Limiting to 4,500 revs

  • Thread starter Thread starter Chris7
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Chris7

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Following a miss fuel - ::blast, I know dick, my bike will not rev above 4.5k revs, or go abouve 75 mph.
It runs fine on 1/2 throttle, but open it it up at any revs and it splutters and back fires badly. Keep it steady and it will ride fine.

I have since added at least 30 litres of PETROL, I have disconnected the battery to try to do a reset of the ECU. I have tried to short out the side stand (white and Brown) but this makes no difference. Also no warning lights.

Any ideas would be really appreciated, geting a bit bored with only 1/2 throttle, on the good side the ecconomy is brilliant on 1/2 throttle, just like a diesel:JB
 
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When you disconnected the battery did you do a throttle re-set?

Wind the throttle slowly open and closed, taking about 3 seconds, do this three times.

I'd run the tank to empty and refill too.
:comfort
 
You say that you've disconnected the battery to reset the ECU, but to reset the throttle posn sensors I think you need to turn on the ignition, (but not start engine) then open throttle fully 3 times. Ignition off, then restart.

If the bike ran for a while on diesel (?) one or more of the plugs may be sooty, so could be worth inspecting these and cleaning them.

I don't think diesel will have done any permanent damage (unlike petrol in disel engines :eek:) to the injectors, engine etc.
 
Could well be the secondary plugs, ie the ones at the bottom. I think the engine mapping is such that they only fire at large throttle openings. When one of my secondary coils broke down, the symptoms were much as you describe. Make sure you reset the TPS properly first.
 
I pumped 32 litres of finest French (BP) diesel into my 1200GSA.

After getting it out, I filled it with 32 litres of finest BP 97 RON. It then took three tank fulls (in excess of 100 litres) to fully clear the diesel out of the system, clouds of smoke etc.

I did though have no trouble hitting the red line in all gears, once I had got it over the first mile or so of belching and farting out of the way.

Diesel coats the inside of the tank, the fuel filter, the fuel pump and the injectors, but has no effect on the ECU, so no need to remove the battery. Similarly, it has no effect on the sidestandswitch. Not least it is heavier than petrol so it will keep sinking to the bottom of the tank, meaning that it gets sucked through ahead of regular petrol.

What else did you do in the diesel fun?

Did you try running the bike, before draining the diesel or before it was all out? If so, I would simply bet on your plugs being fouled. They are difficult to clean properly. Buy some new ones.
 
PS

One tip.

If you by-pass the the fuel pump controller (see the sticky) you can run the fuel pump direct from the battery.

Disconect the 'fuel out' pipe, then add a length of piping to it. Stick the end of extended pipe into a suitable container, connect the by-pass to the battery and pump away.

Some time later.... one empty tank.... except for the nasty oily residue... Splosh in some regular fuel, slosh it around (do not drop bike on floor) then let it settle (over night if possible) and pump it all out.

Refill with prime petrol.

Do not try to start the bike during this process, all you will do is foul the filter, the injectors and the plugs.

Hot tips:

You will need a lot of containers.... or one, which you will have to empty a lot.

Turn off pump before container is full.

Dispose of fuels responsibly (do not pour down a French drain :augie).
 
When and how do you do the throttle reset, after the re connection with ignition on?
 
I removed the plugs after, cleaning and replacing, no difference seen. Its now had 4 new tankfulls, runs great up to 1/2 throttle,
 
More Limiting observations

I do feel this is like a electronic, limp home, mode of fault. Someone suggested the side stand micro switch, but I have shorted the brown and white leads to no avail, same problem exists.

The bike was perfect up to the miss fuel, then after the full clean out, it was like this. Also checled all the fuel pipes they look fine, fule pump connectors look fine.:confused:

IS IT POSSIBLE TO READ ANY FAULT CODES WITHOUT A DEALER DIAGNOSTIC TOOL, I DO HAVE A EOBD READER FOR CARS, WILL THIS WORK:type
 
Does any one know if the manual refer to limp home or rev limiting
 
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Check to see if the O2 sensors havent been coated with crud also. That may be tricking the ECU also.

Gonz.
 
Have you actually done the throttle position reset as others advised earlier in this thread?

(Ignition on but don't start, open throttle to its stop and close three times, ignition off, ignition on, start the engine)
 
If you can limp to my house (York) I'll plug my GS-911 diagnostic in and see what's recorded, maybe nothing as it was just a miss fuel, but we'll see :comfort

contact me - martin dot ebdon at ntlworld dot com
 
Bump - Not heard form Chris7 so guess he hasn’t seen my post.

Chris ring or text me on.

0795
179
6268

I’m in this evening.
 
Diagnostics failed to show probelm

Many thanks to Martin (ebbo), his GS911 diagnostics shows any diagnostic faults.
A few showed that I had created in trying to fix the original problem, but Martin cleared them all down.:comfort We checked the Lambda sensor's, they looked fine, we set the throttle after another ecu reset. Tried the bike, no difference.

Its still working on 1/3 throttle only, if you try full throttle it backfires and miss's, if you try to go over 5k revs its like fuel starvation, the same in any gear. Keep it below 5k revs and less than 1/3 throttle and its perfect.

I will try the plugs and fuel filter next, any other ideas suggested would be welcome::confused:
 
Chris7 said:
I will try the plugs and fuel filter next, any other ideas suggested would be welcome:. : confused
Click to expand...


Fuel, Spark and Compression are the three things you require.

Does the throttle actually fully open the throttle butterflies? You could try removing the rubber air inlet elbows to the throttle bodies and fully open the throttle whilst observing the butterfly plates opening. At full throttle setting they should obviously be fully open. That will eliminate the mechanical throttle action from your diagnosis.

I believe the fuel filter is situated inside the fuel tank, but again it is a component worth checking in case a partial blockage is limiting fuel flow. Maybe a shot of Redex/Dryfuel/ProFST etc in the tank might help to ensure the fuel injectors are clean and atomising the fuel properly.

Perhaps your Fuel Pump Controller is faulty and not allowing the fuel pump to operate at sufficient pumping rate to deliver full fuel flow at max throttle ?? Maybe temporarily swap the component with a mate then test ride and see if the fault disappears?

New spark plugs are cheap enough to eliminate by fitting new, try www.sparkplugs.co.uk for new ones. Check the stick coils for cracks and obvious damage, especially the secondaries beneath the cylinders which are prone to corrosion and internal cracking. I've replaced one myself due to internal corrosion of the laminated steel core causing big cracking although the coil checked out electrically with a multimeter.

As for compression, valve clearances are important. Easy to check and eliminate.

Use a GS911 to synchronise the throttle idle steppers when stopped, then using a manometer, carbtune or twinmax balance the throttle butterflies at 4000 rpm to set smooth high rpm operation.

If it still wont rev after all this, I'd suggest a main dealer.:nenau
 
A quick blip of the throttle showed it to fluff as soon as revs tried to go over something like 4000rpm and Chris said it generally doesn't feel as though its running quite right.

As we discussed Sunday, new plugs will be tried and see if that does any good, fingers crossed.
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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