A thought about TPS settings

[joesnomad]

I was wondering if anyone has ever looked at TPS settings and compared them on bikes that ping and don't ping, compared to bikes that get MPG in the higher 40's. As far as the 1600's go some ping some don't,some get low 30's MPG and some get High 40's MPG. My thoughts are that 05-08 as far as I know are identical motors. So as far as pinging goes I would think that they should preform theoretically identical. It has been said many times that the TPS settings are given a range that kawa says is normal. Some are set higher and some lower some in the middle somewhere. Now comes my guessing part. If at a lower TPS setting the bike pings but maybe gets higher 30's MPG Possibly a higher setting maybe the bike doesn't ping at all but gets in the lower 30's MPG. And a setting in the middle might allow for a little pinging but MPG in the upper 40's. It just seems to me that there should be some kind of consistency to the way they run being as they are all virtually identical at least from the factory. I realize that everyones riding style is a little different and altitude might play into it somehow and also gas quality. But if some of us can get mileage in the upper 40's I think that all of the bikes should be capable of it under identical circumstances. I have never checked my TPS setting but sometime I will check it just to see were its at and then attempt adjustments.

Remember that there is also an allowable range on ignition timing, valve lift, piston fit, sensor performance, and lots of other things. Two bikes could be very close, but never absolutely identical.

[blowndodge]

Joe, I've checked 3 1600 Nomads and each of the were set at 4.40 the same as mine. Even Gadget's site show a starting point of 4.40.

I've bumped mine to 4.43 and it allowed me to lower the idle and never have a stalling problem but the pinging issue is still a hit and miss proposition. I wish I could get someone from Kawa to give me the parameters of all that's affected by the TPS as Cadd had pointed out. I don't know if bumping mine a little also changed the timing too. It does add fuel but it may increase spark lead which I don't want to do. I know I ran my up to 4.59 (max according to the service manual and it ran weird with an unsteady idle and got really bad mileage.

[joesnomad]

caddman I thought that the timing was controlled by the ECU and was unajustable. Forgive me if I ask something dumb. 30 years ago I worked on cars, I got out of the field just as they were getting started with electronic ignition. I really havent worked on cars to any amount since then, and computers are way out of league. Its that the TPS thing has had me wondering for some time. I know that alot of guys on here have adjusted their TPS settings but I didnt know if anyone had done enough comparison to see if the setting of the TPS could be the culprit and solve a mystery to me anyway as to why some ping some don't and why the big discrepency in MPG. It just seemed to me that things should be more equal between bikes. But I do not understand sensors and computers on vehicles. At first thought one would think that computers would hold a much tighter tolerance on how different systems on a bike would act. My thoughts would be that if there was this much difference in cars it would sure set a trouble code. BD the three that you had checked were they all stock? Did the 3 that were set at 4.40 exibit the same symptoms.

[blowndodge]

Yes they all pinged a lot. California's premium gas is 91 octane and it's almost common place that stock Nomads in California ping in warm weather. Lots of other states have 93 and even higher octane. High altitude Nomads don't have this issue as bad as the lower atmospheric pressure lowers effective compression ration enough that pinging rarely happens.

[joesnomad]

I have ran 91 and 93 they both ping I can see no difference in the 2. Can the TPS setting be checked with out removing the gas tank. Is the timing adjustable to any degree or is it soley set and adjusted by the computer and its feed back from the sensors. Mine will ping even when the temp is in the 60's, but not as easily as when its hotter. Even 70 mph harder roll ons will produce pinging in 5th gear. 55-60 in 5th with an easier roll on will make it ping on warmer days. I hate to be a pain in the as* but I'm just trying to get as much info as I can before I decide what corrective measures I will take. I was going to do the resistor mod and still might but after looking at the way this engine gets its fresh air I might do air upgrade as well. I also realize if a power comander or a TFI unit on it would solve most if not all the pinging. however that seems to be detrimental to gas mileage. I'm not one for experimenting it just increases my chances of screwing something up, and then it costs me a fortune to get it fixed. One more dumb question only because no one around me has a Nomad so I have nothing to judge it against. When you say your bike pings, is it hard to hear or is pretty loud. Mine is pretty loud almost to the point were you might think its more like a knock. It doesnt sound like a piston slap or a bearing noise.

Originally Posted by joesnomad

caddman I thought that the timing was controlled by the ECU and was unajustable....

It is. But the factory can only make it so precise on mass production bikes. I'm 100% certain there's some variation from one bike to the next, however minute.

[blowndodge]

Joe, you will have to prop up the back of the tank about 6 inches to get your hands in there. Nothing needs to be disconnected if your careful. Gadget's site is very informative on the TPS procedure. If and if yours comes to 4.40, try 4.45 if yours is pinging as hard as it sounds.

Cadds had some ideas on bridging the air temp sensor then adding fuel which sounds interesting.

Maybe some with TFI can jump in here but I would have though that adding that unit then only turning the #2 pot up (accelerator) to stop roll on ping would be sufficient. Adding fuel with the #1 pot would clear up stalling or surging on small throttle openings. In my feeble brain the #2 pot is the ping stop pot???

[bobzinger]

BD I increased my #2 pot to 3:30 and it will stop pinging only if I crank my throttle hard. If it's a smooth increase pot #2 doesn't do anything.

[blowndodge]

does a smooth increase bypassing the #2 pot promote pinging??

Originally Posted by bobzinger

BD I increased my #2 pot to 3:30 and it will stop pinging only if I crank my throttle hard. If it's a smooth increase pot #2 doesn't do anything.

Yep. That's basically what I've experienced, though at hot temps and higher speeds it still eventually pings on mine. This is one thing I'd hoped to improve by "bridging" the temp sensor. To reduce the acceleration fuel overall, but more importantly to also to reduce rate at which the ECU must see increase in throttle position to provide acceleration fuel, then to replace that fuel (and at slower throttle movements) with the TFI.

It'll be a miracle if this works though.

[blowndodge]

Isn't that what we do though???? Maybe you'll hit a homerun???

[joesnomad]

Thanks guys for your time and knowledge.

[pablo]

Originally Posted by Blowndodge "Darksider"

Maybe some with TFI can jump in here but I would have though that adding that unit then only turning the #2 pot up (accelerator) to stop roll on ping would be sufficient. Adding fuel with the #1 pot would clear up stalling or surging on small throttle openings. In my feeble brain the #2 pot is the ping stop pot???

I have the Cobra Fi2000, so this might be different, but I turn up the #1 pot to stop popping on decelleration and turn up the #2 pot to stop pinging on hard accelleration. This seems to work. I had it set on 3/5/0 this winter, and yesterday turned up the #1 & #2 a hair. With the warmer weather I was getting a little popping in the exhause and a little pinging on hard accelleration. This fixed it for now, but I may need to tweek it some more when things really heat up. I also have a 1K ohm resistor on the air temp sensor.