b40rt Posted September 3, 2014 Report Share Posted September 3, 2014 I'm at a loss to understand that on a Fi bike Surely you have adjust mixture with a laptop to alter the mapping ? Do you understand the difference between rich and weak ? Whether you use a jet or a laptop to achieveit, its the mixture that's important. 1 Quote Link to comment Share on other sites More sharing options...
billyt Posted September 3, 2014 Author Report Share Posted September 3, 2014 (edited) Br40 with all due respect I don't think you understand the parameters and the non changeable variables we are working with here. We don't need a lesson in carbs or lean vs rich. That knowledge is plentiful on this site. The high altitudes and high heat are what we have to re-act to. The high high altitudes mean less air, the high altitudes and high temps mean not only means less air but the air that is present is VERY hot. Putting a richer jet in to cool it down if at all possible with a lack of air does nothing to help this problem. Re programming the FI system to make it richer can only be done to a certain extent as the quality and quantity of air is still an issue. The programmable ECM engine control management looks at all these variables and controls the fuel deliverable accordingly vie the algorithm. It can add more or less fuel accordingly but it cant control more or less air as this is fixed by the size of the inlet throttle body and the position of the butterfly valve controlled by the throttle tube. If there is not enough air or cool to pull from then we have problem period................. We are trying to figure out how to get more cool air or just more air period into the air box. Going on about jets or jet theory is irrelevant. The ECU will adjust its fuel according to what it sees coming in i.e. concentrating on the mixture as you said. Even if we could change to a richer jet you still need air flow at the correct ratios to make it all work correctly but if there is barely enough air to let the rider breath correctly let alone ask a FI system to work correctly then what? Edited September 3, 2014 by billyt Quote Link to comment Share on other sites More sharing options...
mags Posted September 3, 2014 Report Share Posted September 3, 2014 (edited) I'm no fuel guru but I do know people try to richen the mixture to "cool" and it works to a point but the point where you run out of oxygen to burn it comes quickly (too rich). Richening to "charge cool" is done for knock (detonation) mainly (as far as I'm aware) and to stave it off just that bit longer allowing wider throttle openings. I know one thing.... geez its a complicated science this fuel stuff! All to do with latent heat of the fuel and molecule conversion at the flame front to allow fuel behind into the burn process.... and plenty more techy stuff. Plenty of reading around if you care to make ya brain hurt! (cerebellumWink) Mags Edited September 3, 2014 by mags Quote Link to comment Share on other sites More sharing options...
b40rt Posted September 3, 2014 Report Share Posted September 3, 2014 (edited) [quote name="billyt" post="374858" timestamp="1409585524" I need more air less fuel at the higher elevations, but how? Any suggestions? Your words. Obviously you checked the plug colour, it was black ? Edited September 3, 2014 by b40rt Quote Link to comment Share on other sites More sharing options...
axulsuv Posted September 4, 2014 Report Share Posted September 4, 2014 Billy ; I've been tweeking fuel injection almost since it's inception ... But I'm not familiar with how the 4rt measures air . Does it have a Map sensor and intake air temp. sensor or is there a air flow meter of some type ? But I can tell you one of my riding com-padres has a 05 that has been played with by the HRC guys and has different mapping than stock and the bike is unbelievable !!! with the flip of a switch it will go from a sleepy cub into a fighting Tiger .... And if you can learn where to use each , the bike is phenomenal . other than that it's just a perfectly set up ride I'll see him this weekend at a event and I'll ask him to contact you and share any info he knows ... You may already know this Scottish Gentleman . And I hope when I'm his age I can ride 1/2 as good as he can .... Glenn And my gas caps should be here tomorrow ! Thanks ... Quote Link to comment Share on other sites More sharing options...
billyt Posted September 4, 2014 Author Report Share Posted September 4, 2014 (edited) B40rt If this was a stock venturi carb you would expect to see a blackened sooted plug in the issue I experienced on Sunday. In this case (extreme case of high altitudes, high temps, stagnate air flow) of a FI system you would expect the opposite as in lean and white plug, why? All fuel metering devices be it venturi or FI try to control the ratio of fuel to air. Not air to fuel. In a stock venturi type carb we change jets to adjust fuel flow. The air coming in is set by the rider lifting the slide vie the cable and the size of the carb inlet and outlet and of course the size of the piston creating a vacuum. If the plug read too lean we would richen it up too rich lean it out vie the jetting. On a FI system the sensors read air pressure air temperature and throttle position vie a sensor reading throttle opening this last one basically tells the engine management computer how fast the rider wants to go and how much air is going to be let in vie the throttle position. Once these readings take place the computer tells the injector how much fuel to squirt in to maintain a given fuel to air ratio. For a standard carb and FI system There is a different fuel air ratio for each given RPM or throttle position or in a standard carb a different ratio for each jet or needle position. Outside of re programming I have no control over the amount of fuel I can only control to a certain degree the quality and quantity of air being drawn in. If this is true then as the air drops in quality and quantity then the engine management control will try to respond by cutting back the fuel accordingly to try and compensate for the lack of air, all while trying to maintain the correct fuel air ratio at each given throttle position. There will come a point where at higher RPMs the correct draw for air will not be reached due to altitudes and extremely warm temperatures and stagnate ambient air flow so the FI management system will cut back the fuel accordingly, something has to give, my throttle position sensor is saying to the engine management unit the throttle is wide open therefore lots of air should be coming through yet the sensors that sense the air quality air temps and pressure is saying nope we don't sense that, turn the fuel down, yet the engine is still spinning wanting fuel and creating lots of vacuum pulses and in turn a lean condition at the plug tip hence why my plug is whitish. One would expect to see a leaned out whitened plug in this scenario which I did. The opposite is also true. That at sea level the FI system still tries to control fuel to air ratios. At sea level it will see lots of cool air coming in and will give out more fuel to the injectors as the ratio needs to be richened up as there is more air available. Or in winter time it will sense cold dense air and provide more fuel to keep the ratios constant. Hence why we richen jetting up for winter and/or use a choke. Or maybe I am full of crap and too old to grasp FI Glenn Yes the system has lots of sensors monitoring the air quality, temps, pressure, throttle position, crank position etc. Look for the attached PDF in one of my above posts showing the sensor layout. Tell your Scottish friend I am from Glasgow and live in the USA now. I can give you my cell number if you wish to give it to him. Hope you get and like your V Mar gas caps. Cheers Edited September 4, 2014 by billyt Quote Link to comment Share on other sites More sharing options...
