[guyver1]

Yes the title is right EJECTION

I have a 2002 Speed Four, that overnight has developed a fault, where it is ejecting about 30 miles worth of fuel per tank out of the exhaust

Its been to 2 main dealers who both said its number 3 cylinder with the valves not closing

I stripped and rebuilt the engine and found zero problems with the valves
I put new plugs in and checked the coils all of which are fine

Ive just ordered a replacement IACV as mine has definately packed in as the insides have fell apart

I know the IACV controls the choke and wondered if this was the cause, but the bike runs as sweet as anything, no high revving, no hunting for fuel or anything

anyone got any more ideas what could cause it??

 

[Will]

I don't know what else it could be, but if the bike runs fine, I doubt it's the IACV. But, if you didn't find anything else wrong, I guess maybe it could be.

 

[BombFactory]

I can't see how anyone would have thought the problem was valves. If there was something drastically wrong with the cams and/or springs to keep the valves open to use that much fuel, the piston would have had a hole blown in it long before you noticed a decrease in MPG. Also, the engine would run like absolute junk, backfiring out the intake and having no compression in that cylinder.

As Will said, if the engine idles and runs great, I can't see how it would be the IACV.

Have you checked to see that there aren't injectors sticking open? What did the old plugs look like, and what did the pistons and combustion chambers in the head look like?

 

[pete2]

I think I'm having a similar problem. The bike runs fine, but the fuel consumption is appalling. Haven't had the head off, but the plugs are black-ish. Sometimes when starting it fouls a plug. It seems to be running really rich, judging by the smell of gasoline at the exhaust. I had a dyno tunder PC map, which I adjusted quite a bit leaner, but it didn't change a lot. Now I've bought a professional quality AFR meter, I'll have to install it and see what it says.

 

[guyver1]

Cheers for replies everyone

quick update

I bought an OBD reader as my car through up a fault the other night, I took a chance and tried it on the bike

I got 3 codes which all pointed to the IACV
I fitted a new one just, and bike is running fine and idles a lot better, the faults are now cleared

so IACV was a certain problem part

The head was spotless on all valve openings and the valves were all fine too except 1 of them which had a minute black spot on it which came off when i reground all the valves

the valve gaps were all within tolerance, some high some low, but nothing to really moan about, the bike still stinks of fuel and exhaust fumes are wet and black

NO oil loss and NO coolant loss

I have no more dealers i can trust to look at my bike so im stuck

can the throttle bodies go out much on there own??

 

[themaster]

Is the temp sensor reading something sensible? They can get shorted out and read either very high or very low, the latter making it run rich and lumpy.

 

[guyver1]

Is the temp sensor reading something sensible? They can get shorted out and read either very high or very low, the latter making it run rich and lumpy.

temp is fine mate

 

[Will]

OK, I suspect a mapping issue now. It's not a huge deal, since you are riding a Speed 4 and there just aren't too many maps for them. The California air injection map seems to work pretty well for a whole lot of people. Once you have a map you like loaded, then start lowering the fuel idle trim. There's a balance on these machines between leaning it out to the point it's a PITA to ride and having it puke fuel all the time. Since you had a screwed up IACV, the chances your fuel idle trim is all screwed up is about 100%. I'm assuming you have TuneEdit with all this. If you don't then you'll have a trip to the dealer ahead of you, and they SHOULD adjust the CO properly. Another thing which will waste a whole lot of fuel is throttle bodies out of synch. So there's another adjustment which you probably are in need of. Beats me why the inside of your motor wasn't all carboned up. For what it's worth, my TT600 would get less than 20 miles per US gallon at the track, so if you are really whipping it, you'll see lousy fuel mileage even if it's perfect.

 

[guyver1]

OK, I suspect a mapping issue now. It's not a huge deal, since you are riding a Speed 4 and there just aren't too many maps for them. The California air injection map seems to work pretty well for a whole lot of people. Once you have a map you like loaded, then start lowering the fuel idle trim. There's a balance on these machines between leaning it out to the point it's a PITA to ride and having it puke fuel all the time. Since you had a screwed up IACV, the chances your fuel idle trim is all screwed up is about 100%. I'm assuming you have TuneEdit with all this. If you don't then you'll have a trip to the dealer ahead of you, and they SHOULD adjust the CO properly. Another thing which will waste a whole lot of fuel is throttle bodies out of synch. So there's another adjustment which you probably are in need of. Beats me why the inside of your motor wasn't all carboned up. For what it's worth, my TT600 would get less than 20 miles per US gallon at the track, so if you are really whipping it, you'll see lousy fuel mileage even if it's perfect.

