Ypvs only run for 5 seconds ????

[miker1bike]

Been in the garage all day today fitting some kr1s carbs got them on eventually and got bike started but slides would not close properly so engine was ticking over at about 2500 revs anyway fixed that by modifying cable lengths and all seemed well reving cleanly and sounding sweet. Had bike running for about 10 mins then all of a sudden it just stopped as if it ran out of fuel. Put it on reserve and tried again it fired for 5 seconds the just died !
Engine was quite hot so left it for a while to cool tried again 30 mins later and same problem starts up after many kicks then runs for 5 secs or so the stops ?
Removed carbs checked inside float bowls of both & cleaned them out with brake cleaner put back on and same problem runs then dies
Changed the plugs for brand new still no difference
Now getting really cheesed off so decided to put original carbs back on which I've had no problems with & guess what run for a few seconds then nothing it then takes about 20 kicks to make it fire again but it just won't run

Have checked all connections to coil,cdi,ect but can't find anything

Any ideas ?

1wt engine in lc frame running oil pump not premix

[muddyfox]

well if you deciede to sell carbs pm me

as for your bike, maybe its flooded, have you checked the plugs to see if they are wet? if they are wet id say float levels,

have you put the oem carbs the right way round, im not sure it will run with out balance pipe, im sure some one will correct me,
are you running air box, maybe some dirt has got in to those little jets (back) on the mouths of the carbs,

maybe tank has a air lock, thats why mine was acting weird like a air leak on high revs, no fuel

hope this helps:)

[JonW]

sounds like fuel, filter ok?

[markhoopy]

Try running it with the filler cap off the tank to make sure the breather isn't blocked.

[midlifecrisisrd]

Try a remote tank to make sure it is getting fuel

Steve

[miker1bike]

I'm thinking it's probably flooded the plugs are really wet. Think the crankcase may be full of fuel will remove the plugs & kick it over as much as possible to pump fuel out!
Is there any other way to check if this is the case ?

[billyboy]

don't know my way around these carbs ,but have the float settings been disturbed with changing mains etc leading to the flooding ?

I'd also be sure you have most of the fuel out of the cases before trying again

[muddyfox]

Dec 1, 2014 22:22:24 GMT 1 billyboy said:

I'd also be sure you have most of the fuel out of the cases before trying again

whats the solution for this? i cant find any info, see some one use a lighter before lol

[frosti]

Pressurized air?

Carbs of, exhaust of, then piston at bottom, blow through reed, fuel should exit via exhaustport, and the same on the other cylinder.

Then new plugs,,;-) 

[bigkenx]

I know this sounds daft but I remember having a similar problem and what it was that it wasn't getting a proper flow of fuel inside the tank shit was blocking the pick up and stopping the flow then you get on disturb it by kicking it up and it would flow fuel again then you get off leave it on side stand and the shit would draw to the pick up again when I cleaned the tank there was shit and ball bearings in just something to check

[greasemeup]

I had a similar issue to kenx, it was a blocked breather for mine. Not so daft..