NC35 starting issuses

[shaneblob]

Hey gents my names Shane from Aus.
Bought a parts bike and have slowly built her up over the last few years.
Shes finally ready!!

When I first got her I got a new battery and she used to start fine, straight away no issues (albeit some bogging down issues 7000rpm+ from memory). I let it sit for probably 10 months without trying to start.

Now when I try and start (with battery fully charged) coughs and splutters sometimes, backfires VERY loudly, but doesn't get going!
Although one day after about 2 batteries worth of trying to start, left it for an hour, came back and surprisingly started first go?! I thought shit yeah. Let her sit for a few minutes, give her a few little revs, cool! Turned off. Put fairings back on. And wont start again (within an hour of starting it..?).

My guess is electrical fault?

Any help would be greatly appreciated. Very anxious to get her registered.

[Morespeedvicar]

Hi an welcome to the forum. I would think its the spark plugs that are wet with petrol. The carbs may need a clean too, with it been sat and bogging a bit, but i'd try an take the plugs out an dry them out with a blow torch or on a gas cooker (when theres know body female watching....), get the electrode tips glowing if you can. Give them a wire brush too when you dried them out. You can check there sparking when you've cleaned them up. You may get away with just doing the back ones, if your lucky.
Hope it helps
Ian

[shaneblob]

Thanks for the reply!

I've taken the plugs rear plugs out, dried and brushed them.
I only get a very faint spark though. And I tried just putting a screw driver into the spark plug cap and leaving a 3-4mm gap to ground and still only a very faint spark.

Hmmmm

[racingt]

You probably know this, but are you starting the bike with the the throttle closed? Open throttle will flood the carbs.
Here in the UK, it's choke on, throttle closed most of the year.
Maybe this will help.

[Patch29]

Hi Shane, have you adjusted the mixture or idle screws???

[shaneblob]

Yeah I've been trying to start it with zero throttle.

And no Patch I haven't changed any carb settings.

Thinking of just taking her to the mechanics to see what he can do. Is that wise or is there something else I can try?

Cheers lads

[magg]

Check fuel flow from tank by sucking on vacuum valve hose.

[shaneblob]

At the moment I'e got the tank completely off and just feeding the fuel hose with a funnel.
I've also blocked off the vacuum hose going into the carbs.

So as far as I can tell its getting fuel (the plugs get super wet)

[magg]

In that case suggest you could remove all plugs, drain carbies, disconnect your fuel source and crank engine with RUN/STOP set to STOP ie no ignition, to clear fuel from cylinders. Refit plus and crank again. May need to repeat process a few times before plugs come out dry. With clean dry plugs and no fuel in cylinders, reconnect fuel source and try starting again.

If plugs come out wet again then sticking needles could be your problem. Standing for so long unused could mean a carby clean. DIY unless money is no object, cost at repairer will be high simply because working on an NC30/35 is labour intensive.

[Neosophist]

as above really.

this bike will never start with wet plugs.


get them out as magg has said and crank the cylinders to push out any fuel and let dry out for an hour or so.. while you do that make sure you are clean plugs.. put the tips on gas stove for some minutes to clean up and wire brush.

perhaps you might need new plugs after that.

if its wetting the plugs though it is a good chance oyu need to rebuild and clean carbs, its not hard and there is much info on the guide thread but be prepared to buy some new sealing O-rings (litekblair probably sells a viton ethanol reistant rebuild kit) and replace the inlet rubbers to save you airleak trouble and refitting trouble)