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Discussion Starter #1
Evening,
I'm nearly ready to balance my throttlebodies on the bike.

If the morgan carbtune turns up tomorrow then I'm going to give it a go,am I correct in the assumption that the IAC valve is disconnected ? along with whatever connections are to the airbox (which is removed )
Thanks
 

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Per the OEM service manual, they suggest to keep the IACV connected and TEE into those hoses.

However I find you will get better results by connecting the balance gauges directly ............ but here's the thing; on that generation, it needs air through the IACV ports to be able to run; it simply will not idle with the the gauges connected directly to the ports as there is insufficient air with the throttles 'closed' (they are not ABSOLUTELY closed -balancing itself is actually adjusting the 'closed' position of the butterflies); so you have to open the throttles slightly in order to maintain running. I use a small shim in the throttle stop to achieve that.
 

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Discussion Starter #3
Thanks DEcosse for the advice,this forum is great for first time triumph owners !

A theoretical question ? If the iacv had failed could that be a reason my bike wouldn't tick over ? I'm hoping that a throttle body balance will cure it first though.

I removed and cleaned the iacv and saw the stepper valve moving when I turned the ignition on so I'm hoping its not that.

So I can get a better understanding......what actually causes the throttle body synchronisation to go out ? Also in the act of throttle bodies being "out" of synch does this cause the iacv to struggle to maintain an even tickover ?

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2001 in the UK is a gen1 or gen2 engine, DEcosse?

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I thought so. The USA and rest of the world sometimes don't line up on model year changes, which is why I was asking.

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A theoretical question ? If the iacv had failed could that be a reason my bike wouldn't tick over ? I'm hoping that a throttle body balance will cure it first though.
Yes

So I can get a better understanding......what actually causes the throttle body synchronization to go out ?
Usually valve play adjustment requires throttle body balancing. That's pretty much it apart from the screws moving by themselves.

Also in the act of throttle bodies being "out" of synch does this cause the iacv to struggle to maintain an even tickover ?
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Yes. It can specially if the amount of air going through the TB at idle is not sufficient. IACV is just a trimming of the idle air flow.


Fred
 

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Gen 1.


The big advantage of DEcosse method is that it will eliminate the IACV from the equation. And BTW it's indicated that way in the manual.


They also state at the end of the procedure (last Note):


Apart from that you can still emulate the IACV w/ your fingers (I did it on my 955).
Disconnect the three hoses from the IACV and old them w/ one hand between the thumb and the middle finger (all 3 at the same time) and regulate the idle w/ the index finger modulating the air flow.

This way you will achieve the same work as the ECU does and roughly maintain the idle rpm.

If you can't maintain the idle that way the problem is not the IACV. Maybe a clogged IACV hose or you connected the 4th IACV port by mistake to one of the hoses (the dead end one).


Fred
 

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In the Fuel Engine Management system the section that seems to be referred to in the last note is (seem to be):





So using TuneECU you will achieve the same result.

Closed Thottle Position: The closed voltage position corresponds to the 0 of the TPS. May be worth resetting the TPS zero.
Idle fueling: It's the idle fuel trim that corresponds to the CO rate. It's better to use a gas analyzer for adjusting this parameter.
Adaptive stepper position: allow to adjust the IACV position around which the IACV will move. There is controversy on that. My advise is the correct value corresponds to the right return to idle speed. That is modifying this value will inflence the return to idle when bliping the throttle. If it returns too fast the engine may stall. Why: because when you release the throttle the IACV will first go to this position and the adjust to achieve 1200 rpm. So if the set value corresponds to a too closed value the IACV first strangle the air flow and the start to adjust. I remember a upper value corresponds to a more closed valve. not sure though.
DEcosse will provide an average realistic value.
Long Term Fuel Trim: corresponds to a value calculated by the ECU using the O2 sensor voltage. So I don't get why this is included in a first gen workshop manual. Anyway, the value can be modified. Afterward the ECU will keep on adjusting this value by itself. I shouldn't have any impact on a gen 1 engine/ECU.




