Dear all- I am running a fazer 1000 engine (basically an r1) the engine starts fine but as soon as I touch the throttle the engine stalls. I have tried the original air filter and box but no luck. The exhaust manifold still doesn't have it's gaskets (could this be the problem?) other than that I am stumped. Any ideas?!

Try the choke? try letting it warm up a little before giving it some throttle.

Could be a blocked main jet, what is your fuel pressure?

Yes I'm using the choke- fuel pressure seems fine, but I don't really know how to test this. Fuel pump certainly working as it idles fine ( with choke in)

I hate bike carbs, so although no expert do feel your pain. As this thread seems quiet then let me think aloud for you.
If nothing else it will promote it to the top of the list!

Bike engines will run on 3 or at a push 2 cylinders, so if it stalls then the problem is systematic (across all 4 carbs).
This (to me) suggests it isn't just some blocked progression holes or something that might happen to an individual carb.
If it idles smoothly then it indicate the carbs are balanced.

If you have no exhaust at all then I can imagine that might confuse things.

What fuel pump are you using? Frequently people try pumps from non-bike applications and they normally go back to the standard bike pump.

Do you think its getting too much fuel or too little?

Matt

sounds like it needs more fuel - after start enrichment. When you put your foot down your letting air thereby leaning out the fuel.

I've got the manifold and silencer on- and if you look at my photo's you'll notice I have some cones for air filters. All exhaust exits are getting hot so all cylinders are firing. It runs perfectly well at idle, with the choke fully on. As soon as I touch the throttle or lessen the choke it stalls. Any more thoughts?

And I'm using the bike fuel pump

Try running without the air filters on. Also take the fuel line out of the carbs and turn the engine over you should get a nice stream of fuel providing the pump is working correctly.

Hth Dan

Since it dies when you either touch the throttle or lessen the choke, both introducing more air into the system, then you aren't getting enough fuel to the engine.

You have higher flow open air filters? have the carbs been sat for a few months? are they used and you know no history?

I would bet either larger jets need to be installed, or blocked jets.

It idles exactly the same without the air filters on. Fuel pump is working fine. When I say touch the throttle and it stalls, I mean touch it. The lightest touch kills the engine. Keep the ideas coming- it's really helpful to work through the possibilities....
I'll try the jets in the mean time....

[Edited on 9/6/13 by PeteMKfazer1000]

Problem solved!!! I poured some fuel directly into the carbs whilst turning the engine over and it roared into life!! So it definitely a fuelling problem- Now all I need to do is clean out the carbs and the problem should be sorted for good. thanks for all the sound advice, this really is a great forum.

Pete