2009 zip cutting out only on full throttle

Hi .

I need some help, my sons 2009 zip 2t has had a 70 big bore kit, race exhaust, big carb fitted up rated spark plug a red cdi, new stater and big carb fitted and he has been running it in for around 200 miles but on full throttle it cuts out will restart straight away and will ride well 25/ 30 mph but as soon as full throttle it cuts outs.

We tried jetting it from 68 up to 96 and back down but still the same, does anyone have any other ideas on things to check, sadly I have not rode it yet myself to see if its boggs or more electrical cutting out.

Oh its got a mixture of two different weight rollers fitted two?

Any help would be great, or I will start back tracking and fitting standard parts back on it

 

Not enough fuel in the float bowl. Check the float height.
Also check the flow rate from the vacuum tap on the tank

 

Hi .
Thank you .so how is the best way to check that.
Take the fuel pipe off the carb and crank the bike.

Is this why some people damage the diaphragm in the fuel pump and block the vacuum pipe off the carb so the fuel runs faster and full on under gravity rather than vacume .

Reason I say this, we bought a ital. jet fomula 50 lc as a restoration project and this has been done on that?

 

Bodge job

 

Thank you .so how is the best way to check that.
Take the fuel pipe off the carb and crank the bike.
Take both pipes off the carb, put the fuel pipe into a clean empty jar, suck on the vac pipe and hold the pressure on it (stick your tongue in the end). Let it flow for 15 seconds then measure the amount of fuel in the jar and check against the specs.

Is this why some people damage the diaphragm in the fuel pump and block the vacuum pipe off the carb so the fuel runs faster and full on under gravity rather than vacume .
No, over time the vacuum diaphram does degrade and either stops working in the open or closed position.

Reason I say this, we bought a ital. jet fomula 50 lc as a restoration project and this has been done on that?[/QUOTE]
Bodge job

 

Hi.

So the saga continues.

Been playing with the ped we have good good fuel etc but still wont go on full throttle or past 30 put standard rollers back in and new air filter playing with jets from 68 up but it wont go on a 100 plus .
jet.

Tried the muxture screw from half a turn to around two full.turns out but still no different really going my head in now help help

 

Bodge job[/QUOTE]

I had a tap diaphragm degrade and the engine was sucking fuel down the vacuum pipe, as well as the fuel pipe and it ran rough and not full revs

 

May be worth trying a new fuel pump .