The corresponding TuneECU display (test mode) is:





Fred
 

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Discussion Starter #12
Blimey ! That is a wealth of info thanks guys,I will read and digest this and attempt today or tomorrow again to A / get tuneEcu to bloody work, and B / balance the throttle bodies without gassing myself and get back to you.

In the manner of a confession I haven't (as yet ) actually checked or adjusted the valve clearances as that process looks quite involved,is all of this other work valid with this in mind ? It's human nature to take the path of least resistance.
I'm impatient to just take her round the block once ticking over reliably just to see what she feels like and get a general feel as it's been roughly three months of fitting working when I can on her around my job.

thanks for all of the input and I will report back on my slow war of attrition !

PS Fredsprint where on earth is south britany ?
 

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Ah you're correct of course @fredsprint regarding the manual - it is the second gen S3/Daytona manual that recommends tee'ing to the IACV hoses Which itself is contradictory to the second gen Sprint manual - in a configuration that is identical to the S3/Daytona - the Sprint manual says disconnect as per the guide you posted while the S3/Daytona manual says TEE.
But of course I had recommended the best way to do it regardless.
 

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... I haven't (as yet ) actually checked or adjusted the valve clearances as that process looks quite involved
CHECKING the clearances is very simple, no different that any other engine - once you have tank and airbox off, you then just have to pop the cam cover off and check them.
It's ONLY if you have any that are out of spec that it gets more complicated*, where shims actually have to be replaced to bring back into spec (there is no 'adjustment' in the literal sense of the word - the gap is set by fixed thickness shims and if any are out of spec, the shims need to be replaced with new one of suitable size)
But again, the checking part is easy - so at the very least, you should at least do that so you can see where you are - and then make the decision whether to proceed with bringing it into spec, or deferring that project for another occasion - but at least you'll know where you are!

* The process for shim replacement is again outlined in the manual and suggests using a special tool (these are available on EBay) - but the tool is fine if you only have a few that require replacement: if any more than that, it is simply more productive to remove the camshafts.
But again, cover that base if/as/when you need to - just start with checking all the clearances and make a decision from there.
 

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Discussion Starter #15
Thanks for all of the help,I've retired defeated today as here in Northamptonshire its wet,cold, and dark.

I balanced the throttle bodies with the newly purchased Morgan carbtune - which is a great piece of kit,upon putting everything back together it now tries to tick over but at 900rpm ?

I still cant get tuneEcu to communicate with the bike,I have a gut feeling it's something simple but cant fathom out what ? I'm going to reinstall it anew on the borrowed laptop and try again another day.

A question I do have for those of you who have used tuneEcu is - once bike and programme are connected and talking to each other should I be seeing a solid green bar in the status at the bottom right of screen ? I ask this as when trying to read map from bike when the bar is solid green the progress bar skips along,but once the bar changes from solid green to flickering green it pauses and eventually times out ?

Hopefully this makes sense to you long time triumph owners from a cold and tired Englishman
 

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PS Fredsprint where on earth is south brittany ?
Brittany is the territory that was ruled by Anne de Bretagne, of which castle is in Nantes.
Sometimes called Armoric.

It's known as a celtic territory.

The funny thing is, because of treaty signed by Anne de Bretagne, there is still no toll road here (as in California BTW).

Fred
 

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I ask this as when trying to read map from bike when the bar is solid green the progress bar skips along,but once the bar changes from solid green to flickering green it pauses and eventually times out ?

Hopefully this makes sense to you long time triumph owners from a cold and tired Englishman
Cold or old? Not cold yet!
Honestly I can't tell whether it's solid green or not when downloading or uploading the map. Others may remember.
I may try though. Never had T.O.

Fred
 

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Either Carb Stix (the old mercury filled ones) or the Morgan Carbtune.
The Carb Stix have the advantage of longer columns to view but the disadvantage of getting air bubbles in the mercury.
I think the old mercury Carb Stix are long out of production but I still have mine.
 
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