Wirrr.....Wirrrrr.....Wirrrrr.......BANG

[Mrs Soup]

I washed my bike the weekend before last and now when I start it first thing in the morning, it goes BANG. :eek:

Normal starting technique - full choke, no throttle - turns over slowly then BANG. Starts on the button second attempt. Doesn't do it in the eveinings.

any ideas what i've broken??? :( :confused:

PS only washed with a cloth and brush, no hosepipe.

[Melnie Mouse]

After washing the bike always start it straight away, get's rid of water in exhaust pipes... run a few seconds before putting bike away... now if you start it, probably be fine, but remember to do that every time....

[A Yerbury]

I had the tank off recently and experinced similar although mine was struggling to pull the fuel initially hence build up then bang (cool yellow jet flames too) seems ok now. how many times has it done this or been doing this, if it is fuel or h2o it should hopefully sort itself as the fuel starts to flow or the components dry out? sorry if that was not a great deal of help. some wd on the electrics may help?
Alex.
ps very lovely boots btw but will the "and...." ever be revealed?

[stef]

has it really anything to do with the washing ?
i suspect back fire from carb icing, or some other reasons ?
It happens to mine, once in a while for those 'obscure' reasons.
I dont think there is anything you could do while washing it that would cause this. I'd put it down to cold weather.
(If it was, we would all be 'banging away' (so to speak) under heavy rain !)
( all the carbed ones anyway, before someone corrects me)

[Pedro]

Try changing the plugs - when mine are not in great condition, I get a back fire or even spitting back through the carbs

Ped

[Mrs Soup]

Thanks All - I think a change of plugs is probably in order.

[MotoNik]

I suspect you could have got some water in your airbox perhaps. Is the top of your airbox open? It's possible you may have got the air filter wet, and this is making the bike run a bit rich. This is causing it to over-fuel and then the unburnt fuel goes BANG in the exhaust!

A possible theory...

Nik

[caro'n'rich]

At our monnie owners meeting last week ("Gloucestershire" or Bristol as I like to think of it), we established that 3 or 4 of us regularly get back firing in cold weather, and common consent was that it was carb icing. One of our number is talking about designing some tubing affair that blows warmer air back into the carbs - but he doesn't mind riding something that looks as if it comes out of a 1970s episode of Dr Who!

Also I've had the devils own job getting my beautiful bike started, with the choke appearing to stick at closed, so the 'Rich' half of the team took the wd40 to the choke at the carb end and now it fires first time again, and so far no back firing either - but I know that's only because it hasn't yet been cold enough.

Oh, and the worst place to backfire eVER?--- ask Duncan!
Caro