only 1 map in the UK for the speed four, and thats bang on

tuneEdit i've not heard of before, but ive just ordered a dealertool (www.dealertool.co.uk) and that runs a check on pretty much everything on the bike, and tells you in a nice laptop display about your throttle bodies

if there out, the MOT is due next week so ill get them to adjust them for me then

Ive got a sneaky feeling the valve clearances are out

 

[guyver1]

quick update

Ive checked the valve claearances and found that 9 out of 16 were out

mostly by a tiny amount, but did find 2 that were out by .5 and .7 which is a hell of a lot

ordered new shims and will get them fitted, then try the Dealertool to see how the throttle bodies are

I feel I'm getting close now LOL

 

[BombFactory]

quick update

Ive checked the valve claearances and found that 9 out of 16 were out

mostly by a tiny amount, but did find 2 that were out by .5 and .7 which is a hell of a lot

I'm confused. Which way are the valves 'out'? Too tight, too loose? Could you clarify your measurements for us? Have you done a leak-down test to see if you even have leaking cylinders? Another question that hasn't been asked is: what kind of mileage are you getting out of a tank of gas when riding conservatively.

 

[Calliway]

Interesting thread.

FYI - Fuel injected bikes don't have chokes. Your IAC advances the throttle at idle when your throttle is off so that the bike can continue to idle. It doesn't choke anything.

As far as fuel, how where the injectors and injector seals? It sounds like they are either slobbering or they are not sealed properly. For you to get fuel in the exhaust you would need to have fuel leaking into your cylinder on your exhaust stroke or have a major unburnt amount at ignition.

If that were the case you would also be going through plugs like crazy. If your injectors are slobbering then you will always have a trickle of fuel leaking into the cylinder. It would also be finicky to start.

I'd check those valves then look to your injectors if they don't cure your issue.

Good luck!

 

[guyver1]

I'm confused. Which way are the valves 'out'? Too tight, too loose? Could you clarify your measurements for us? Have you done a leak-down test to see if you even have leaking cylinders? Another question that hasn't been asked is: what kind of mileage are you getting out of a tank of gas when riding conservatively.

Too tight mate, sorry should have said

didnt have any that were loose atall

Im guessing that the tight ones (.5 &.7 both on the exhaust side) were not coming far enough back to make an airtight seal and letting the fuel through

all the valves were reground by myself after a dealer said that they were causing the problem, but when the engine was stripped all the valves were fine, I just reground them to be doubley sure

Ive ALWAYS got 120miles to a tank give or take a few miles

then overnight it dropped to 80miles

 

[guyver1]

Interesting thread.

FYI - Fuel injected bikes don't have chokes. Your IAC advances the throttle at idle when your throttle is off so that the bike can continue to idle. It doesn't choke anything.

As far as fuel, how where the injectors and injector seals? It sounds like they are either slobbering or they are not sealed properly. For you to get fuel in the exhaust you would need to have fuel leaking into your cylinder on your exhaust stroke or have a major unburnt amount at ignition.

If that were the case you would also be going through plugs like crazy. If your injectors are slobbering then you will always have a trickle of fuel leaking into the cylinder. It would also be finicky to start.

I'd check those valves then look to your injectors if they don't cure your issue.

Good luck!

The injectors seem fine (so far)

the plugs I replaced when the initial fault started, but the ones I took out were all nice and clean, a good light tan colour, no soot or fouling on them


The bike starts fine first press of the button since replacing the IAC but did falter a little (idling VERY low but didnt cut out) then run fine.

Soon as the shims are fitted, ill put the diagnostic tool on the bike, which should tell me if the throttle bodies are out, and if the injectors are ok too

Im not sure if the throttle bodies could go so far out over night though

like I said, one minute it was fine, next day it was spewing fuel

 

[BombFactory]

Too tight mate, sorry should have said

didnt have any that were loose atall

Im guessing that the tight ones (.5 &.7 both on the exhaust side) were not coming far enough back to make an airtight seal and letting the fuel through

Thanks for the info. I don't mean to interrogate you here--just trying to help--but there is something wrong with your measurements. It is impossible to have valves on these engines that are .5 or .7 too tight. Spec calls for a clearance range for Intake: 0.15-0.25mm and Exhaust: 0.2-0.3mm. If you did have a valve any tighter than .15 under min on intake or .2 under min. on exhaust, the clearance would read 0 and you would not be able to know how much tighter they were. There's just no way to read .5 or .7 under min, there's not even a way to read .22mm under.

