Bilbo's Journey

[Eric GSX1400K3]

Well, thought I'd put this into its own thread finally.  As you may know, since picking up a bad batch of fuel back in April or so, my 1402 has not been running right.

Last summary / update was:

Update on Bilbo: seems I have walked through the gates of Mordor...rechecked everything i had done again just to be sure. Talked to a few places, including wreckers re a new ECU, all said they dont have any, and were surprised if it was the ecu at all. Bloke in SA said highly unlikely, as then youd have no running or rough running at all rpm, which is not the case here.

So I checked STPS (replaced with genuine new last year) this time at the connector and removed air filter to move them to check resistance.  Turns out it was giving 2.9kOhm open and 0.8 closed, the latter being to spec, but the former should be 3.9kOhm according to the book.  So I adjusted it, but its maxxed out at 3.3kOhm open and 1.1kOhm closed.  Cycled the ignition and it showed 3.6kOhm, close enough to the required 3.9kOhm for now.  Also cycled through closed to full throttle 3 times, then fired it up, still runs rough, but admittedly it hasnt run for about 3weeks, but seemed better. Let it warm up, and the stva worked for a bit so that was good.  The backfiring was not as bad either.

Ran out of time tonight but will take it for a ride again later this week to see what difference that has made, so fingers crossed, not quite at Mt. Doom yet....

Might have to file out the slotted holes in the STP housing to get to 3.9kOhm if that has really made the biggest difference.

Fingers crossed..."

[Eric GSX1400K3]

The cause is:
- contaminated fuel, most likely water in the fuel, or stale fuel.

The symptons are:
- rough idle and poor starting, takes 2 or more goes of the button and need to hold throttle open a bit.
- when idling at ~1100rpm, opening the throttle causes stumbling and hesitation, pops though the exhaust and smells of unburnt fuel, sometimes it stalls.
- over about 3000rpm it smoothens out.
- uses a lot of fuel, std is around 5l/100km, last time i rode it it was around double that.
- had rust in the tank, all cleaned out, including fuel rail, pump and new injectors (see below)


Bike is basically un-rideable, opening the throttle it bucks and hesitates, until ~3000rpm, rolling off the throttle it backfires and pops, not smooth at all.  Closing the throttle, the revs stay high for a bit.

So now I'm going to list all the checks I have done to date, all checks against values in the Suzuki manual.

- new spark plugs, with the old ones 1 out of the 4 tested at 16kOhm, the other 3 at 6kOhm (ngk spec).
- throttle cables lubed and snap return checked, all ok, cable tension to spec, not interfering or catching on anything.
- new MAP, genuine Suzuki ex Webike Japan
- new stator and signal generator as magnet on the old one was broken
- TPS replaced about 18 months ago with genuine, setting as per manual 1100 Ohm throttle closed
- STPS replaced about 12 months ago with genuine, setting now correct at open at 3900 Ohm, was 2900 Ohm open.  Closed is now ~1200 Ohm which should be 800-900 Ohm, but I think the open setting is more important
- IAT - ok
- IAP - ok
- TOS - ok
- EOT - ok
- CKP (crank sensor, part of new stator) - ok
- CMP (camshaft sensor) - ok
- injectors - replaced with new (ebay, same part no as Bosch oem) suitable for engines up to 2000cc, matching connectors etc. New seals
- coil packs - ok
- ht leads - ok
- battery - SSB lithium, new
- compression tests ok, 165psi each pot, cold
- valve clearance, all within spec at 56000km.
- efi pump (quantum aftermarket), cleaned out teabag, external hp filter and fitted new inline lp filter as well. Flow rate is 1300ml/min, spec is 1200ml/min, pressure unknown, but reg seems ok, replaced with the old one for the time being.

Next things to check:
- smoke check for any cracks or leaks, can also use carb cleaner around intake when running as suggested
- exhaust leak at header exiting block

Failing that, do I need to look at burnt valves, or retiring the engine?

I'm open for ideas, I don't want to retire or break the bike, I'm sure it can be fixed, just need to find out what is causing this rough running...

Started it up yesterday after putting thr rebuilt efi pump back in, no change.
 

