A problem not sure what it is

[Folcan]

I had a problem this morning not sure what is causing it but from my limited diagnostic abilities I thought it was to do with the fuel system.

It started on Sunday. I was riding home from a friends place and stopped at a give way and it cut out for no reason. as the clutch was pulled in fully it stopped dead from about 1000rpm which is around the idle I think for my bike. started up when I hit the starter

then this morning I was riding along to uni on quay st and my bike just cut out when I stopped at the traffic lights, it cut out as I pulled the clutch in and there was no signs of running out of petrol (the lack of power or the noises) it just cut out straight from going like 1k rpm.

It started up first time and I rode off then come up princes st I was accelerating and it all of a lost power and then regain it and I thought maybe running out of petrol. I put the fuel tank onto res, then at the traffic lights at the bottom on princes st it cut out and would not start. which resulted in me having to push it to the side of the road and fiddle. I opened the tank and it was more then half full. I put it back onto on. then it started first time.

during both of these times the electrics seemed to be working fine and there was no sign of loss of power or anything before the time on princes st.

I have had no problems starting it in the past in the mornings it started first time every time. so not sure whats going on. I thought it might be the fuel, but it could be anything

I have 2morrow off uni so anyone have any ideas on what I could check?

[surfer]

It sounds like it is either fuel or electrical.

Eliminate the possibility of electrical by checking how much charge your battery has. Get a multi-meter ($40 from DickSmith or borrow one) and read across the two battery terminals for the voltage without the engine going. Should be about 12.5 volts. This will indicate whether your battery is stuffed or needs a re-charge.

With the engine going it should read somewhere in the region of 13.5 volts. If this is so then your battery is being recharged. Otherwise you have a charging problem i.e. your battery is not being charged up properly.

Next have a look for any bad earth connections or corroded points on the earth connection on the battery earth lead at the battery and at the frame where it bolts on. Clean off corroded parts and tighten up and make the connections secure if they are loose.

If all this is ok, a question for you. When was the last time you changed the spark plugs? If you can't remember they probably need changing anyway. Cheap and easy to do.

After you have done this have a look in the float bowl under the carbeurettor for debris. You do this by unscrewing the bowl. Look at your manual (if you don't have one, get one). If you have crap in your carb bowl chances are it is fouling the jets, so you need to blow these clean. Do not poke anything into the little holes to clear stuff. Then put an inline fuel filter in the fuel hose betwen the tank and the carb (you can get one of these from repco - make sure you put it on the right way).

That should keep you busy. Let us know how you get on and whther it is fixed.

[Disco Dan]

Do you have a switch on your clutch lever?

[Folcan]

thanks for that ill see what I can do.

Yes it does have a clutch switch, ill check that too

edit: Checked the battery it is fine. I didnt get to check for any corrosion as its dark and I couldnt see too well. I have a look 2morrow.

argh the carbs thats gonna be a mission with it being V4 and all :(

[Folcan]

ok I checked for corrsion. I found some on the postive battery terminal, I havent gotten to clean it properly but I tried scraping it off and stuff... gonna goto the shop and get some bi carb and a file to fix it properly and ill see if that fixes my problem

I had a look around at other cables and I dont really see anything that looks suspect.

[more_fasterer]

Could be a bad batch of fuel? Water contamination? Try putting a capful of meths in the tank

[surfer]

Could be a bad batch of fuel? Water contamination? Try putting a capful of meths in the tank

If you drain the float bowl on the under side of the carb first into a small container you will spot whether your fuel is contaminated by water. If it is contaminated there will be small water globlets floating in there.

[Folcan]

I dont know about the fuel.. I was going to the shop to get some stuff to try fix the corrosion and I went over some bumps and it started dieing. So bad connection somewhere? or could it be something with the carbs... its really intermitant cus I road home and didnt have any problems even thou I went over a few bumps

Ill try check it thou. I only found a nc30 manual no nc24 manual

[surfer]

I dont know about the fuel.. I was going to the shop to get some stuff to try fix the corrosion and I went over some bumps and it started dieing. So bad connection somewhere? or could it be something with the carbs... its really intermitant cus I road home and didnt have any problems even thou I went over a few bumps

Ill try check it thou. I only found a nc30 manual no nc24 manual

Make a list from the suggestions you have recieved and work through it one at a time. After each one has been done, go for a short local test ride. That way by a process of elimination you will be able to find out what it was and if it happens agian sometime in the future it may be the best place to start.

[skidMark]

FOr it to suddenly cut it's clutch switch...

crc/ bypass wire it.

[NinjaNanna]

FOr it to suddenly cut it's clutch switch...

crc/ bypass wire it.