If it were me, I'd run a leak-down test on all cylinders and then re-measure the valve clearance before I touched the valvetrain or did anything else for that matter. If those two valve clearance measurements are off, your others could be also. You could cause more problems by replacing shims with incorrect ones. Plain and simple, a proper leak-down test will tell you 100% if you have any leaking valves, or anything else in the cylinder.

 

[guyver1]

Thanks for the info. I don't mean to interrogate you here--just trying to help--but there is something wrong with your measurements. It is impossible to have valves on these engines that are .5 or .7 too tight. Spec calls for a clearance range for Intake: 0.15-0.25mm and Exhaust: 0.2-0.3mm. If you did have a valve any tighter than .15 under min on intake or .2 under min. on exhaust, the clearance would read 0 and you would not be able to know how much tighter they were. There's just no way to read .5 or .7 under min, there's not even a way to read .22mm under.

If it were me, I'd run a leak-down test on all cylinders and then re-measure the valve clearance before I touched the valvetrain or did anything else for that matter. If those two valve clearance measurements are off, your others could be also. You could cause more problems by replacing shims with incorrect ones. Plain and simple, a proper leak-down test will tell you 100% if you have any leaking valves, or anything else in the cylinder.

Hey no worries, all help is greatly recieved mate

the measurements I got were as follows

Exhaust =E
Inlet =I

Starting from front left as looking from the seat

E1 0.18
E2 0.18
E3 0.19
E4 0.19
E5 PERFECT
E6 0.15
E7 0.19
E8 PERFECT

I1 0.08
I2 0.10
I3 0.16 CLOSE TO PERFECT AS NEED BE
I4 0.18 AS ABOVE
I5 PERFECT
I6 PERFECT
I7 PERFECT
I8 0.08 <--------------------wrong measurement given, should read 0.13

just to be 100% sure

I checked the clearances by having the bike in gear and rocked the wheel a bit at a time, untill a pair of cams were pointing slightly forward inline with the angle of the engine (facing away from the valves). The workshop manual Im using (Triumph genuine) states I should be looking for 0.15-0.25mm on Inlet and 0.20-0.30 on Exhaust

Does this sound about right?

How do I do a leak down test, money is tighter than the clearances due to economic situation over here mate

so free sounds great

 

[yimmit]

quick update

then try the Dealertool to see how the throttle bodies are

with regards the throttle bodies there's a small note on the dealertool website saying it cant balance the throttles on Sagem injection systems which the S4 has
The tool looks like it could still be useful for checking other sensors though

 

[BombFactory]

E2 0.18
E3 0.19
E4 0.19
E5 PERFECT
E6 0.15
E7 0.19
E8 PERFECT

I1 0.08
I2 0.10
I3 0.16 CLOSE TO PERFECT AS NEED BE
I4 0.18 AS ABOVE
I5 PERFECT
I6 PERFECT
I7 PERFECT
I8 0.08

I don't see any that are .5 or .7mm tight. Intake #s 1 and 8 look to be 0.07mm too tight, and Intake #2 is 0.05mm too tight. This is not a normal wear pattern, as the other clearances aren't far enough out to cause any issues, but should be corrected. Even with these 3 being that tight, I would be amazed if 30 miles more of fuel would be used. Maybe the valves/seats on those 3 are ground too deep, causing the off readings?

To do a leak-down test, you must purchase a leak-down tester. The short answer is that it is a tool that compresses the cylinder with air and gauges how much air the cylinder leaks.

 

[Calliway]

Also a scan tool won't tell you if your injectors are out. All the scan tool will tell you is if you had a fault. You would need a scope hooked up on the trigger wire of the injectors to tell you if they were physically failing.

You would physically have to pull the injectors and look at them to see if they are dirty and weeping. If you do that you need to make sure you have a new o-ring seal for them.

Sorry, I don't know enough about the valvetrain on these bikes to be of any help there but Bombfactory is teaching me lots.

 

[guyver1]

with regards the throttle bodies there's a small note on the dealertool website saying it cant balance the throttles on Sagem injection systems which the S4 has
The tool looks like it could still be useful for checking other sensors though

Thats not a problem as I'm only looking to see if they do need balancing