Fitted the new connector and Oetker clamp, put bike back together - still the same stuttering etc.

Drained all fuel out using the extra male connector from Amazon into the line at the cylinder head, some fuel line and repeatedly switching on the ignition. I could have used Buelltooth to test the pump. Anyway, all fuel gone. (Be careful not to run the pump too long once the fuel has stopped coming out - it can overheat the pump and blow the fuse).

So now I have removed the pump - nothing obvious, but does this look OK? It's the fuel strainer sock. it is black, and was white when new, I assume.



I have the Rev-Mo pump and regulator kit which I will fit at the weekend.

Fingers crossed!

A

Back on the road - managed to get the fuel pump past the swinging arm in only 7 minutes of rotating, twisting, pulling, pushing and a final shove!

I'm stumped; having fitted a brand new Rev-Mo fuel pump, fuel pressure regulator, inline and sock filters, the bike is still the same, stuttering at 2K RPM/30MPH as if a front brake is grabbing (it isn't - cleaned and new pads fitted).

Still pulls like a train at higher revs.

Done TPS reset (shows 3.5 degrees at idle), reset AFV to 100 (it had crept down to 94.4, has been 99.4 for ages - a clue? Who knows).

Have rechecked intake seals (done <2K miles ago), all good.

Next ideas are to clean the injectors and check the throttle butterfly shaft.

I have some logs from ECMDroid to review too - finally they have amended it so you can specific where logs get stored. My S21 has no SD card and I couldn't use ECMDroid because I could not control/find where the logs went!

I have a new map coming from Rev-Mo ("Race tune for standard exhaust") - I've already swapped ECM to BUEZD (original ECM but unsure what map is in it); currently running BUE2D with a custom map that did work perfectly last year.....

Any suggestions gratefully received.

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my Uly is an 06 build, on a 08 plate . do the usual start procedure , start bike , then put jacket , helmet on and take it steady for the first 10 miles or so and it occasionally has a miss / stutter ,but once fully warmed up runs ok ,it is a little bit lumpy around 2000..2500 rpm on light load . 2800 rpm is its sweet spot, kind of ,comes on pipe / cam .
unsure how many miles yours has done , but I believe that the throttle position sensors can give problems .
hence why one of the first things you do is a TPS reset when experiencing problems.
IIRC a similar thing happened with Vauxhall Astra/ cavalier , reps cars stuck on motorway at 70mph for most of there life it would" wear out" the throttle position sensor at that point and give a false reading to ECU.
logical speaking ,only thing you can do, other than blindingly change it , is whilst doing a TPS reset is VERY slowly open throttle and check reading to insure they are a linier.

But real answer would be take it
some people have spent hundreds trying to fault find a problem
has decades of experience with Buell motorcycles

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Buell Ulysses XB12X 06/08

Barney, thanks for that - the bike only has 13K miles on it, and I have got a new TPS sensor ready to fit. I've seen stuff about worn butterfly shafts allowing air to bleed in/past but unlikely at such low miles.

I will try the slow increase/watching readings to see if there is a "flat spot".

I know the bike has run better previously, so I'm swaying towards something going "off" rather than gradual wear, if that makes sense.

Cleaning injectors can be done in situ; a few YT videos of connecting an aerosol to the inlet, disable fuel pump and run bike on the cleaner.

Given the bike runs well at higher revs, maybe a slightly iffy injector has more negative effect at lower revs?

Or is that rubbish - if it works, it works whatever the revs?

A trip to Maz is on the cards; it's just the getting there/back and there again hassle.

Hi there,
Not the same bike but injectors like yours.
I use Redline complete fuel system cleaner every couple of months and can always tell the difference once it's been done. Might be worth a try and can be done in situ without doing anything else, just stick some in the tank take it for a ride and it's done.
I think I got my last lot from Opie oils on Ebay, check round though as they do an offer on two bottles sometimes.
It ain't cheap but works a treat in mine. Good luck. Paul.

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Ride Safe & Stay between the hedgerows.

Red Line Complete SI-1 Fuel System Cleaner is it's full title.

_________________
Ride Safe & Stay between the hedgerows.

A, mine has only got 14..15 k miles on it .
always use the good stuff fuel wise, and at winter times when parked up, I put some ethanol guard/ fuel stabilizer in it . you can put too much of this stuff in and makes it run a bit crap until refuelled and diluted .
I have tried fuel system cleaners in the past with cars, but in the end found if you just use a branded good quality fuel ...v power / ultra . and use the engine and make it work , helps.
got a nice big hill locally, goes on for miles, crawl along in top gear at 30mph at the bottom then change down one gear then gently floor the throttle pedal, gets the ecu and injectors working as you climb the hill and gather speed, not many places you can hold a vehicle flat out for a couple of miles with out reaching silly speed.

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Buell Ulysses XB12X 06/08

I was going to add something like the Redline into the fuel tank as well, but direct cleaning of the injector seems a better solution.

Watch this video - I can connect at the fuel line connector (the one I broke!) and hopefully that will work well.

https://youtu.be/aDvtzg-ThZs?feature=shared

Still need to review TPS readings/grip angle to see if the TPS sensor needs replacing; can this be done in situ or is it throttle body off?

Thank you everyone for bearing with me!

A