guzziart Posted June 3, 2020 Author Posted June 3, 2020 Hi Docc, OK, for some reason I missed the fact that there was a 3.6º/540mV at idle spec....I can shoot for that. My idle rpm was based on guzzidiag. Thanks, Art 1
docc Posted June 3, 2020 Posted June 3, 2020 IMO, the 0.006/0.008 valve spec is far more important than the idle, as long as the idle is not too low. I do like mine a bit on the high side. I would have to read back through, but where are your air bypass screws set? Also, you asked about increasing the CO. Sure, easy to try, but best to chase down all the other issues first.
guzziart Posted June 3, 2020 Author Posted June 3, 2020 3 hours ago, docc said: IMO, the 0.006/0.008 valve spec is far more important than the idle, as long as the idle is not too low. I do like mine a bit on the high side. I would have to read back through, but where are your air bypass screws set? Also, you asked about increasing the CO. Sure, easy to try, but best to chase down all the other issues first. Hi Docc, I initially set the air screws 1 turn out but tweaked one or the other to balance at idle, adjusted the LH TB grub screw to obtain 1100 rpm or so idle, both TB sync'd at 3K rpm. I've got a shop manual but the info I found so far for idle rpm was 1100 + 50. I'll adjust to the 3.6º/540mV spec and set idle rpm at 1200. And, I'll leave the CO at zero. What are your thoughts on the 6/8 valve spec? Thank you, Art
docc Posted June 4, 2020 Posted June 4, 2020 21 minutes ago, guzziart said: Hi Docc, I initially set the air screws 1 turn out but tweaked one or the other to balance at idle, adjusted the LH TB grub screw to obtain 1100 rpm or so idle, both TB sync'd at 3K rpm. I've got a shop manual but the info I found so far for idle rpm was 1100 + 50. I'll adjust to the 3.6º/540mV spec and set idle rpm at 1200. And, I'll leave the CO at zero. What are your thoughts on the 6/8 valve spec? Thank you, Art All very welldone, Sir! Re: the 6/8 valves: a resounding "yes", IMO. Pretty sure this is referred to as the "World Setting." (0.006"/0.008" = 0,15mm/0,20mm) FWIW, if the air screws have to be set very much differently (>1/4 turn), there is likely a subtle air leak to track down. The rubber intakes are rarely the trouble even though they develop visible cracking.
docc Posted June 4, 2020 Posted June 4, 2020 BTW, the idle setting is in the early V11 Workshop Manual as "Carburation Procedure," Section I - page 52: "Adjust the throttle bodies using the adjustment screw until bringing the idle speed opening to 3,2º-3,6º;" A rather long time ago, someone derived a conversion table to mV: 490mV- 532mV is what is in my notes. Easy enough to confirm this now with a breakout harness, quality DVOM and guzzidiag. I understand using the mechanical synch method and preset idle "target" mV/ degrees of opening. But if your bike starts and runs, the idle spec is the least worry. Get everything else right and put it where it is happy for the riding condition (within reason and range). Please realize the "450 mV" posting was discovered as a transposition and should have been "540 mV." Even this is not an exact spec, but a starting point, or target value.
gstallons Posted June 5, 2020 Posted June 5, 2020 As far as the valve clearance setting , I would set them at a loose 0.006 & a loose 0.008 .
LowRyter Posted June 5, 2020 Posted June 5, 2020 On 6/2/2020 at 2:39 PM, LowRyter said: You know I was using the other specs, 004 and 006. Today I am putting plugs in my Corvette. The plugs were pregapped to .040 and my feeler gauges couldn't enter the gap, not even .035. I had a sparkplug gap tool and sure enough .040 measured on it. If the rest of my feeler gauge is as bad as that, I might be gapping .006/.008. Heck maybe .010+ ? Well just another story how I am dangerous with tools. I decided I'd spend $4 whole dollars and purchase a new set of feeler gauges at HF. So I got the old gauge out to actually compare it to the new one, when I realized that old gauge was fine, but another feeler was stuck on the bottom of the one I was using. So rather than measure .020 + .019, I was adding another .018. Man it was really stuck. Probably should shoot some WD40 in 'em. So now I wasted $4 (Guzzi content). I should've kept my receipt. Just glad I didn't bugger $75 worth of spark plugs (iridium). 1 1
gstallons Posted June 6, 2020 Posted June 6, 2020 If they still sell them , Snap-On sells a spark plug gapping plier that is PERFECT for gapping plugs . I don't remember the part # . I will check when the sun comes up and post it . You don't want to squeeze too hard or you can push the center electrode outta sight !
guzziart Posted June 6, 2020 Author Posted June 6, 2020 On 6/3/2020 at 8:24 PM, docc said: BTW, the idle setting is in the early V11 Workshop Manual as "Carburation Procedure," Section I - page 52: "Adjust the throttle bodies using the adjustment screw until bringing the idle speed opening to 3,2º-3,6º;" A rather long time ago, someone derived a conversion table to mV: 490mV- 532mV is what is in my notes. Easy enough to confirm this now with a breakout harness, quality DVOM and guzzidiag. I understand using the mechanical synch method and preset idle "target" mV/ degrees of opening. But if your bike starts and runs, the idle spec is the least worry. Get everything else right and put it where it is happy for the riding condition (within reason and range). Please realize the "450 mV" posting was discovered as a transposition and should have been "540 mV." Even this is not an exact spec, but a starting point, or target value. Hi Docc, OK, I adjusted LH TB grub screw to get in the middle of the spec...I think the actual was 3.4/530mv. I then adjusted air screws in to around 1200-1250 rpm. I didn't shoot for a specific rpm but where I did leave them gave me the smothest idle. It still will not start without a little twist grip action when cold but I do not think I care at this point, it still runs great. After the adjustments, I began to play with the CO but I didn't realize any difference in the idle so left it at zero. Thanks again, Art 1
docc Posted June 6, 2020 Posted June 6, 2020 Sounds like good results and your V11 made better with every step. Still recalling a range based upon 3.6º, went back to the Workshop Manual and see that the 3.2-3.6º (4.90mV-5.32mV) "using the adjustment screw" (without the throttle rod) in the "Carburation Procedure" Section I, Page 52. The next step, Page 54, "Rules for Carburation, Regulation and Adjustment" then instructs to use the throttle rod to achieve 3.6º+/-0.5º (5.10mV-5.38mV). Seems a convoluted procedure, but we have derived several refinements to the early Workshop Procedure through "Beta testing." Of note, is that opening the throttle plates to get idle speed is more important than CO and the air screws. If you had to open your air screws more than a full turn to get your target idle, opening the throttle plates to 3.6º my make her even happier. Welldone, man! Thanks for posting and showing such perseverance!
guzziart Posted June 8, 2020 Author Posted June 8, 2020 Hi Docc, Thanks and thanks for the help & advice! Of note, is that opening the throttle plates to get idle speed is more important than CO and the air screws. If you had to open your air screws more than a full turn to get your target idle, opening the throttle plates to 3.6º my make her even happier. Funny thing here was that I got the smoothest idle at 3.4 (tried 3.1 through 3.7)and the air screws are for sure less than one turn out. I started at one turn out and turned them in to get idle down to 1200 or so and balance at the same time. Yeah, this whole thing has been a big learning exeperience for me since I've never used Guzzidiag prior to last month! Anyway, thanks again, I'm happy and now can enjoy the bike! Art 3
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