High Air Temps and Engine Ping?

[Tom H]

My EV in air temps over about 95 deg F has a tendency to ping under quick acceleration, as in starting to pass a car while in 5th and 3000-3300 RPM (about 65 mph). I normally cruise at 3500 rpm at about 75 indicated/73 acctual mph. The other day I was stuck in stopped traffic that I filtered though in 1st, but the bike was hot and pinged in 3rd and  4th until I got some air to it. It was hot, all the cars you could smell the coolant.

In normal air temps, the bike is fine, but we are in a heat wave again.

I run premium gas, stock '04 EVT map, good plugs and the CO was at +10.

I have changed to CO to +20 to see if this will help today.

Any thoughts on what else I can look at to get rid of the ping? The old bikes I'd check the timing and points, can't do that on the EV.

Thank you,
Tom

[Don G]

Maybe don't lug it! DonG

[Wayne Orwig]

Downshift. Get the revs up.
I too enjoy my 2004 EV motor when cruising along around 3500. But I would downshift under those conditions to accelerate.
Or look for more octane when it is hot. Maybe octane booster in hot weather.
Move to a colder climate.
Change the timing. Guzzidiag can do that with some work.
Lower the compression.
Still sounds like 'downshift' is a good answer.

[beetle]

Throttle body balance. This can cause pinging if not correct. Otherwise, you could also tweak the air temp and/or engine temp correction tables in the map.

[Tom H]

Just balanced the TB's the other day at idle and 3500rpm when I changed a intake boot. BTW: had the same problem before the change.

I guess I'll downshift in hot weather to pass. I'm just concerned about this if I was climbing a hill like between Yuma and San Diego in the warmer months. Need to visit Yuma again one of these days.

Thanks all so far.

BTW: the hydro does cruise nice at 3500rpm!!

Tom

[Two Checks]

Whacking the throttle at 3-3500 rpm in 5th is asking it to ping.
Drop 2 gears.

[rocker59]

two quick ideas:  more RPM.  higher octane gas.

5th gear and 3000 rpm is just asking for ping with a full throttle roll-on.  You're in "lugging it" territory there.

[Tom H]

FYI, when I do make a pass, it's more of a roll on to about 1/2 throttle (never measured where my cruise throttle "1/4"? is or my passing throttle "1/2 ?"). Not a sport bike race around.

In cooler weather and under the same passing conditions, no problems. From about 60-65mph to 75-80 quicker than I want 

But I'm sure your all correct, I should drop to 4th, it just sounds so over reved to me, though I know it still has plenty of revs to go.

Tom

[oldbike54]

 Tom , just for my own information , this is a Hydro with the recall done properly ? They tend to be more flexible than solid lifter versions . I might do an exhaust gas measurement , or at least do a plug chop test from a steady 3500 RPM's . Might give you a clue as to what is actually happening . Any chance one of the hydraulic lifters isn't pumping up ?

 Dusty

[Tom H]

Yes, the updates were done as far as I can tell without pulling the cam, the rockers were done. The cam looks fine from below.

As for the lifters, I did check them by a push down by hand that was described here. All were fine as far as I can tell.

I do have a rattle somewhere only when the bike is hot at idle, above 1500rpm the noise is all but gone, it's not the standard clutch rattle. It runs fine at idle and cruise, well except while passing in hot weather.

For the noise, I still need to pull the front cover to check the chain, can't believe that the chain could be bad with less than 20K miles. The noise sounds like something rotating, think of the old lug nut in the hub cap joke sound where it rattles then stops, then rattles again, then stops. It rattle in a rythem, like 3 rattles then silence for about the same duration, then starts again. Way too slow for crank speed, and I think too slow for cam speed as well?? Once I get some family matters sorted, then I'll be pulling the cover.

Thanks again,
Tom

[Wayne Orwig]

BTW: the hydro does cruise nice at 3500rpm!!

