So I reset the TPS on my 748 recently and after sync of the TBs, I was going in to set the idle speed and CO and noticed that when I backed out the air bleeds from the completely closed position, the bike's idle didn't change at all so I put them roughly back to where they were (1/4 of a turn or so, I wrote it down before I started). Also, going through about 180 degrees of motion on the idle trimmer didn't change anything either.
I assumed the idle trimmer was overruled by the FIM chip that's on the bike, so I didn't think much of that, but the air bleeds was odd to me. The bike idles just under 1500 now, which is obviously high, so I was wondering if maybe it takes a bit for any air bleed changes to take effect? Or should it be instantaneous?
Can anyone confirm/deny my thoughts on the two (air bleeds, idle trim)?
I plan on closing the air bleeds a bit before my ride home today and see if things change as an experiment.
A good blip of the throttle should settle things in IMO...shouldn't take long.
Did you check sync after moving the air bleeds? That in itself might affect idle speed.
The way it was explained to me was the synch is the rough or major adjustment and the air bleeds were the fine adjustment for synch.
None of the bikes I've adjusted ever had the air bleeds in 'exactly' the same position after fine synching.
No help on the trim.
yeah, I did check sync continuously as I adjusted air bleeds. I just went out to the bike and realized that the air bleeds were completely closed off. Guess I never got around to backing them out to the original positions...
Guess I'm gonna have to go back and redo stuff...
I'm a little confused. Assuming the throttle is set correctly and the throttles are in sync the bike and the fast idle is off should not be idling at 1500 RPM with the air bleeds screwed in. I'm thinking either you have a vacuum leak on both cylinders (manifold gaskets maybe) or your base settings are off. As to no response to trim, without a CO meter it could take a lot before you notice a change. I suppose you could try 360o in both directions as long as you keep track of your starting point
Don't know what's up with your trimmer.
If the idle mixture is lean enough, opening the bleeds won't increase the rpm.
In that case, opening the bleeds does let more air past, but it just makes it leaner and idle rpm won't go up.
BTDT, it's not a good state of tune.
What software are you using?
thanks for the responses! I'm not using any software to adjust fuel settings or tps. Just went in and reset tps using a fluke on the pins off the ecu.
at this point, i'm kind of inclined towards a vacuum leak somewhere. I don't have the charcoal canister so the lines coming off the manifolds are capped and could be a source, but I double checked and they seem fine, i'll go back and re-insert screws where the nipples went (yes yes, bad word choice I know) to see if that alleviates things.
the bike rides fine, was getting slight backfires on hard decel but that's gone and cruise at 5k seems like it needs just a little bit more fuel, but that's being super nitpicky... Let me see if I take all that back after the ride to work in the morning though....
Ok, so she was idling great in the first part of the morning and then by the time I got to work, idle was close to 1500 again. I'm going to replace the nipple/capped hose on the manifolds with proper screws when I get home and see what happens. I know I probably should've done that in the beginning, but I get lazy. I don't have a clamp on those hoses and I'm assuming their old enough that when it gets warm, it's enough to have slight vacuum leaks (the difference in pulling them off when warm and cold is significant).
I'm not ruling out other issues, but this seems an easy first step.
That 5k slight pop pop popping seems to be real in 1st (not sure totally as I blow by 5k pretty quick in 1st), 2nd, 3rd, and 4th gears and it seems a very narrow area of operation right at 5k +/- 200 rpm or so. At some point, I wouldn't mind taking a peek at the fuel map in the chip and doing some modifications...
Do you have the FIM software?
Not sure if you can even get it anymore as they closed up shop.
Quote from: humorless dp on October 15, 2010, 06:07:29 AM
Do you have the FIM software?
Not sure if you can even get it anymore as they closed up shop.
nope, don't have it, but I was looking at the tunerpro/moates chip burner option. I understand I'll run into a few issues because of the FIM chip though. Like you said, not sure I can source that software anymore...
I won't worry too much about map programming for the time being. The house has been sucking up cash lately and I don't have much to spend on the bikes... :-\
Seems you can get it, but it is spendy...
http://www.silverbackperformance.net/fim.html (http://www.silverbackperformance.net/fim.html)
none of the fim/ultimap 1.6m eproms have the idle trimmer disabled ime. if it is an early EDT (?) you can read the file, if it is a UM091 or 211 on a green circuit board it's scrambled.
the trimmer should affect the idle noticably from one end of travel to the other, which is 270 degrees. but i have seen ecu where it has been damaged or just not working.
you should also need more than 1/4 turn of airbleed opening to make a 748 idle.
sounds wacky.
the software shown is the diagnostics, which is nla as ultimap is no more. it works the zones, but not the mapping. there is no software to work with the scrambled files.
Quote from: brad black on October 16, 2010, 04:38:49 AM
none of the fim/ultimap 1.6m eproms have the idle trimmer disabled ime. if it is an early EDT (?) you can read the file, if it is a UM091 or 211 on a green circuit board it's scrambled.
the trimmer should affect the idle noticably from one end of travel to the other, which is 270 degrees. but i have seen ecu where it has been damaged or just not working.
you should also need more than 1/4 turn of airbleed opening to make a 748 idle.
sounds wacky.
the software shown is the diagnostics, which is nla as ultimap is no more. it works the zones, but not the mapping. there is no software to work with the scrambled files.
Thanks brad! I capped the lines coming off the manifold yesterday and the idle came back nicely, so there was definitely a vacuum leak. The airbleeds are out about 1/4 turn now with the idle just hovering at 1250 or so.
I still need to take a look at the trim again, but it looks like at least one issue is resolved. I won't get a chance to mess with it for a few days, but will report back when i do [thumbsup]
thanks for the info thus far!