two quick questions nc29

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dunkenb
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Posts: 560
Joined: Wed Jun 03, 2009 9:39 pm
Bike owned: Cbr400rr nc29 type8 NSR250
Location: West Midlands
Re: two quick questions nc29

Post by dunkenb »

Yeah i was was quite impressed with the coke too. You tried the carbs yet?
dynamek
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Joined: Fri Jul 06, 2012 10:10 am
Bike owned: CBR400 NC29
Re: two quick questions nc29

Post by dynamek »

not yet unfortunatly, will be over the next two days though, once i find time to put her back together, also a bit afriad of spoiling the plugs again
dynamek
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Posts: 19
Joined: Fri Jul 06, 2012 10:10 am
Bike owned: CBR400 NC29
Re: two quick questions nc29

Post by dynamek »

i have a question though...from what i gather, the air inlets create the vacuum which draws through the petrol right? so is it that the petrol is being drawn through the wrong jet which is leading to the richness?? wouldnt there be a little petrol being drawn through due to the lack of vacuum? or have i just completly misunderstood carbs :(
dynamek
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Posts: 19
Joined: Fri Jul 06, 2012 10:10 am
Bike owned: CBR400 NC29
Re: two quick questions nc29

Post by dynamek »

started her up, she was reving quite nicely, wont idle at all but was burning on all cylinders, ran it for maybe 10 mine then left it for about an hour and tried again and only hot on 2 cylinders, i suspect its still spoiling plugs but thinking of taking it for a burn on saturday to see if i can blast through some goodness...also i noticed that there was quite alot of smoke coming out the carbs, i didnt have the filter on so i could watch it, and when the acceleration plates are open i can see a decent amount of white smoke just sitting right under the carbs, normal?
dunkenb
Regular Member
Posts: 560
Joined: Wed Jun 03, 2009 9:39 pm
Bike owned: Cbr400rr nc29 type8 NSR250
Location: West Midlands
Re: two quick questions nc29

Post by dunkenb »

Are you using new plugs? I clean mine in one of those little ultrasonic cleaners, come up like new.
Smoke out the carbs doesn't sound good but it sounds like your going in the right direction. Have you balanced the carbs?
dynamek
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Posts: 19
Joined: Fri Jul 06, 2012 10:10 am
Bike owned: CBR400 NC29
Re: two quick questions nc29

Post by dynamek »

hey mate
yup new plugs, unfortunatly dont have ultrasonic cleaner so cant get them in one of those, just fired it up again and ran four cylinders in the higher rev range, so im guessing this is a jets/air inlet problem? it runs nice at around 10000, still a bit smokey but yeah, will pull the plugs tonight and see how they look, cant really afford a balance :( its around $400 i think here, if that was the only problem then i would do it but im afraid ill get it done at she will still run rich
dynamek
Settled in member
Posts: 19
Joined: Fri Jul 06, 2012 10:10 am
Bike owned: CBR400 NC29
Re: two quick questions nc29

Post by dynamek »

pulled the plugs and all of them completly black and smelling of fuel, interestingly i was able to run the black away with a cloth to resonable affect, but shes obviously still running way rich...any other ideas?
dynamek
Settled in member
Posts: 19
Joined: Fri Jul 06, 2012 10:10 am
Bike owned: CBR400 NC29
Re: two quick questions nc29

Post by dynamek »

interesting thing to note is that i could rub off the soot pretty easy from the plugs just using a cloth, does that mean that the bike just needs to be run and cleared through as it hasnt run for years, or is it actual rich running? ive heard that after sitting bikes can do that to plugs and the best thing to do is just to put cleaning foam stuff in the tank and keep running it through?
dunkenb
Regular Member
Posts: 560
Joined: Wed Jun 03, 2009 9:39 pm
Bike owned: Cbr400rr nc29 type8 NSR250
Location: West Midlands
Re: two quick questions nc29

Post by dunkenb »

I ran that redex stuff throught with the fuel first couple of times i filled up.
Also try adjusting the mixture a 1/4 turn in to lean it off a bit?
If theres no noticable difference i'd say there's still a bit of crap in the carbs?
Oh also you could take the mixture screws out and blow air through them from that end, they could be blocked at that end , the holes by the butterfies where they exit are really small and easily blocked. :o
dynamek
Settled in member
Posts: 19
Joined: Fri Jul 06, 2012 10:10 am
Bike owned: CBR400 NC29
Re: two quick questions nc29

Post by dynamek »

the mixture screws are already 3/4 more lean than stock, should i try anyways? ill get them out today and give them a clean out from that side to see if it helps

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