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Re: Carb problem maybe? Misfire and spluttering between 7-9k
Posted: Fri Jul 25, 2008 9:41 am
by revved-up
Yes there is an EVO Can, and its bloody LOUD!! lol
I was told the engine had a 'sharp' cam in it, and that the previous owner used to Take it to brands hatch, which is where he had an OFF, and it sat in his garden ever since.
I doubt he would have just 'whacked' the can on without sorting out the jetting, especially if using it on track, you'd want it tip top.
Could the battery be at fault, or does this sound definately carb related?
Thanks for your help so far Sanchezz. Anyone else got any ideas, or had similar problems?
Thanks, Tony.
Re: Carb problem maybe? Misfire and spluttering between 7-9k
Posted: Fri Jul 25, 2008 10:36 am
by Sanchezz
I was told the engine had a 'sharp' cam in it
Think you have found your problem. :) i would get it on a dyno, sounds like they have either just fired the cam in without changing the fueling or just done a really crap job of smoothing the power curve out.
Re: Carb problem maybe? Misfire and spluttering between 7-9k
Posted: Fri Jul 25, 2008 12:00 pm
by revved-up
Thing is though, I doubt it has... It revs just like a normal NC29, although it seems to pickup a little quicker... Surely a sharp cam should stick more power at the top end, No?
We own a scooter shop, and ive had the mechanic go out on it, and he reckons that its definately the carb thats the problem...
Im going to get a new battery today, see what happens, although I doubt it'll do anything, but it needs replacing anyway.
Re: Carb problem maybe? Misfire and spluttering between 7-9k
Posted: Fri Jul 25, 2008 8:13 pm
by revved-up
Righteo...
Ive changed the battery for a new'un and it's quite a bit better, but it doesn't seem to misfire now, its just really hesitant. If you clutch it past the hesitating it flies to the redline.
The rev counter now goes a bit mad between 5k and 9k which is where it hesitates. And the rev counter is also very bouncy all the time, and isn't smooth at all.
I was at 11k revs slowing down, and as soon as the revs dropped down to 9k the rev counter went mad until the revs dropped below the 5-6k mark, although it varies at when the rev counter goes mad...
The lights also flicker when the bike is revved...
Is this a problem with the charging system???
thanks.
Re: Carb or electrical problem? Hesitant between 7-9k
Posted: Sat Jul 26, 2008 12:25 am
by gtlover
Something ain't right...
FWIW I blew the fuse for the instrument & turn/rear signals - and lost not only my lights but half of the spark as well! I rode for 2 days trying to figure out why it sounded odd, ran rough in the midrange, and revved up so slowly. Apparently, when you only get spark on 2 cylinders it sounds (and feels) like you're riding an old Ninja250. Oh, and I was riding for 2 days with NO brake lights or turn signals!
Go through all the electrics, little things can make a big difference.
Re: Carb or electrical problem? Hesitant between 7-9k
Posted: Sat Jul 26, 2008 9:14 am
by leopard_pagan
"I doubt he would have just 'whacked' the can on without sorting out the jetting"
>Youd be surprised just how many dont even know that you need to re-jet after a can change!
"The lights also flicker when the bike is revved"
>check the voltage outputs with bike switched off, idle, and revved up. i dont know what the readings should be but sounds like the regulator/rectifier may have issues...
"blew the fuse for the instrument & turn/rear signals - and lost not only my lights but half of the spark as well!"
>there is a way round avoiding that happening again. same thing to me last winter but i knew what it was...
when the fuse blows it deprives the speed limiter power (it sits inside the speedo), signal is lost to the CDI unit and puts the bike in to restriction mode.
way round it is to fit the resistor mod in at the CDI end of the bike. that way when the fuse blows again.... you dont ride 1/2 a bike!
Re: Carb or electrical problem? Hesitant between 7-9k
Posted: Sat Jul 26, 2008 12:12 pm
by revved-up
Thanks Leopard Pagan!
Do you check the voltages off the battery??
Thanks, Tony.
Re: Carb or electrical problem? Hesitant between 7-9k
Posted: Sat Jul 26, 2008 2:52 pm
by revved-up
Right...
12.6v with engine off, 13.5-14v at tickover... Revving it makes no big difference to the voltage though, it stays between 13.5 and 14volts.
Does that sound Ok?
Re: Carb or electrical problem? Hesitant between 7-9k
Posted: Sat Jul 26, 2008 2:53 pm
by revved-up
Where does the rev counter take its reading from??
Re: Carb or electrical problem? Hesitant between 7-9k
Posted: Sat Jul 26, 2008 10:23 pm
by leopard_pagan
CDI unit i think
*checks manual for wiring diagram*
*update*
2 wires in/out of Tacho/rev counter:
1 common ground (green) and
1 yellow/green wire direct to/from the CDI unit