[Thudone1]

After about 20 to 30 minutes of riding, the bike try's to die if I try to take off with hard exceleration ?

I have changed plug, fuel pump is working. I'm lost
Bike is 2012 500 bullet w/ 14000mi. On it.

[Arizoni]

I think we need a bit more information.

When this happens, does the engine just pause for a moment and then regain its power and accelerates OK or, does the engine lose power and continue to just cuff along?

When you do these hard accelerations, are you starting from a stop or does it happen only when you are cruising at speed and then want to rapidly accelerate?

If it is the latter, are you downshifting to a lower gear before you try to accelerate or are you just leaving it in a higher gear as you twist the throttle wide open?

Is the motorcycle in stock condition or have you changed the air inlet or exhaust system?  If the bike is not stock, what modifications have you made to it?

Has this problem come on suddenly or did it start as a minor problem and become worse over time?

Knowing the answer to these questions will help us figure out what the trouble is.

[Thudone1]

It happens on hard exceleration in 1st an2nd gear. If I keep the throttle open it will die, if I shut it an roll it slow it will stay running. Works fine on top end.
 As for mods, short exhaust( basically an open exhaust), o2 eliminator, and no air filter.
 It will do it with or with out the o2 sensor.
 It just started one day, no better, no worst.

[Arizoni]

You might want to check the fuel hose that runs from the fuel pump to the fuel injector.

These can get kinked and if it does, it will starve the engine when large amounts of fuel are demanded.

Even if it doesn't have a real kink in it, it might be a good thing to replace the hose with a new one.
They can occasionally break down internally and develop an obstruction.

If you do replace the hose beware:  The plastic outlet on the fuel pump is rather weak and it is easy to break it off.  If it does break, it requires buying a new (very expensive) fuel pump.
Also, this fuel hose is delivering fuel at 45 psi so don't use a regular rubber fuel hose.  It needs to be one that is made for fuel injected systems.

I know the Continental GT often has this problem with its fuel line but I haven't heard of many instances of it on the 500 cc UCE's but it's worth a look.

[Arizoni]

You might want to check the fuel hose that runs from the fuel pump to the fuel injector.

These can get kinked and if it does, it will starve the engine when large amounts of fuel are demanded. (Like at wide open throttle.)

Even if it doesn't have a real kink in it, it might be a good thing to replace the hose with a new one.
They can occasionally break down internally and develop an obstruction.

If you do replace the hose beware:  The plastic outlet on the fuel pump is rather weak and it is easy to break it off.  If it does break, it requires buying a new (very expensive) fuel pump.
Also, this fuel hose is delivering fuel at 45 psi so don't use a regular rubber fuel hose.  It needs to be one that is made for fuel injected systems.

I know the Continental GT often has this problem with its fuel line but I haven't heard of many instances of it on the 500 cc UCE's but it's worth a look.

[gizzo]

Blocked fuel tank cap vent?

[Guaire]

I bet Arizoni is right.

[Thudone1]

Gizzo was right, can't be leave it was that simple

Thanks for the help!!!!

Arizoni I'm going to change the fuel line also. New line won't hurt.

[Blairio]

a wiser person than me on this forum advised that I gently warm the fuel pump end of the stock fuel line with a hairdryer before trying to ease it off the plastic spigot coming out of the fuel pump.  This worked well, and the line came off easily. I then repeated the process when replacing the fuel line.

[gizzo]

Happy days 

[jefrs]

The other trick they play is blowing the fuse on the fuel pump or the pump connector simply falling off leaving you with gravity feed. Check you can hear the pump, it should have enough suck to clear the breather.

The oem fuel hose is genuine rubbish, mine dissolved in petrol but cost pennies to replace with real petrol hose. Jubilee clips are not for petrol hoses, the small ones do not close circular, hence they leak. Proper petrol hose clamps (stainless 720° with a nut and bolt) are cheap too.

Removing the hose required removing the Jubilee clip out of the way and then gripping the hose with gas nut pliers and turning the hose to break the seal, then pushing it off from its end. The gooey mess oem hose just slipped off,  the pukka petrol hose went on easily with my fingers but wanted some brute force to get it off again, they need pushing from the end to compress them and open the hole, if you pull they stretch and close the hole.