| Author |
Message |
    
Blake
| | Posted on Tuesday, August 29, 2006 - 08:48 pm: | 
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Doc Greg,
I'm not sure on the lifter guides tolerancing, just guessing out loud. More significant may be the backdriving of the cam gears. |
44mag2
| | Posted on Wednesday, August 30, 2006 - 12:46 pm: |
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Davo,
I agree with you ... moving the curve is the easy/cheap solution. If Buell does not fix the problem, I will likely move the curve with the static timing. It's just that I want the timing curves in the ECM to be correct ... no reason for them not to be. Other bikes get it right, no reason why Buell can't. |
Husky
| | Posted on Wednesday, August 30, 2006 - 10:17 pm: |
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I would like to share this Harley/Buell Fuel Injection article with you. If you haven't seen it or the info. before it might help with our understanding of the Pinging (pre-ignition ) problem and how to go about solving it.
It has a few additional links in it that are also important.
http://www.nightrider.com/biketech/motorcycle_efi_basics.htm#null |
Davo
| | Posted on Thursday, August 31, 2006 - 12:08 am: |
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44mag2,
Have you heard anything from the factory other than to bring the bike back in to the dealer? |
Opto
| | Posted on Thursday, August 31, 2006 - 07:09 am: |
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I believe the ignition curve isn't optimal but I'm no engineer, just a rider/Buell customer. The pinging seems to stop around 4200 rpm on my 04 XB12, when the bike is in ping mode which is when the fuel isn't up to scratch. I even got a ping or 2 in winter out of the blue, surprised me. I find that it's not fuel (I run alternate fuel system with WB AFR readout) so it *nearly* has to be the ignition curve. I would think they run a 2-D ignition map, so if you open the throttle at a certain steady rpm, the timing retards to reflect the load. I know that anyone with the Direct Link software could tell us what the ignition map consists of but I don't expect anyone to let it out, so that we can further understand our Buells. As it is there's heaps of ignition maps around on the net known to work fairly well with modified Sportster motors developing similar power. It's confusing as the circumstances on my bike if repeated don't always produce the same result. I really don't know what the answer is and I do fully trust the Buell engineers, but something seems wrong on just a few bikes at least. Terry from the exhaust shootout said he was working on some timing changes but I haven't followed the BWB much to see what resulted. I am working right now on alternative ignition (programmable) to see what happens, it will take a while, would be real nice to take the edge off the timing advance in the midrange under load. |
Merlyn
| | Posted on Thursday, August 31, 2006 - 07:36 am: |
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Quick question:
With Blake's engine-heated air temp sensor scenario in mind, is anyone running Odie's airbox heat sheild having pinging issues?
If the ATS being heated by the engine is part or even the root of the pinging problem, and the sensor is mounted in the airbox, then isolating the airbox from engine heat should reduce/eliminate the pinging, no?
Merlyn
--Too short for a Uly! |
Lorazepam
| | Posted on Thursday, August 31, 2006 - 09:09 am: |
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I have aluminum tape under the seat, and my bike doesnt ping. It hever has, even when the fan died.
If 3 degrees of timing is 1mm, what is the chance that the pinging bikes have a bad cps? could have been dropped, or there was a run of bad ones? |
Snowscum
| | Posted on Thursday, August 31, 2006 - 11:31 am: |
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CPS=???? |
Treadmarks
| | Posted on Thursday, August 31, 2006 - 03:28 pm: |
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CPS= Crank Position Sensor |
Blake
| | Posted on Thursday, August 31, 2006 - 04:04 pm: |
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Some folks here seem to be assuming that their pinging is indicative of a fleet-wide systematic problem. I don't see that as a valid conclusion. I may have contributed to that sense through wild guess ideas posted here above. Sorry for that.
Other possibilities? It may well be that some sensors are simply out of spec. When you purchase lots of 10,000 temperature sensors to normal commercial quality specifications, there will be some that fall outside of the required performance specifications. That is just one other of many possibilities in this situation.
We have an O2 sensor, and IAT sensor, a TPS, a cylinder head temperature sensor, two electronically operated fuel injectors, analog to digital voltages, an ECM, a TPS zero calibration, a cam position sensor, cam position sensor setting (static timing setting) any one of which if operating out of specified range can contribute to a leaner running engine that then has an increased risk of detonation.
I was once hired to help rescue a multi-million dollar military satellite communications program/contract from termination by the pentagon. It was on the pentagon's urgent problem hit list and without a major turn-around in quality, it was heading for termination. The situation was dire. The program was also horribly behind schedule. Great combination that.