[Eric GSX1400K3]

Will also work out a way to check fuel pressure (cheers Grog for the reminder)

[Pommeroy]

Eric, are you on any non-14 forums? Although there's been plenty of suggestions on here, I wonder if fresh minds may come up with something if you describe the symptoms...they won't be limited to the 14.

Just a thought.

Failing that, know any really good bike mechanics?

[Hooli]

I can't see it on the list & can't remember if we've suggested it.

Clutch switch? if they stick on the starting circuit etc works fine, but it'll be running a different fuelling & ignition map. I know when I bypassed mine as a temp measure years ago it'd backfire twice every time I gave it some throttle & sounded like someone firing a shotgun behind me.

[Eric GSX1400K3]

Thx, so other things to check now (adding to my list)
- pairs, even though checked them twice already
- TRE thats been fitted for ages, will take it out of the loop and see if any difference
-timing, when i checked the clearances, the marks were not as per manual, but cam lobes were correct for checking clearances.
- clutch micro switch

[KiwiCol]

Eric, just been reading xdiavels post, couple of things seemed to pop out, You have a TRE fitted & I think I once read Bilbo has a full Akra exhaust.  Pretty sure I recall @seth saying if you go full Akra exhaust you need to have the bike tuned.  Could be the combination of the TRE & Akra that's giving you the issues. PC-V & Autotune, else take it to a tuner.

[seth]

Eric, just been reading xdiavels post, couple of things seemed to pop out, You have a TRE fitted & I think I once read Bilbo has a full Akra exhaust.  Pretty sure I recall @seth saying if you go full Akra exhaust you need to have the bike tuned.  Could be the combination of the TRE & Akra that's giving you the issues. PC-V & Autotune, else take it to a tuner.

The number of folk still don't get it these bikes need a remap if any fueling is changed
Some get away with and endcan swap but anything more needs the fueling adjusting in some way.

[Eric GSX1400K3]

Cheers guys, yes it has an Akra 4 into 1 and a TRE. The exhaust was on it when I bought it 6 years ago, and I remember seeing a service invoice (that i can't find now, even though i have the original delivery booklet and receipt from 2003) that included an ECU flash tune. Bike has been running fine up until I got some dodgy fuel in it.

Will remove the TRE from the circuit and test.

[Eric GSX1400K3]

Eric, are you on any non-14 forums? Although there's been plenty of suggestions on here, I wonder if fresh minds may come up with something if you describe the symptoms...they won't be limited to the 14.

Just a thought.

Failing that, know any really good bike mechanics?

yes, I've been talking to my BMW mates and I'm lucky, my neighbour and friend is also a mechanic.

[KiwiCol]

Well, for the bad gas, I think you've put in a new HP pump & filter & new injectors, so all that's left is the fuel line & fuel rail. Can the rail be back flushed / cleaned out internally in any way?  New fuel lines shouldn't be a problem or just check they're not restricted. 

If you have the original HP pump & filter, have you done the HP filter bypass?   if not, Bilbo may be a good candidate for it. 

[Eric GSX1400K3]

Thanks Col,

Yes, rail cleaned out, hp filter bypass done a while ago, works well, just cleaned it out again on Sunday as well as the internal in-tank hp filter that is bypassed.  Lines after the filter are free and clean.  This weekend will be checking for air leaks.

I did notice last night that the header pipe for #1 is sitting very close/touching the lh frame tube that has the compliance plate on it, hopefully that hasn't rubbed through, the Akra is very thin wall tube...

[grog]

You and Xdiavel bikes,just  dont make any sense. I try to figure. Thats how ive paid my bills forever, fixing motors. These 2,just not playing a normal game😡😡

[Eric GSX1400K3]

Will get to the bottom of this im sure. Header pipe on #1 and frame tube

[Eric GSX1400K3]

Well, compliance plate hasn't rubbed through the #1 header pipe...yet.


Took the exhaust headers off #1 to #4 and had a peek inside the exhaust side.

I'm no expert, not sure what the white stuff is, all I know is black = rich, grey = lean, brown = good.  Can't see much brown, but lots of black and very light grey.

Cylinders 1 to 4 in photos below



Edit: looking at the valve stems, they are white, will try a closer look inside tmrw and swap injectors.