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No Air Filter + Bike not starting questions

Posted: Sat Jan 31, 2009 8:28 pm
by ybanrab
Hi All,
I managed to get some more time on my basket-case NC30 today. Mainly this was re-fitting the rear hub/brakes/wheel and re-fitting the lower Rad.

The bike ran when I brought it a year ago, but I've not run it in over 6 months and it now won't start. I checked the plugs today and there's sparks, although they don't look that strong. I'll put the battery on charge and take a look at the sparks on my other bike tomorrow so I know what a good spark looks like. I unscrewed the drain ports on each carb to check that there's fuel in each float chamber and there is.
I guess my question is: what should I check next?

The other thing that surprised me way that when I got the airbox off was that there was no air filter in there! I had a quick search on the forum and couldn't find any mention of running without a filter, so I'm guessing it's not done the engine any favors. Would the lack of filter make it harder to start?

Given that I have no idea of the history of bike, I have a suspicion that the answer may to get the carbs off, check the floats aren't stuck, check the jetting, balance them then replace the air filter, but I'm hoping there's something else I can check before having to extract the carbs. I spent 5 hours outside working on the bike today and I still don't think I've warmed up!

Thanks in advance for any advice

Barny

Re: No Air Filter + Bike not starting questions

Posted: Sun Feb 01, 2009 9:06 am
by V.
I'd get a filter bunged back in before taking it on the road, don't want any nasty shite getting into the carbs. Not having an air filter in may make the bike run lean but apart from that it shouldn't stop it from starting. Before you go taking the carbs apart I would try draining the fuel from the tank and putting in fresh fuel. Could be that its gone off, better to start with the basics first.

Re: No Air Filter + Bike not starting questions

Posted: Sun Feb 01, 2009 8:36 pm
by Cammo
ybanrab wrote:Would the lack of filter make it harder to start?
Yes.
Given that I have no idea of the history of bike, I have a suspicion that the answer may to get the carbs off, check the floats aren't stuck, check the jetting, balance them then replace the air filter, but I'm hoping there's something else I can check before having to extract the carbs.
Sounds like a good plan.

Re: No Air Filter + Bike not starting questions

Posted: Tue Feb 03, 2009 1:02 am
by mrfletch
Have you tried to get the bike running by using a squirt of easy start? At least this way you know the igniton system and compression are good and can be eliminated before tearing the carbs apart. How ever id say running a bike with out the filter may cause the bike to run slightly lean but not to the point of the engine not starting.

Re: No Air Filter + Bike not starting questions

Posted: Tue Feb 03, 2009 11:00 am
by wullvfr
it should not effect the bike starting,many times i had started the nc30 with the tank,air filter housing off and it would start no problem at all.

i think running the bike without the filter would only effect the running of the bike once you get up to speed,causing the bike to run lean.

does the choke work?



william

Re: No Air Filter + Bike not starting questions

Posted: Wed Feb 04, 2009 5:53 pm
by ybanrab
Thanks for all the advice guys. I'll order an air filter tonight and try swapping out the fuel and getting some easy-start on the case.

I did try the choke and that didn't help.

Last time I started the bike it would only start with choke. Is that normal?

The other question I have is how do you go about disposing of old fuel? I asked a car mechanic friend and he said they have real trouble disposing of the stuff. My guess was going to be at dumping it into the tank of my campervan, whilst filling the rest of the tank with fresh fuel. The thought being that when it's diluted and run through an engine that seems unfussy, it would be ok. Does that sound like a plan? Any alternatives?

Thanks again

Barny

Re: No Air Filter + Bike not starting questions

Posted: Wed Feb 04, 2009 8:12 pm
by wullvfr
ybanrab wrote:Last time I started the bike it would only start with choke. Is that normal?
that is perfectly normal if the engine is too cold to start without choke.if you could only start the bike from warm with the choke then that is not normal.
ybanrab wrote:Does that sound like a plan?
don't see anything wrong with that!!!!!


william

Re: No Air Filter + Bike not starting questions

Posted: Wed Feb 04, 2009 10:05 pm
by Cammo
Clean the carbs and whack an air filter in, they don't like to start without one.