Anyway, after much investigation gnashing of teeth, pulling of hair, learning more than I ever imagined about frequency converters, oscilators, power supplies, and the like, it turned out that there were a multitude of root causes for the various problems/failures.
Some were due to misuse by the customer exposing the equipment to moisture/condensation; some were due to marginal engineering; some were due to inadequate protection against static electrical discharge during manufacturing; some were due to improper assembly methods; some were due to poor quality assurance practice, and some were due to components not performing as required.
In order to address the out of spec component problems, we had to increase the quality assurance inspections of those components to 100% while we worked with the vendor to improve their quality, while begging them to ship the next lot on schedule. What a NIGHTMARE! We also increased the rigor of our quality assurance testing for the completed equipment.
But even after all that, even after totally transforming the manufacturing and quality assurance not only of our facility, but also those of our major subcontractors, after recalling and reconfiguring (engineering upgrade) all the equipment, we still saw failures, not anywhere near as many, but too many to suit me. I was and remain to this day very suspicious that we had a saboteur in-house. I hope they caught the scoundrel.
Sorry, just blathering. |
44mag2
| | Posted on Thursday, August 31, 2006 - 07:50 pm: |
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"Have you heard anything from the factory other than to bring the bike back in to the dealer?"
They won't talk to me in person, as they prefer to communicate through the dealer. However, my dealer did say that the factory is concerned about higher than average amounts of ethanol in fuel across the country ... as much as 30%. Now this is second hand information, nevertheless, it is what I was told. |
Snowscum
| | Posted on Thursday, August 31, 2006 - 08:53 pm: |
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If that was the case then there would be more
people complaining about pinging.(ethanol)
Blake I am in the aerospace industry.
I can relate to your blathering.
I work for one of the major subs and its
a tough biz to be in. Between funding issues
and slow times. It's hard sometimes to get a good product to launch. |
Diablobrian
| | Posted on Friday, September 01, 2006 - 01:28 am: |
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Error "stacking" sucks. Been there done that as a prototype machinist trying to explain to an engineer why his specs had
tolerances that were too loose. They get funny looks on their faces when you tell them the opposite of what they expect to
hear 
I think a little more intensive dealer set-up would probably solve the problem. However many dealers don't even go over the suspension
set up with the customer, will they pay more attention to a detail that most people will never see or even know about?
The cynic in me says no.
The hardest problems to solve are usually when you get bad parts new out of the box. This is true of any machine.
Rambling on and on and on... |
Davo
| | Posted on Friday, September 01, 2006 - 01:37 am: |
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Possible good news for tuners. TR's VDSTS has a 2.81B version available for download. Maybe the AFV is active! Been wrenching and timing old school stuff all day today and most of the night. I will break out the lap top tomorrow and see if the AFV is working. The last update had a AFV channel but the value was always 100. I am looking forward being able to see if the AFV is happy with the mixture feedback. If it pings we will now know why!!! We will be able to compare AFV values of pingers with none pingers. |
Blake
| | Posted on Friday, September 01, 2006 - 02:05 am: |
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Davo,
If the value sticks at 100, try resetting the screen to another report config, one other than AFV, then back to AFV again. |
Opto
| | Posted on Friday, September 01, 2006 - 04:03 am: |
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Blake,
You have a good point about the AIT sensor getting heatsoaked - it does, but the ecm must have software to compensate for this, otherwise the Buells would run really bad after being shut down and parked in the sun for half an hour, when an ambient temp of say 23 C becomes 45+ C in the airbox (derived from direct measurement of the voltage at the sensor). After about 5 mins riding the AIT will settle at about 30 to 32 C, it always runs higher than ambient when the bike is warmed up. Maybe this is how Buell gets a small amount of warmup enrichment when the motor is cold? With my alternate fuel setup I had to put another temp sensor under the instrument cluster where the measured ambient temp is more stable. The Buell ecm seems to be configured to run very well with the sensors it uses. I wish I had answers but I don't think the pinging is directly due to the amount of fuel the engine is getting.
Ian.
(Message edited by opto on September 01, 2006) |
Davo
| | Posted on Friday, September 01, 2006 - 07:24 am: |
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Opto,
Does your bike ping under certain conditions? What grade of fuel is available to you? Does it have ethanol and if so what percentage?
