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Ender EnZed
7th November 2009, 11:00
Sometimes when I prod the starter on my VFR from cold it makes a (fairly) loud gunshot/backfire type noise coming from the middle of the engine. It did this yesterday and afterwards prodding the starter resulted in nothing but a clicking like the battery was too drained to do anything. After a few more clicks with nothing at all happening it started just fine perfectly normally. Anyone know what's going on here?

mossy1200
7th November 2009, 11:28
Sometimes when I prod the starter on my VFR from cold it makes a (fairly) loud gunshot/backfire type noise coming from the middle of the engine. It did this yesterday and afterwards prodding the starter resulted in nothing but a clicking like the battery was too drained to do anything. After a few more clicks with nothing at all happening it started just fine perfectly normally. Anyone know what's going on here?

Sounds like a carbs filled a cylinder with fuel.Wont turn over its filled it up completely as there would to much compression.Check the float needles perhaps for a bit of grit or stuck float.It may have blown a fuse after a couple of shots with the starter motor being unable to turn it over.

Ender EnZed
7th November 2009, 12:11
It may have blown a fuse after a couple of shots with the starter motor being unable to turn it over.

It started fine less than a minute later so that should mean everything's still there right?

YellowDog
7th November 2009, 12:26
Sometimes when I prod the starter on my VFR from cold it makes a (fairly) loud gunshot/backfire type noise coming from the middle of the engine. It did this yesterday and afterwards prodding the starter resulted in nothing but a clicking like the battery was too drained to do anything. After a few more clicks with nothing at all happening it started just fine perfectly normally. Anyone know what's going on here?
Starter motors start doing that when they are on their way out.

Have no idea about the bang though.

Do you have an exgirlfriend who thinks you're a Shagnasty ?

Perhaps she's trying to shoot you dead !

Dangerous creatures.

Ender EnZed
7th November 2009, 12:52
Starter motors start doing that when they are on their way out.

:buggerd:, if that is the case. I'm still thinking it's related to the bang.



Do you have an exgirlfriend who thinks you're a Shagnasty ?

Perhaps she's trying to shoot you dead !

Dangerous creatures.

Not that I know of, though that would be a prefered explanantion over "my bike's about to melt".

hayd3n
7th November 2009, 13:00
if its a crunch noise its a starter engaging issue, ive had that once but never had it again

Ender EnZed
7th November 2009, 13:03
if its a crunch noise its a starter engaging issue,

It certainly has a crunchy nature to it.


ive had that once but never had it again

This is about the solution I was after. :2thumbsup

Ender EnZed
7th November 2009, 13:14
Started fine first prod just now. Time for a ride methinks.:woohoo:

racerhead
7th November 2009, 15:42
The bang could be caused by a loose electrical connection onto the starter motor. The bang your hearing could actually be a large spark jumping from the cable to the starter or cranckcase.

gwigs
7th November 2009, 16:59
Could be a carb problem,probably backfiring due to float height..
just my 2 cents worth ..

Chrislost
7th November 2009, 17:01
Sometimes when I prod the starter on my VFR from cold it makes a (fairly) loud gunshot/backfire type noise coming from the middle of the engine. It did this yesterday and afterwards prodding the starter resulted in nothing but a clicking like the battery was too drained to do anything. After a few more clicks with nothing at all happening it started just fine perfectly normally. Anyone know what's going on here?

My race beast was doing that, along with rattling like a dead thing.
Raced it for a year then it stopped turning over on teh starter. Upon pulling the side cover off i found 2 of the 3 starter clutch bolds half out, and after fishing in the sump with a magnet found the 3rd...
might pay to be a bit more proactive then me and pull the right-hand cover off, and check the 3 bolts.
one of the gears is held in place by the case, dont worry, its pretty easy to put back together and nothing will fly out. just be sure to buy a new gasket from honda before you do it or you might be dripping oil to work for the next few days...
Otherwise as somone has said, carbies are flooding a cylinder, try turning the gas tap off when ya park it and see if it keeps doing it, r6_kids bike was doing that, pm him and see what it was?

