nc30 starting procedure

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pugparcels
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nc30 starting procedure

Post by pugparcels »

ok, i have today for the first in 9 months fired up my little '30. i know the procedure to start ( full choke - no throttle ) my question is what roughly should she idle when on full choke? 2k, 3k, 4k or more?

i removed the idle adjustor a while ago of the carbs, i am not 100% sure of the position it was sat in, the carbs have been completely stripped and rebuilt. she idles at around 3 & 1/2k, which can change depending on whether i screw the idle adjustor in or out a bit - is this about right?

i am now running my laser race can which wasn't on ther last time i started her so i am getting a lot of back fire and the occasional flame! this is down i think to the very tired old carb rubbers, so i will be replacing these. they are standard jets in the carbs which will require changing to run better with the race can, but i want to get the basics done first then tinker later.

Image

so after this rambling....

roughly what should she tick over at with full choke on start up & lots of popping flames down to poorly carb rubbers?
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force-v4
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Re: nc30 starting procedure

Post by force-v4 »

Thats exactly how i start my bike.

@ first, when cold, it runs @ around 2 & a bit thousand rpm & then builds up to about 5000rpm which i run it @ untill it reaches temp.

last year, it started popping, banging & flaming on warm up & it was due to knackered plugs. as soon they were changed, the problem stopped.
pugparcels
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Re: nc30 starting procedure

Post by pugparcels »

i know the plugs are not perfect, i did the old 'in the oven' trick earlier and that made a difference - in the fact that she actually started but i know my carb rubbers are knackered so i got a good feeling too much air 2 fuel ratio causing the bad idle & poping.

will try carb rubbers first as there cheaper than plugs! at least i know the way she is ticking over is right with the change in revs etc and when you say up to temp, what temp / where on the temperature dial roughly? seems a really stupid question but i have not had a carb'd / manual choke bike since my rs125 7 years ago. all of the others have been fuel injection with out chokes so press the starter and walk away!
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Re: nc30 starting procedure

Post by Neosophist »

You should take the choke off after 30 seconds and warm it up by revving it gradually. You'll find it'll idle (albeit low and lumpy without choke after 30 seconds)

Keeping the choke on any longer is just using more fuel than is needed / fouling up the plugs / richening the engine up / affecting lubrication.

Straight from the horses mouth, well Mr Honda's (According to my VFR owners manual...)

Starting Procedure: (normal air 10 - 35c)

Pre-Check: Make sure transmission is in netural, engine stop switch is at RUN and fuel valve is ON. Insert in key and check for oil pressure warning light illumination and neutral light illumination.

1. Pull choke lever back all way out to fully open.
2. Operate the starter button leaving the throttle closed.

* Do NOT open the throttle when starting the engine with the choke open. This will lean out the mixture, resulting in hard starting.

Warning:

The red oil pressure light should extinguise after a few seconds of engine starting. If the the light starts illuminated stop the engine immeddiately and check engine oil level. Low oild pressures can cause seriously engine damages.

3. Immediately after the engine starts, operate the choke lever to keep fast idle at 1,500-2,500 rpm.
4. About a half a munite after the engine has started push the choke lever forward all the way to fully closed.
5. If idling is unstable, open the throttle slightly.

High Air (35c+)

1. Do not use the choke.
2. Open the throttle slightly.
3. Operate the starter.

Low Air Temperatue (<10c)

1. Follow the steps 1 - 2 under Normal air conditions.
2. Warm up the engine by opening and closing the throttle slighty.
3. Continue to warm up until the engine tuns smoothly and respons to the throttle when the choke lever is at fully closed position.

Cautions:

*Snapping the throttle or fast idling for more than about 5 mins at normal air temperature may casue exhaust pipe discolouration.

*Extended use of the choke may impair piston and cylinder wall lubricaton.
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pugparcels
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Re: nc30 starting procedure

Post by pugparcels »

cheers neo,

will have a look tonight and see how she starts with that method. I have a good feeling she is likely to die shortly after turning the choke off even whilst opening the throttle. but again this i believe will be down to the poor carb rubbers letting too much air through affecting the mixture. which then causes her to stall. with the choke open she idles fairly well, as the amount of fuel must be fairly evenly matched to air coming through.

have spoken to rick this morning and he can sort me out with some carb rubbers. does this sound reasonable diagnosis?
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force-v4
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Re: nc30 starting procedure

Post by force-v4 »

I have warmed my NC30 up like that for 3 years - every time it goes out - i have no problems with the plugs, rich running or bore washing.
& im really not bothered about its fuel consumption. if i was worried about that, i'd get a cg125!

i warm the bike up on FULL choke until it reaches 90, takes about 5 mins, then i turn it off & away i go - no problems & all warmed up - a few of my lot use the choke as Neo has explained & those bike run like a sack of crap for about 20 mins, jurky, snappy & horrible to ride.

i dont ride cold bikes, i use expensive oil & expensive fuel so im sure i'll be just fine - if anyone is going to have a problem it would be people running bikes on cheap mineral oil - cheap oil washes off from the bores far easier.

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