docc Posted July 9 Posted July 9 Second time this happened to mySport in high heat after a short run up the road (thirty minutes), and a very short stop->restart (minutes) attempt, then failure to run. Like a "vapor lock." First time, it cleared out suddenly after maybe twenty->thirty minutes. Like it never happened. This time, (High heat: 95ºF/ higher "heat index"), I got maybe 200 yards and the Sport would not recover. Tried cycling the fuel pump (a dozen+ times). Opened the tank cap several times. Chatted with several concerned locals stopping to check on my plight. After an hour pinned between the edge of the road and the guard rail, I thought it would restart after "cooling off." Fanned the petcock/fuel line/fuel pump over the left cylinder/head. No joy. Started to fret over the Timing Sensor. The ECU. Swapped in a fresh #5 (fuel/ignition) relay . . . Figured I fouled the plugs with so many restart attempts an decided to swap in new plugs (always carry new plugs!) thinking the bad plugs would be wet soaked from so many restart attempts. After an hour cool down and fresh plugs, started up and rode home . . . Yeah, they are "plugs", just not *spark*-plugs! Right as I was celebrating turning 134,000 miles . . . 5
gstallons Posted July 9 Posted July 9 Sounds like you had a disappointing day . Relay #1 is working because the starting motor works. Relay #2 is working because the headlamp is ( I assume) working ? The way to verify it is working (since you don't wont to lean over the bike) is to push the horn button. Relay #3 is working because the starter is allowed to crank. Relay #4 is working because it supplies +to Relay #5 Relay #5 would give you evidence of working when the fuel pump would (make noise) function . The #5 relay controls the + to the fuel injectors , ign. coils and the fuel pump. 4
docc Posted July 9 Author Posted July 9 On 7/9/2024 at 1:53 AM, gstallons said: Sounds like you had a disappointing day . Relay #1 is working because the starting motor works. Relay #2 is working because the headlamp is ( I assume) working ? The way to verify it is working (since you don't wont to lean over the bike) is to push the horn button. Relay #3 is working because the starter is allowed to crank. Relay #4 is working because it supplies +to Relay #5 Relay #5 would give you evidence of working when the fuel pump would (make noise) function . The #5 relay controls the + to the fuel injectors , ign. coils and the fuel pump. Expand Yeah, the relays "felt" really hot. My #5 OMRON was dated 2017, so I changed it out to eliminate any contribution. The real game changer was the fresh plugs. Not sure why the high heat and the trashy plugs combined to give me the disappointing day . . .
gstallons Posted July 9 Posted July 9 (edited) The rest of the diagnosis is needing to be packing a spark tester. If you had more than three hands you could unscrew a spark plug cap and hold the end of the plug wire near the head while cranking to test for spark. The fuel pump (vapor lock) issue would be up to you to diagnose. You would have to remove a lot of stuff (on the side of the road) to test fuel pressure . Edited July 9 by gstallons more info 1
gstallons Posted July 9 Posted July 9 (edited) AFA spark plugs , I have to keep 4 NGK spark plugs here at the shop all the time . If the bike does not start , I have to put new plugs in. Edited July 9 by gstallons 1
docc Posted July 9 Author Posted July 9 Re-priming the fuel pump sounded "weedy." I thought I could "clear" the lines/pump/injectors by cycling the pump. Never worked out. At 5,000 miles, those plugs look "bad" to me . . . You can imagine my joy, starting the Sport up and riding away, after changing the plugs on that roadside after an hour in the immense heat . . . 4
gstallons Posted July 9 Posted July 9 IDK why these bikes EAT spark plugs . The deposits on the plugs do not look good but there is nothing you can do easily to fix this condition. 1 1
po18guy Posted July 9 Posted July 9 I think crappy coils might be part of it, ancient aircraft style combustion chambers are part of it and a cranky F.I. system is probably part of it. As to plugs, I replaced my OEMs with Iridium plugs. I had to know: Iridium is in the platinum spectrum, and is the most erosion resistant of all known metals. Curiously, it is deposited around the earth's crust in two distinct layers. Meteor strikes are suspected. Yet, it's here for a reason, so on my spark plugs it is. 1
