Alpinestarhero Posted June 4 Report Share Posted June 4 Right, I have a question, and I hope it's not stupid, but if it is please forgive my ignorance. I have this irritating issue with my FZ1 that from a closed throttle to getting back on, it feels like a big shunt - that "snatchy" throttle feeling. Most of the time I can be delicate and mitigate it with my right hand, but sometimes (for example, quickly getting back on the throttle in traffic to make the most of a gap opportunity), the bike can "snatch" quite hard, and smetimes thre is this very small but perceptable delay waiting for the engine to reposnd. Now, my question(s) is / are: is this something to do with the PAIR system (which, as I understand, bleeds air into the exhaust for purposes of tidying up hydrocarbon emissions) can i simply blank off the PAIR system to afford an improvement I know getting an ECU reflash would be the best thing, but my money at the moment is being saved for other things. If this would make an improvement then its something I could do myself (providing I can get the parts) Quote Link to comment Share on other sites More sharing options...
porter_jamie Posted June 4 Report Share Posted June 4 Are the cush drive rubbers fucked? Quote Link to comment Share on other sites More sharing options...
Alpinestarhero Posted June 4 Author Report Share Posted June 4 1 minute ago, porter_jamie said: Are the cush drive rubbers fucked? No - I had them checked when the tyres were changed, the mechanic was confident they were in good condition. The chain is good too (correct tension, no major tight spots). I know yamaha's can be a bit shit, and the FZ1 was notorious for a snatchy throttle especially the earlier ones. 1 Quote Link to comment Share on other sites More sharing options...
TLRS Posted June 4 Report Share Posted June 4 How does one check cush drive rubbers. Check for play or how soft the rubber is.. Any chance there is a throttle position sensor fooling the ecu? Telling it the throttle is closed when it's already open a bit. Quote Link to comment Share on other sites More sharing options...
David W Posted June 4 Report Share Posted June 4 I doubt it’s anything to do with the PAIR system unless there’s a leak. 1 Quote Link to comment Share on other sites More sharing options...
Alpinestarhero Posted June 4 Author Report Share Posted June 4 2 hours ago, David W said: I doubt it’s anything to do with the PAIR system unless there’s a leak. I did figure this. There could be some leaks now, it is old and it wouldnt suprise me if some of the hoses had now perished a bit. I think, in all honesty to myself, I should plum for a reflash. Wont be this year, maybe next year. Is Dave Wood Racing reputable? My bike is listed on his website as being able to be worked on. Quote Link to comment Share on other sites More sharing options...
Alpinestarhero Posted June 4 Author Report Share Posted June 4 3 hours ago, TLRS said: How does one check cush drive rubbers. Check for play or how soft the rubber is.. Any chance there is a throttle position sensor fooling the ecu? Telling it the throttle is closed when it's already open a bit. I dont think it would be that, else I would get some erratic engine issues or idle issues? 1 Quote Link to comment Share on other sites More sharing options...
TLRS Posted June 4 Report Share Posted June 4 1 hour ago, Alpinestarhero said: I dont think it would be that, else I would get some erratic engine issues or idle issues? Hmm might do yes. Though maybe it sticks to the idle map for too long. Did the problem occur suddenly or gradually? Quote Link to comment Share on other sites More sharing options...
Halvasso boy Posted June 4 Report Share Posted June 4 (edited) Boss man had one of those a few years ago . He said the same thing. It's appears to be something to do with the fuel cut on a closed throttle. As far as I know, they only way to eliminate it is a reflash. Edited June 4 by Halvasso boy 1 Quote Link to comment Share on other sites More sharing options...
426hemi Posted June 4 Report Share Posted June 4 (edited) There’s a throttle body sync procedure for them apparently, I know my rsv was snatchy before it was done, it usually affects them at small throttle openings just when you’re tapping on the throttle. You can also get blanking plates for the pair system, I’ve done it on all my bikes, it’s a bullshit system really and fakes a cleaner reading which I believe doesn’t help with setup if you’ve got a sniffer in the exhaust. Edited June 4 by 426hemi Add extra 1 Quote Link to comment Share on other sites More sharing options...
nampus Posted June 4 Report Share Posted June 4 (edited) I'm with @Halvasso boy on this one. Have a google on "injector decel cut" Disabling Injector Decel cut: With the injector decel cut active when you close the throttle the injectors shut completely off. Rolling the gas back on results in a delay and then a bump as the injectors turn back on. Disabling it smooths out on/off throttle response at slow speeds. Yamaha are sort off notorious for this, it's an issue on a lot of their bikes. My Tracer had it as well, you need to be very delicate on the throttle to get a smooth transition from throttle closed. Edited to add: If money is tight this might be an option: https://www.wizperformance.co.uk/product-page/2006-2014-yamaha-fz1-ecu-flash It's never going to be as good as a custom made map on a dyno, but it gets you 99% there for a fraction of the price, and it will get rid of that off-on snatch. Edited June 4 by nampus 3 Quote Link to comment Share on other sites More sharing options...
Alpinestarhero Posted June 5 Author Report Share Posted June 5 10 hours ago, TLRS said: Hmm might do yes. Though maybe it sticks to the idle map for too long. Did the problem occur suddenly or gradually? o be honest, it's always been there. I'm just getting more and more irritated by it - erhaps my new-found confidence as my physical health has picked up has brought it all back for me, and my age means I've little tolerance for things that annoy me 1 Quote Link to comment Share on other sites More sharing options...
Alpinestarhero Posted June 5 Author Report Share Posted June 5 (edited) 10 hours ago, Halvasso boy said: Boss man had one of those a few years ago . He said the same thing. It's appears to be something to do with the fuel cut on a closed throttle. As far as I know, they only way to eliminate it is a reflash. Ah, ok - I'll read up on this. 9 hours ago, nampus said: I'm with @Halvasso boy on this one. Have a google on "injector decel cut" Disabling Injector Decel cut: With the injector decel cut active when you close the throttle the injectors shut completely off. Rolling the gas back on results in a delay and then a bump as the injectors turn back on. Disabling it smooths out on/off throttle response at slow speeds. Yamaha are sort off notorious for this, it's an issue on a lot of their bikes. My Tracer had it as well, you need to be very delicate on the throttle to get a smooth transition from throttle closed. Edited to add: If money is tight this might be an option: https://www.wizperformance.co.uk/product-page/2006-2014-yamaha-fz1-ecu-flash It's never going to be as good as a custom made map on a dyno, but it gets you 99% there for a fraction of the price, and it will get rid of that off-on snatch. That is EXACLTY the feeling I'm getting. It probably is that then - well, I suppose I could spend my money on worse things. So no quick and easy fix, which is fine as I wouldnt want to throw my money at things that wont work (although maybe the PAIR removal is a good idea anyway as part of a wider upgrade?) edit to add: thanks for the brainstorming and the info and the advice. I will check over some other bits anyway (vacuum hoses etc), but I'll also save up some money and get it done properly. As far as I feel right now, I'm not getting rid of the bike any time soon. Edited June 5 by Alpinestarhero 2 Quote Link to comment Share on other sites More sharing options...
Thunderbolt Posted June 6 Report Share Posted June 6 BSD Quote Link to comment Share on other sites More sharing options...
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