billyt Posted September 4, 2014 Author Report Share Posted September 4, 2014 (edited) Billy, I checked my valve clearances at 2-3 hrs use on my 2014 and they were spot on. I assume they would be need checking again in about 40 hrs? Chatting with importer here in Australia he has not seen them out from factory... highly improbable to be out at this stage but not impossible. The pipe out of the head is a crankcase scavenge/vent system AFAIK. So technically, dirty air (potentially oil misted air) gets drawn back into engine. Should not be an issue normally, as Honda engineers are pretty good! (wink) Can be an issue if rings/valve guides are worn excessively. Mags Mags There are actually two breather tubes/hoses. One from up top (valve cover) and one from the top of the crankcases. The one from the top of the valves runs into a reservoir and then on to the air box. That one has already been removed from the air box and relocated. The other just hangs out pointing downwards. Edited September 4, 2014 by billyt Quote Link to comment Share on other sites More sharing options...
b40rt Posted September 4, 2014 Report Share Posted September 4, 2014 "My plug is whitish" = lean,the rest is just a bit patronising. Quote Link to comment Share on other sites More sharing options...
billyt Posted September 4, 2014 Author Report Share Posted September 4, 2014 (edited) Or necessary to stop ye bleathering on aboot brass jets. Auld reekie nippin year heid. So what jet do you want me to change to fix the problem. Or any suggestions in how to re-program the FI to get more fuel even when there is very little air? The baw is in yer court. Teach us all about FI. Edited September 4, 2014 by billyt Quote Link to comment Share on other sites More sharing options...
b40rt Posted September 4, 2014 Report Share Posted September 4, 2014 Parameters - you can't change the elevation, temperature, humidity or wind. You can "fiddle" with the air box. So that leaves .............. Quote Link to comment Share on other sites More sharing options...
billyt Posted September 4, 2014 Author Report Share Posted September 4, 2014 “So that leaves” What....... Yer a*** hinging out the windea or what. “You can fiddle with the air box” Eureka......... As stated all along I need more air flow/volume just as others have also stated by their air filter/ flame cage removal, air box/ crank case hose re routing, open up the fender air breather holes, recommendations. You started off by suggesting to change to a richer jet and then got all pissy when it got ignored. In this FI case more air at or passing by the air sensors equals more fuel being injected in equaling a correct air fuel ratio and hopefully a better running bike. Still open to any others suggestions or experiences at high altitudes, high temps, little to no ambient air flow in wooded conditions with the FI Repsol. Quote Link to comment Share on other sites More sharing options...
b40rt Posted September 4, 2014 Report Share Posted September 4, 2014 (edited) This leaves fuel. Fiddle with the air box = bullyt with his Wal-Mart battery drill trying to make his air box a collander. Edited September 4, 2014 by b40rt Quote Link to comment Share on other sites More sharing options...
jrsunt Posted September 4, 2014 Report Share Posted September 4, 2014 On the subject of drilling the airbox, To try solve the air issue I cut away the plastic top that sits on top of the filter, leaving only the rim and 4 bolt holes to secure the filter. This worked a little at altitude but completely ruined the running at normal altitudes. It may be worth a try, but get yourself a new filter top before hand. No need for a battery drill, a hack saw blade does just fine. Quote Link to comment Share on other sites More sharing options...
guys Posted September 4, 2014 Report Share Posted September 4, 2014 (edited) On the subject of drilling the airbox, To try solve the air issue I cut away the plastic top that sits on top of the filter, leaving only the rim and 4 bolt holes to secure the filter. This worked a little at altitude but completely ruined the running at normal altitudes. It may be worth a try, but get yourself a new filter top before hand. No need for a battery drill, a hack saw blade does just fine. Doesn't the race kit have such an "open airbox cover"? Mine does anyway. The throttle body has 3 sensors: Intake air temperature sensor, Throttle position sensor and manifold vacuum sensor. If you like something to read, this explains the Honda PGM-FI (electronic fuel injection) system for small motorcycles : http://montesa4rt.nl/data/information_honda-pgmfi.pdf I know this guy made the inside diameter of the throttle body lager but I think it was only done to gain power, not to adjust for hot dry air at high altitudes, considering he lives in Holland Lot's of tuning stuff on his site: http://montesa4rt.nl/ I suppose you've thought of this also: In order to activate the competion mapping there must be made a small modification to the wire-harness if the lights stay on the bike. If the lighting is removed which is mostly the case, the electrical restriction will be automatically removed. Edited September 4, 2014 by guys Quote Link to comment Share on other sites More sharing options...
mags Posted September 4, 2014 Report Share Posted September 4, 2014 Still open to any others suggestions or experiences at high altitudes, high temps, little to no ambient air flow in wooded conditions with the FI Repsol. Supercharger to get some air density back, intercooler to lower intake charge temp (adiabaticWink) First drag-racing trials bike! Hehehehe 2 Quote Link to comment Share on other sites More sharing options...
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