdi...you can figure out the rest
I have used stock and after market Chinese cdi, stock not responding well but Chinese throttle response is excellent, now replaced stock with Chinese
 
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