Also, didn't you have a contact in Germany with some really good data regarding the CPS operation? |
Davo
| | Posted on Friday, September 01, 2006 - 07:30 am: |
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Blake,
Have you been able to read the AFV? |
Opto
| | Posted on Friday, September 01, 2006 - 06:13 pm: |
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Davo,
Fuel quality is the key issue for me, with the best fuel there is no ping, but it can only be found in the cities, but I don't ride much in cities. I only tried an ethanol blend once and the AFR went leaner. When I do get ping with lesser quality fuel it is only below approx 4200 rpm, suggesting to me that if the advance curve could be made a bit less aggressive I could probably run these fuels. Some of these lesser quality fuels run fine, but some don't so it's a 50/50 chance what is going to happen - that's the bit I don't like. Maybe it's time to put the Uly on the dyno and keep retarding advance until HP drops, see how far I can retard without power loss. I have a Uly and an 04 XB12 and the characteristics regarding pinging are identical.
The data from the German dude was from another site, I don't know him. |
Snowscum
| | Posted on Friday, September 01, 2006 - 07:27 pm: |
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I've personally tried every vendor of fuel in the boulder/denver area and it doesnt seem to matter. It pings a little less with Sinclair
that is refined in Wyoming. I only know of
one station in a 50 mile radius so it is a problem. |
Davo
| | Posted on Friday, September 01, 2006 - 08:40 pm: |
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Opto,
If you have been following the ping issue you know that my timing is about 7 degrees late. The fuel pump cycles just as the TDC mark leaves the window. I am getting 55mpg and my plugs look good. Are you using TR's VDSTS to read the AFV? |
Al_lighton
| | Posted on Friday, September 01, 2006 - 08:52 pm: |
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Earlier versions of VDSTS did not correctly read AFV (and all of them incorrectly label it Air Fuel Value). The current version does read the AFV.
HOWEVER, any time the AFV has been reset, you MUST power recycle the ECM to get the right reading. It will stay stuck at the previous value until the bike has been recycled or the bike has been driven and it re-learns.
Al |
Davo
| | Posted on Friday, September 01, 2006 - 09:09 pm: |
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Great news, version 2.81B of TR's VDSTS PRO USA has an operational AVF! Better than that my readings with a static retard setting of 7-9 degrees is hovering at 100. 101.9 is as high as it has gone. At times of throttling up the value drops to 93! The 101.9 suggests that there is no intake manifold leak and the 93 suggests that my retarding the timing has richened up the O2 and therefor the combustion chambers are as the plugs indicated cooler and richer and that is why I now have no more pinging. The experts seem to have been wrong on this one, retarding the timing does not adversely effect the fuel curve in such a way that it would damage the engine. |
44mag2
| | Posted on Friday, September 01, 2006 - 11:12 pm: |
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Davo,
Please explain the exact meaning of AVF, and what is a good value.
Also, it is my understanding that an overly-retarded timing will overheat the exhaust valves and cause valve damage. This is because the valve is still open when the mixture is ignited, so some of the flame vents out the exhaust valve.
However, I agree, it sure seems like the data supports your timing fix. It would be interesting to measure the EGT (exhaust gas temp) with and without the timing change. I will do that if Buell does not fix my ping. |
Davo
| | Posted on Friday, September 01, 2006 - 11:30 pm: |
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44mag2,
There is a good description of the (adaptive fuel value) AFV in this post:
http://www.sporttwin.com/Forums/viewtopic/t=1553.html
Basically I am using the AFV as a window as to how the engine is learning during closed loop so the ECM can have a bench mark or point of reference for where the air to fuel ratio needs to be when the engine goes to open loop. 100 is the sweet spot and the reset value. Any number over 100 is a reaction to a lean condition and numbers less than 100 are a reaction to rich condition. AFV's are relative to 14.7 to 1. If you are leaner that 14.7 to 1 and if your fuel has any significant ethanol mixture in it then your going to ping. I would like the people with VDSTS to post AFV numbers when referring to ignition problems or perfections. |
Davo
| | Posted on Saturday, September 02, 2006 - 12:00 am: |
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44mag2,
As for the question regarding late timing and its effect on the exhaust valve, I will use a Sportster cam that I believe to be somewhat similar to the Buell cams.