Almost true, the clutch switch maybe the symptom not the entire cause, the clutch switch will only cause the motor to cut out if the bike is in gear AND the stand is down.

If it can be traced to the clutch switch (which I'm not saying it is) then the real problem is more likely both the clutch switch and the Side Stand Switch, what may have happened is that its contacts are dirty and the switch thinks the stand is down - but its not. As a result the electrics are doing exactly what they should and cutting the engine. As a precaution I'd clean and crc both the clutch and side stand switches and while you are at it do the front brake light switch as well, they've caught me on 2 different bikes.

Good luck

[skidMark]

Almost true, the clutch switch maybe the symptom not the entire cause, the clutch switch will only cause the motor to cut out if the bike is in gear AND the stand is down.

If it can be traced to the clutch switch (which I'm not saying it is) then the real problem is more likely both the clutch switch and the Side Stand Switch, what may have happened is that its contacts are dirty and the switch thinks the stand is down - but its not. As a result the electrics are doing exactly what they should and cutting the engine. As a precaution I'd clean and crc both the clutch and side stand switches and while you are at it do the front brake light switch as well, they've caught me on 2 different bikes.

Good luck


That be what i was thinking captain. hmmm itws a tricky one, intermittent problems are a pain.

[Folcan]

I had a look to see the sidestand switch, and its not there... It doesnt look like this bike has one at all.

[NinjaNanna]

I had a look to see the sidestand switch, and its not there... It doesnt look like this bike has one at all.

Sounds to me like someone removed it already (I'm thinking because they had the same problem you have now).

I'm sure there will be a loose connector hanging nearby the stand, depending on how your electrics are wired it will either be just hanging loose with nothing pluged in, or have a piece of wire or something jambed in there to short out the connection.

Which ever it is give the connector a really good clean!!!!

If they've jammed a piece of wire in there to short the connection, then make sure you pull it out and clean it up before putting it back together. Once its back together tape it up to stop more grease and road crap getting in there.

[Folcan]

would a neutral switch have the same effect? as it doesnt look like theres even mountings for a side stand switch, and I didnt find any loose connectors.

but the nc30 manual shows a neutral switch what ever that is im guessing by the gearbox to detect if your trying to start it in gear with the clutch out

[skidMark]

Upon further thinking while falling asleep i suspect its the handlebar kill switch has dirty contacts, because the hondas from memory connect the wires to make it run...dodgy conenction = buggered....

my mates hornet used to do the same thing...we rebuilt the switch block pulled it all to bits sanded all contacts etc...never a problem since.

[skidMark]

would a neutral switch have the same effect? as it doesnt look like theres even mountings for a side stand switch, and I didnt find any loose connectors.

but the nc30 manual shows a neutral switch what ever that is im guessing by the gearbox to detect if your trying to start it in gear with the clutch out


Yeah i wire will go onto a spade /male connecter lug down by the sprocket, sometimes under sprocket cover, sorry i cant remember.

[NinjaNanna]

would a neutral switch have the same effect? as it doesnt look like theres even mountings for a side stand switch, and I didnt find any loose connectors.

but the nc30 manual shows a neutral switch what ever that is im guessing by the gearbox to detect if your trying to start it in gear with the clutch out


OK without having the right Electrical Diagram unfortunately all I can do is offer generic advice.

My recommendation is to join some VFR specific forums, I'm certain you'd get the manual that you need from there. Once you have it post the Electrical Diagram and I may then be able to help a little better.

[vifferman]

My recommendation is to join some VFR specific forums, I'm certain you'd get the manual that you need from there.
You may also get an answer to your problems.
The UK one (http://www.bikersoracle.com/vfr/forum/index.php?) is pretty good, as they have a 400 section.

Re-reading your first post, there is a chance it could be a dodgy connection in your clutch lockout switch, as you said it cut out when you pulled the clutch in. However, given that both times it started again immediately, that's not necessarily the culprit. There are some fueling issues that can cause this - one is when the idle's set a little low (especially if the bike isn't running well or is out of tune). Another is if the fuel tank isn't vented properly, which can result in poor fuel flow. I dunno what venting your bike has - it's either via the fuel cap, or a vent hose. If the vent in the cap is blocked, or the hose is pinched, this can result in the bike cutting out erratically. On some bikes (the Firestorm, f'rinstance), even a bit of road spooge in the end of the vent hose can cause problems like you've described.

[Folcan]

hey thanks for all the replies will keep me busy for abit

But I rode it out to uni and back without problems so it may have been the corrosion I fixed up properly with bicarb etc.

But ill see if it still gives hassles ill try posting on that other forum

argh the joys of having a bike that is one year younger then me :P

[surfer]

Make a list from what everyoine has posted and work through it one at a time.

Also in your manual you might have a fault finding section, read that as well.