gstallons Posted July 9 Posted July 9 They started plating the center / ground electrodes to prevent wear of the material and increasing the air gap. The better the plating material , the longer the lifespan . It ain't gonna prevent build-up like is on Docc's spark plugs . I am still "sitting on the toilet" musing about what caused the breakdown on the bike yesterday . the fact it was a no start after a hot-soak....hmmmmm. Chemtronics sells Freeze Spray . r-134a in a can that will COOL down any electrical component to diagnose "if" it is the fault. BTW , Docc , these smaller relays will get so hot you are going to think they will melt . Mini and Micro relays are used in everything and I cannot understand why they are put in high current situations. 2
Joe Posted July 9 Posted July 9 Docc, I’m glad you rode it home, just short of a miracle. I have a question, is the heat shield still glued to the bottom of tank? Mine had fallen off early on during ownership of my first 01 V11 Silver Sport. Off memory, that’s fading, it would act the same way riding in extreme South N’ humid heat coughing and dying while slowing down to idle. Cheap low octane or bad gas would make it have episodes too. Like Gene stated, the relay logic of the bike was functioning fine. I remember checking everything on the bike, then it would eventually fire up and be ridden directly home. Last question, how much impact does the heat shield have on extreme heat days, could the fuel be getting too hot? 1
gstallons Posted July 9 Posted July 9 IDK how much the heat shield "material" would affect the temp. difference , I know it would alter the heat transfer..... It would be a good idea to maybe put extra between the tank and engine area just in case .
docc Posted July 9 Author Posted July 9 Thanks for the replies, gentlemen!! @po18guy, It occurred to me that the coils could be "tired" and contributing. @Joe, The tank heat shielding is intact. @gstallons, On the side of the road, I would liked to have had some freeze spray or electronics cleaner to selectively cool components, especially the petcock, fuel line, and pump. They were too hot to touch. 3
p6x Posted July 9 Posted July 9 I am amazed at what you carry with you, in terms of spares. I take nothing because I like to trust my motorcycle. So far, it has not "really" let me down... I am interested in the "vapor lock" discussion, because I used to have a car that you could not leave in the sun for long periods of time, else, it would be really hard to start. This was a 504 Peugeot, with the carburetor right beneath the hood, and no insulation, mechanical fuel pump and long feed lines. From what I understand, vapor lock vanished with injection and electrical fuel pumps. But motorcycles do not have direct injection, so could vapor lock still be present under certain conditions? I did experience a problem that I reported here last year, during an extremely hot ride and several starts and stops to relocate the V11 for best photography. I lost idle and the V11 would immediately die. Docc you told me the temperature sensor may have been the culprit?
docc Posted July 9 Author Posted July 9 On 7/9/2024 at 1:39 PM, p6x said: I am amazed at what you carry with you, in terms of spares. I take nothing because I like to trust my motorcycle. So far, it has not "really" let me down... I am interested in the "vapor lock" discussion, because I used to have a car that you could not leave in the sun for long periods of time, else, it would be really hard to start. This was a 504 Peugeot, with the carburetor right beneath the hood, and no insulation, mechanical fuel pump and long feed lines. From what I understand, vapor lock vanished with injection and electrical fuel pumps. But motorcycles do not have direct injection, so could vapor lock still be present under certain conditions? I did experience a problem that I reported here last year, during an extremely hot ride and several starts and stops to relocate the V11 for best photography. I lost idle and the V11 would immediately die. Docc you told me the temperature sensor may have been the culprit? Expand The fuel supply from our petcock to the external fuel pump (on the early V11) has always been vulnerable to heat soak from the left cylinder/head. Proper grooming away from the heat source and heat shielding the fuel line is well indicated. One of the contributors to this problem in high ambient temperatures/ hot motor is the mapping that runs rich on EVERY startup for about 4000 revolutions regardless of the temperatures. V11 are likely to run very poorly starting when already hot and high ambient temps until past those 4000+ revolutions. @Lucky Phil could recite the exact number . . . 2
activpop Posted July 9 Posted July 9 Super high temps in Oregon this week...no fun also. Oh, to be 55 degrees and cruising again. And 55 years old while we're at it. 1 3
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