Yes it does. I seldom encounter pinging at the slightly higher elevation where I am. If I know I am heading to the coast during hot weather I do look for the high octane stuff as I have encountered it then. I

[Tom H]

Well....With cooler temps this evening, no ping. Tried hard to make it happen. Might be on a day freeway ride tomorrow. Will let you know if it still pings.

With the CO +20 or the lower air temp, all seems well. Will check gas mileage to see how much that has changed with the CO change.

Thanks again for the thoughts!!!!!!!
Tom

[Huzo]

EXACTLY, the same symptoms as my Norge used to have and you have described it as if you were on MY bike. I had it remedied by a reputable Guzzi officianado but the fuel usage is not really acceptable. I have an amateurish mechanic who operates in Bungendore (Australia), not far from where I live,  who is going to Beetle it and anything else it needs. I expect that will bring the economy back to decency without incurring the dreaded "ping". Mine would do it exactly as you say in Temp's above 33deg C and RPM below 3,500 and as little as 50% throttle. People always say you must be lugging it, but at it's worst you had to be extremely careful and that's not acceptable. Interesting to read the comments regarding throttle body balance.

[Wayne Orwig]

Well....With cooler temps this evening, no ping. Tried hard to make it happen. Might be on a day freeway ride tomorrow. Will let you know if it still pings.

With the CO +20 or the lower air temp, all seems well. Will check gas mileage to see how much that has changed with the CO change.

Thanks again for the thoughts!!!!!!!
Tom

Have you connected it to diagnostics and verified that all of the temp sensors and air sensor are working? And that the engine temp sensor is roughly working as the engine warms up? That bike has a temp sensor mounted it crappy plastic which can break.

[Tom H]

I have GuzziDiag and the air and engine temps are being read by GD. If the temps are right or not, I don't know. It does have the plastic engine temps sensor holder. The engine temp does change on GD while the bike warms up and cools down.

I'm not sure that I remember the engine temp right, but after about 10 minutes with the engine off then hooking up GD, I think the engine was at 83C and the air was at 33C. I could be wrong on the temps.
The weather said the air temp for my area was about 90F at that time.

For fuel mileage, before the CO change was 40-42 mpg for my 3 day 120 mile route to work of mainly freeway with just a short section of 40 mph zone. I would use between 2.8-3.0 gallons for the trip.

Thanks again,
Tom

[Tom H]

Two more things on this.

Oil pressure: There was a thread that RK asked what oil pressure people were getting. My pressures at various RPM were normal. My normal low is 10-15psi at idle when I get home, that day it was about 5psi. This is measured with a cheap fleabay electronic gauge. Did I mention it was HOT out that day??

Maybe I have a fueling issue with the stock map? The bike runs smooth at 3500rpm at about 75mph. One I get to 80mph and 3700-3800rpm it gets a vibration. It starts at about 3600 and increases as I get to 4000. Over 4000 it seems to smooth out a bit. Don't know for sure, don't like to go that fast, that's about 90mph.

Tom

[LowRyter]

richen it up.  Revving works unless you're in town and parading around, then it just gets hotter, retard the timing, get octane booster.   But keep the RPMs up over 3500 and never lug it.

my '98 EV has a trim tab on the computer to richen the whole mess. 

it's all richen the mixture, timing and octane.  I don't know what you can do with those three things.

[Tom H]

It was fairly hot again today. Didn't hit the freeway, but about 20 miles of street.

With the engine very hot from the traffic. Normal shifting it did not ping. I was able to get a single ping when I started at a light in first, then shifted to third and about half throttle, then it pulled nicely. On a fairly steep hill, I was able to get it to ping a bit. I normally go up the hill in second, this time in third and it pinged a few pings then cleared and pulled nicely.

LR, I did richen it up a bit when I changed the CO from +10 to +20 with GD. If I remember right, it does the same thing as your screw on a believe a P8 ECU. I'm just knot sure it if affects the entire throttle/rpm range or just a certain section of throttle/rpm range.

More testing to follow.....

Thanks again!!
Tom