LBD
7th November 2009, 17:09
I had someone play a prank on me at the surfclub once, they swapped the left and right spark plug leads over on my CB350....lots of licking and backfiring later...I gave up...Got a mate woth a car to tow me up to 45mph in 3rd.

Let go the rope, dropped the clutch and KaaaBoooommm

....Blew a carb out of the rubber mounts and left it swinging on the throttle cable and fuel line.....

Found it that night after I trailered the bike home, lifted the tank off and thought...hmmmm that dont look right.

Bastard!!!!!

hayd3n
7th November 2009, 17:27
I had someone play a prank on me at the surfclub once, they swapped the left and right spark plug leads over on my CB350....lots of licking and backfiring later...I gave up...Got a mate woth a car to tow me up to 45mph in 3rd.

Let go the rope, dropped the clutch and KaaaBoooommm

....Blew a carb out of the rubber mounts and left it swinging on the throttle cable and fuel line.....

Found it that night after I trailered the bike home, lifted the tank off and thought...hmmmm that dont look right.

Bastard!!!!!
i take it you arnt m8s anymore?

LBD
7th November 2009, 17:33
i take it you arnt m8s anymore?


Mate gave me a tow...Dad picked me up with the trailer...never did find who swapped the leads....Bastard!

Ender EnZed
7th November 2009, 18:16
Otherwise as somone has said, carbies are flooding a cylinder, try turning the gas tap off when ya park it and see if it keeps doing it

I always turn it off when I park it..............................[(<brain realigns with reality>)].............or a day or two after parking it. I'd forgotten about that.

Ender EnZed
7th November 2009, 18:26
The bang could be caused by a loose electrical connection onto the starter motor. The bang your hearing could actually be a large spark jumping from the cable to the starter or cranckcase.

Sounds more like it involves metal than electricity to me but then I'm not really too sure what either of those sound like. If that was what was happening would that be a fairly serious problem? Would it do it every time?

Chrislost
8th November 2009, 15:39
Sounds more like it involves metal than electricity to me but then I'm not really too sure what either of those sound like. If that was what was happening would that be a fairly serious problem? Would it do it every time?

easy to check tho, pop the bottom fairing off, look in behind the bottom radiator at the round cylinder thingy(starter motor)...

There should be a bit of rubber covering the end of the wire going to it, BOTH nuts should be tight.

Ender EnZed
9th November 2009, 13:17
easy to check tho, pop the bottom fairing off, look in behind the bottom radiator at the round cylinder thingy(starter motor)...

There should be a bit of rubber covering the end of the wire going to it, BOTH nuts should be tight.

I had a look and nothing seemed out of place. I'm thinking its probably just a carbie issue that hopeful will keep quiet provided I remember to turn the fuel off as soon as I park it up.

Chrislost
9th November 2009, 17:13
I had a look and nothing seemed out of place. I'm thinking its probably just a carbie issue that hopeful will keep quiet provided I remember to turn the fuel off as soon as I park it up.

Does the bike rattle at idle? if not then probably carbie, if it does then tis probably the starter clutch.
I would get it fixed asap, if you bend a crank(fuel dosnt compress like air does) it wont be cheep!

The Pastor
9th November 2009, 17:19
to check if the cylinders are flooded you pull the plugs out, make sure the kill switch is OFF and hit the starter button - fuel will piss out the spark plug holes if it is the case.

kwaka_crasher
10th November 2009, 13:40
to check if the cylinders are flooded you pull the plugs out, make sure the kill switch is OFF and hit the starter button - fuel will piss out the spark plug holes if it is the case.

Except that most bikes won't wind off the starter button with the kill switch off - they're interlocked.

The Pastor
10th November 2009, 13:47
Except that most bikes won't wind off the starter button with the killswitch off - they're interlocked.
Thats news to me......

Works fine on my bike.