My bike is running lumpy

[Kevin58]

Hi, I have just bought a 2001 VFR 800Fi-1. It has been sitting outside for at least 2 or 3 months and the fuel is probably stale, about 35% full. It starts on the button and runs ok except for feeling lumpy on acceleration, particularly in higher gears. I have topped it up with Super Unleaded (E5) but was wondering, thinking that the injectors might be a little furry, would it help to add a fuel additive (redex or something). If so, advice on which one would be welcome. Thanks.

[Grum]

My thoughts would be to first to get rid of all fuel in the tank, then fill it with non Ethanol fuel (if you can get it) then reassess the situation.

Having the bike outside for 3 months only 35% full of hygroscopic E5 fuel may mean you've absorb condensation/moisture.

Running a tankfull with some good quality injector cleaner shouldn't do any harm, as to whether it will help could be debatable, but worth a try. Having the injectors professionally cleaned, flow balanced etc. would only be a good thing to do seeing they are 20 years old.

[Kevin58]

Thanks, that sounds like good advice.

[DannoXYZ]

Luckily fuel-system on EFI bikes are sealed, so they don't have as much trouble with moisture creeping in and causing as much ethanol separation compared to carby bikes. My track car sat in garage for over year waiting for engine-builder to deliver monster engine. Started up within 5-seconds! My CBR600RR sat outside in rain for 6-months this last winter, even fell over for couple days when sidestand sunk into mud. In spring, put on charger overnight and started on 1st crank >VRROOMM<. My Ninja 250 in heated garage on other hand, left me stranded on track after 1/2-lap. Ended up having to disassemble and clean carbs by scrubbing with brushes and poking with wires in pits.

 

Yeah, run through fuel-system cleaner with healthy dose of PEA:

- Red Line SI-1
- Techron Concentrate Plus
- Gumout All-in-One
- 3M Max Strength Fuel System Cleaner #08814
- Royal Purple Max Atomizer 18000

[Kevin58]

Thanks Danno.