Running Hot & Rich

[Kiwi_Roy]

My 2001 is using way too much fuel, with the regular ECU it's barely doing 20 miles to the USG on the highway and it runs very hot in city traffic.

Is it possible to run hot from being too rich as well as too lean?

 

BTW is there any standard spot for measuring the engine temperature e.g. a point where I could attach a thermocouple and compare to the normal reading.

[Tom M]

What is your TPS reading at idle and how are the air screws set? Have any modifications have been done to the engine, intake or exhaust? Do you have a PCIII? Obviously something is seriously off if you're getting 20mpg.

 

If you could find a local Guzzisti or dealer with VDST software or the factory AXEONE diagnostic tool you can check to see what temp the ECU is seeing from the head temp sensor, what angle you throttle is at idle and wide open, and what the idle trim is set at. A trip to Moto International in Seattle would surely fix your problems but it looks like a bit of a haul for you.

[Kiwi_Roy]

What is your TPS reading at idle and how are the air screws set? Have any modifications have been done to the engine, intake or exhaust? Do you have a PCIII? Obviously something is seriously off if you're getting 20mpg.

 

If you could find a local Guzzisti or dealer with VDST software or the factory AXEONE diagnostic tool you can check to see what temp the ECU is seeing from the head temp sensor, what angle you throttle is at idle and wide open, and what the idle trim is set at. A trip to Moto International in Seattle would surely fix your problems but it looks like a bit of a haul for you.

Thanks for the response

The TPS has been set up according to the experts, 150 mV at fully closed 450 at idle if I recall correctly.

Intake has K&N filter but no top cover (elephant trunks).

The exhaust is standard crossover but with Mistral carbon fiber mufflers, they look like MG07 used on Griso. I believe the PO had high compression pistons fitted.

I do have PCIII but if anything when connected it seems to run hotter still.

You gave me an idea, I will measure resistance of head temperature sensor so I can put an actual ° number, do you have a temperature or Ohms in mind? e.g. is 120°C hot?

 

I have orderd a MyECU from Cliff Jefferies and I should have it in a few days, hopefully that will help.

[Tom M]

Your TPS at idle should be around 530mV. If it isn't that's at least part of your problem. If you can't get everything adjusted right per the pinned method here's an easier alternative that has helped a lot of us get our Guzzis running right.

 

Step one - Set your valves to world settings (.15mm/.006" intake, .2mm/.008" exhaust)

Step two - Set your air bleed screws to open 1 full turn

Step three - Synch throttle bodies at just off idle (around 1800 rpm)

Step four - Set idle to 1100 using left idle screw adjuster only

Step five - Set TPS to 3.6 degrees (530mV)

Step six - Ensure idle trim is set to zero. This requires an AXEONE dealer tool or VDST software.

 

With the mods you have you will run lean without a PCIII or MyECU. Do you know what map your PCIII is running? If not consider saving it to your PC then loading the gh67 map from the fileshare section of this site. Many of us have run that map with good results.

 

I don't know what the head temp thresholds are but they have been posted here in the past.

[GuzziMoto]

My 2001 is using way too much fuel, with the regular ECU it's barely doing 20 miles to the USG on the highway and it runs very hot in city traffic.

Is it possible to run hot from being too rich as well as too lean?

 

BTW is there any standard spot for measuring the engine temperature e.g. a point where I could attach a thermocouple and compare to the normal reading.

Supposedly it is not possible to run hot from being too rich, and I tend to agree. Everything I have read on temp says that max temp is a little above to 14.7:1 and then it drops on either side. That does not take into account fancy lean burn combustion chambers or anything like that.

What is possible is to have crappy fuel mileage from being too lean. I am not saying that I know you are not too rich, but just because you have crappy fuel mileage you can't just assume that you are too rich. Once you start leaning out the mixture past the point where power starts to suffer fuel mileage can go down hill as well since you end up having to open the throttle up more then you should just to go however fast. Basically you can lean it out past the point of efficiency.

 

It sounds like you have a set up issue or something is out of wack.

[Kiwi_Roy]

What is possible is to have crappy fuel mileage from being too lean. I am not saying that I know you are not too rich, but just because you have crappy fuel mileage you can't just assume that you are too rich. Once you start leaning out the mixture past the point where power starts to suffer fuel mileage can go down hill as well since you end up having to open the throttle up more then you should just to go however fast. Basically you can lean it out past the point of efficiency.

I never knew that, I always thought it was running rich, but it makes sense for sure, with the modified exhaust as Tom pointed out it will run lean with the standard ECU

Thinking it too rich I leaned the PCIII map out "to use less gas" and it ran hotter I, I should have been going the other way which is counter intuitive.

I will try it this week if I get a chance.

Thanks

Roy

Update June 24th 2010

OK, I put the PCIII back on and richened up the mixture across the board

After a run of about 6 km I quickly measured the cylinder temperature with one of those point and shoot thermometers pointing at fins just below the plug ~115°C for one cylinder ~120°C for the other, that seems reasonable to me. It wasn't a hot day.

[raz]

Inspecting a spark plug will tell you a lot

[luhbo]

... and it runs very hot in city traffic....

 

That's absolutely normal. You probably don't have a temp. gauge installed, but having an Optimiser installed I have seen that above 25°C (shadow) moving the V11 in urban traffic quite quickly leads to temps above 120°C. This being just a number the feeling for this is not just hot - glowing or cooking hot is more appropriate. Oil temperature then might be not far below that.

 

So you shouldn't screw up the whole bike just because the engine feels hot when used inappropriately and because you have this PC thingy at hand.

 

BTW: an open exhaust makes the AFR some 5% richer at midrange and some 5% leaner at the top end. Nothing the stock map wouldn't cover.

 

BTW 2: a PC is totaly useless if not even counterproductive for addressing running conditions as high engine and high ambient temperatures.

 

Hubert

[Kiwi_Roy]

Inspecting a spark plug will tell you a lot

Yes, I will do that as soon as I can get a reasonable ride in, please see update in previous post - Roy

[Kiwi_Roy]

So you shouldn't screw up the whole bike just because the engine feels hot when used inappropriately and because you have this PC thingy at hand.

Hubert

I take your point, if it an't broke don't fix it!

 

With a somewhat richer mixture it did seem to run cooler, I think I had screwed it up thinking excess fuel consumption = rich mixture.

A short run (~6km) with the mixture lean and it smelt really hot, I didn't measure the temperature but now after the same run it's about 120°C

Roy

[GuzziMoto]

I take your point, if it an't broke don't fix it!

 

With a somewhat richer mixture it did seem to run cooler, I think I had screwed it up thinking excess fuel consumption = rich mixture.

A short run (~6km) with the mixture lean and it smelt really hot, I didn't measure the temperature but now after the same run it's about 120°C

Roy

Yeah, obviously the mixture can make a difference in the temp it runs at. I think part of what he was getting at is with the MyPC thing you can adjust the correction factor that is applied based on engine temp if I heard correctly. The stock set up leans out the mixture at higher temps. With Cliffs MyPC you may be able to richen the mixture back up at higher temps to assist in cooling a hot motor. Or not.

[luhbo]

.... With Cliffs MyPC you may be able to richen the mixture back up at higher temps to assist in cooling a hot motor. Or not.

 

Not.