Intake open 28 BTDC
Intake closed 48 ABDC
Intake duration 256 (28+180+48)
Exhaust open 52 BBDC
Exhaust closed 24 ATDC
Exhaust duration 256 (52+180+24)
If the exhaust opens at 52 BBDC that is 128 degrees after TDC of the Power stroke (when the plug fires)
If the stock timing is firing around 7-9 degrees BTDC of advance at idle, which is the actual dynamic reading on a stock set up, then retarding the timing to be 0-2 degrees BTDC gives the fuel mixture at least 130 degrees of crankshaft rotation to harness the energy of the combustion in the power stroke before the exhaust valve opens. The fire should long be out when the exhaust opens. It will however move more heat towards the exhaust side of the head. This should not be a problem. Many cars and even some motorcycles pump fresh air in the combustion chamber behind the exhaust valve to clean up combustion. If this doesn't toast a valve then late ignition timing will not come close to matching the temperatures of fresh air pumped into the mix! That is like leaving the door to the wood stove cracked open.
Note: The specs above are from aftermarket XL cams and are not Buell cam specs! |
Opto
| | Posted on Saturday, September 02, 2006 - 11:06 am: |
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Opto, If you have been following the ping issue you know that my timing is about 7 degrees late. The fuel pump cycles just as the TDC mark leaves the window. I am getting 55mpg and my plugs look good. Are you using TR's VDSTS to read the AFV?
I followed it a bit but not fully. I did a similar thing with a Sportster I used to own, just kept retarding it bit by bit until no ping with average fuel in summer. Each afternoon coming home from work I would nail it on the same stretch of road, and retard it a tiny bit more if it pinged or even hinted at it. I could from then on run any fuel I wanted and I couldn't detect any seat of pants loss of power. That bike is still running the same timing and still goes strong - I sold it to a mate who lives in the bush, he's a mechanic by trade and I've never heard him utter the word "ping" but he does love how nice it runs 
Regards the ethanol, the AFR went leaner, not the AFV, I have a wideband sensor on board and run a Megasquirt FI in continuous open-loop mode, no corrections from the wideband (or stock narrowband O2). The Megasquirt can run closed-loop to AFR target tables but I'm not using that.
Regarding the AFV, I think that 100 is simply the default value for a stock bike. If you run a race filter or different pipe it's unlikely to end up at 100, it will be more than that. Just some food for thought, I was running the MS (Megasquirt) controlling the fuel but the ecm was doing everything else and still connected to the stock O2 sensor. Because I ran the bike a bit richer than what the ecm would like, the ecm steadily leaned itself out to the point where it would no longer run the bike if I switched the ecm over to control the fuel. 6 months later I eventually borrowed a VDSTS and reset the AFV (nice to have a stock ecm as backup). The bike ran but was a bit leaner than it should be, but after a couple rides the stock ecm was back to business as normal. The only mod on that bike is an original Drummer. So 100 AFV is too lean for that setup, but the ecm quickly relearns. I had that bike (04 XB12S) on the dyno recently and the stock ecm was giving around 13:1 to 12.5:1 AFR from about 3k rpm to max at WOT.
I think you're on the money Davo, it's the ignition not the fuel. Considering that in very simple terms higher octane fuel burns at a steady controlled rate in harsher hotter conditions - gee whiz I'm going to get into a lot of trouble here - whereas lower octane fuel can't and is more prone to make an engine ping, then if the ignition timing is retarded a bit (less harsh conditions) then the lower octane fuel is less likely to ping and still do a controlled burn. Hope I haven't opened a techno-debate on burn rates or some other can of worms with this. |
Davo
| | Posted on Saturday, September 02, 2006 - 05:57 pm: |
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Opto,
Thanks for the info. My error, I assumed that you were referring to AVF. I understand now. I have an open loop delphi system on my twin cam that can be tuned with AFR. I spent the last two days in a shop with a bunch of closed course race bikes that were perking off some high octane fuel while they were just sitting on the rack. I really like my clean burning Uly and I would like to keep it clean but I will not put up with pinging. I think another good fix is to go with some longer duration cams to get some more valve overlap which will produce a constant pseudo EGR at low and moderate rpm. |
Opto
| | Posted on Sunday, September 03, 2006 - 01:15 am: |
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Yes, well me and Jim are doing our best to get Megasquirt to control ignition as well, which will give complete control over the spark curve with a 12 x 12 ignition map. I have been beating my head against a brick wall for over 2 and a half years with the pinging issue, so sorry if I come over a bit strong. We'll be giving the Megasquirt option our best shot. |
Blake
| | Posted on Sunday, September 03, 2006 - 01:49 am: |
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Davo,
Yes on Skully's XB9S with his laptop. |
Davo
| | Posted on Tuesday, September 12, 2006 - 11:04 pm: |
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I am eager to hear about 44mag's feed back from the factory. I didn't want this thread to archive until he gets his bike back. |
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