Fast idle in warmer temps

[Will14]

Hi all

So I have had my bike in with Motrac Race Engineering this last week and have had a custom map done, the difference is noticeable from idle all the way through to the top end, power delivery is smooth all the way and my rough idle has been cured, she was far to lean at idle which has been sorted and the results are 108hp with my standard set up other than twin Beowulf end cans, which is not too bad

My question is, my fast idle is not currently working despite everything being in spec, will this be due to the rise in ambient temperature at the moment? It was 18 degrees here at 9am this morning and the bike lives in a garage which again is pretty warm at the moment

I don't want to start tinkering again if this is normal so any views would be appreciated

Thanks

Pete.

[hard road]

I wouldn't worry about it too much just yet if the bike starts good. 

[Speedy1959]

At the moment my fast idle is barely a fast idle and then it only lasts around 10 seconds max from cold..
I am assuming its due to the warmer weather now..

S.

[KiwiCol]

At the moment my fast idle is barely a fast idle and then it only lasts around 10 seconds max from cold..
I am assuming its due to the warmer weather now..

S.

Yep, that's what is does on the upsidedown part of the world too, now it's a bit cooler it runs for about 15 sec before it's back to 1100.   I wouldn't worry about it Pete, the bike has been tuned & sorted, so leave it be would be my recommendation. 

They could have adjusted the start up fueling so there's no need to have the fast idle come in?

[Will14]

Thanks for the replies much appreciated

I'm sure that it will work once the temperatures get back to normal, if there is a normal any longer! It's just one of those that I would like to know if it is working or not, there must be a way of fooling the ECU to test it, but will think about that again

The fueling has definitely been adjusted at idle, looking at the map file adjustments it seems the bike was quite lean low down but quite rich at higher revs, starts first push of the button and runs at approx 1000 rpm then takes approx 30/60 seconds for the revs to get up between 1100 & 1200 rpm

Thanks again

Pete

[grog]

Will, works for 30 secs at my current  around 12 temps, Summer never does. All good Mate.

[Will14]

Will, works for 30 secs at my current  around 12 temps, Summer never does. All good Mate.

Thanks Grog, that's pretty reassuring all should be good 

[hard road]

all bikes are set up as lean as possible from the factory so they need choke (fast idle) richer mixture to start, but yours as had the mixture richened up so won't need it like a standard 1400.

[Hooli]

From memory of reading the workshop manual the fast idle is a two stage process. 30 secs of increased revs and two mins slightly increased. There's a couple of trigger points based on temp which I can't recall.

Mine does much the same as yours, which is good as I've had to setup the fast idle stuff recently after having the TBs totally in bits.

[Will14]

At the moment my fast idle is barely a fast idle and then it only lasts around 10 seconds max from cold..
I am assuming its due to the warmer weather now..

S.

Yep, that's what is does on the upsidedown part of the world too, now it's a bit cooler it runs for about 15 sec before it's back to 1100.   I wouldn't worry about it Pete, the bike has been tuned & sorted, so leave it be would be my recommendation. 

They could have adjusted the start up fueling so there's no need to have the fast idle come in?

@KiwiCol you are spot on there. I had the PC disconnected yesterday while I was tinkering & started the bike, the cold start kicked in straight away, reconnected the PC and tried again much later in the evening and no cold start

I have now made a copy of the custom map and reduced the fuel changes at 500 to 1500rpm only at throttle position zero and this evening the cold start kicked in with the custom map, I only changed the fuel to the standard zero setting at these increments

This got me thinking, if I was to change the same settings to minus numbers at throttle position zero from 500 to 1500 rpm would this fool the cold start into kicking in when the bike was warm? I was originally under the impression that the cold start only worked inline with the ambient temperature, but not so sure now? 

Pete

[Hooli]

Cold start is mostly based on the oil temp rather than ambient temp.

[Will14]

Cold start is mostly based on the oil temp rather than ambient temp.

@Hooli thanks, Ah right I see, do you know how and where the oil temp is measured & I'm guessing that the ECU must be preventing the cold start from functioning with the richer mixture in the custom map then?

I'm still trying all sorts to find the cause of the bad running issue I have, even after getting the custom map done I still have a bit of a running issue. I can replicate it now and it always happens at 60mph in 5th & 6th gear at a tad under 3000rpm - crack the throttle wide open and the bike stutters for a few seconds then pulls like hell again, not a nice feeling mid bend or when going for an overtake! I have pulled most of my hair out trying to cure this, almost at the point now where I am about to give up and get rid, last week I had decided enough was enough but had another think and have decided to give it one last push to try and fix before selling   

[Hooli]

The oil temp sensor is behind the barrels, just by that Y shaped oil pipe. It's got black and black/white wires from memory. The wiring goes up the side of the airbox to a plug next to the frame tube.

Mine failed without causing a code, but it was giving a resistance about 10x higher than it should so my bike was mega rich. There's values in the workshop manual to test against.

I assume you've tried unplugging the clutch switch when the bike is running? I've seen the springs in the fail so the bike stays on the starting map. When that happened to me mine would cough before it went if given a handful.

[grog]

Reckon Hooli might have a good idea, clutch switch.Easy to check, sit with bike in 1st gear, as you slightly pull in or let clutch lever out slowly, you can hear/tell different mode kick in, at least can on mine.

[Will14]

The oil temp sensor is behind the barrels, just by that Y shaped oil pipe. It's got black and black/white wires from memory. The wiring goes up the side of the airbox to a plug next to the frame tube.

Mine failed without causing a code, but it was giving a resistance about 10x higher than it should so my bike was mega rich. There's values in the workshop manual to test against.

I assume you've tried unplugging the clutch switch when the bike is running? I've seen the springs in the fail so the bike stays on the starting map. When that happened to me mine would cough before it went if given a handful.

@Hooli thanks again for the information, I fitted a new clutch switch last year - supposedly a genuine Suzuki item. I did have a look at it a bit closer this evening and one of the wires going into the spade connector didn't look the best so chopped them both off and fitted new terminals, just to tick that box

One thing I have noticed, with the ignition on but the bike not running if I pull the clutch lever in, then let it out there is a small sound from the pump in the tank as if its getting a signal, I presume that this is the way it should be 

I will try and get the oil temp switch out tomorrow & test to see what readings I get, possibly easier said than done, looking at its position it may me fiddly with my shovel sized hands