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Discussion Starter #1 (Edited)
At the moment, my bike has a custom AF map. Out of curiosity, though, aside from the top speed being limited and all the other stuff, how restricted is this bike in terms of horsepower numbers? I've read from multiple sources that the secondary throttle valves close a bit and that the ignition timing is retarded (for the purpose of passing emissions requirements) at the top end at the lower gears (or maybe even the upper gears?), thus some of the potential horsepower is corked up. Also, for those of you who have flashed your ECU, what were the results?
 

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the main restrictions are in 1st t0 3rd the ignition is retarded in the lower to mid rpm range and yes with a flash that's removed as well as secondary throttle plates opened up
 

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Discussion Starter #3 (Edited)
Thanks for responding, frocket. When you say the secondary throttle plates are opened up, do you mean at the top end of the rev range or the low to mid range where the ignition is retarded? (thus the retardation because the valves are closed a bit) Are the plates closed a bit even at the higher gears? Have you flashed the ECU on your bike? I have looked at the Woolich kit with the autotune/auto log box and the Flash Tune kit, but I feel I need to do more research on them.

Is there anyone here with experience on either or both? I'd like to hear your opinions or reviews.
 

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Note that the so-called restriction in the lower gears, that is the change in ignition timing affects only mostly-closed throttle operation and relatively low engine speeds. I'm not entirely sure what its purpose is (though I would guess increased engine braking) and though it might lower engine output under those conditions, I think one can hardly call something a "restriction", if it happens mostly while engine-braking and all you have to do to overcome it, is open the throttle a few degrees more. Similarly, charge intake is generally significantly more complicated than "more open is better", hence not fully open secondaries might well have other purposes, than restricting output (although that sounds more likely to be intended for restriction that the ignition timing changes in lower gear maps).
 

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Thanks for responding, frocket. When you say the secondary throttle plates are opened up, do you mean at the top end of the rev range or the low to mid range where the ignition is retarded? (thus the retardation because the valves are closed a bit) Are the plates closed a bit even at the higher gears? Have you flashed the ECU on your bike? I have looked at the Woolich kit with the autotune/auto log box and the Flash Tune kit, but I feel I need to do more research on them.

Is there anyone here with experience on either or both? I'd like to hear your opinions or reviews.
no I havnt yet had a flash on my L4 as I am also looking into the best way to go from what I have been told that the gear based ignition restrictions is in the 1st 3rd of throttle and makes quite abit of difference when removed my understanding is the throttle plate opening up more is in the mid to full rpm range cheers
 

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Discussion Starter #6 (Edited)
Thanks guys! Coincidentally, having checked out motorcycle.com this morning, to my surprise they currently have a short explanation on the reasons for the power restrictions. Click on the link below.

Where?s the Missing Horsepower?

Anyway, I've had this bike since I bought it brand new; it was purchased in 2009. And to this day, even with the current literbikes, I still love my K9. Aside from just being fast and nimble, its appearance, to me, doesn't look dated in the least bit.
 

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I'd always thought that the timing retard was on the 1000's, and in the first 3 gears to make it more 'streetable'- wheelie a git less and not slide out as much when accelerating in tight corners, etc.
I have seen dynos that proved this to be true- sorry, no link to it right now.
I also do NOT know for sure which bikes have this.

I will say that now having 2 K5 1K's, (like that better skid?), the one with the Bazzaz Z bomb TRE is more jittery/wheelie prone - both with the same gearing, no SETA valves, and aftermarket mufflers. K5 didn't have a Cat. The TRE = timing retard Eliminator.- thus giving it a bit more in the first 3 gears. I think it also removes the top end limiter too?

A good flash will do this and more as well.
 

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Discussion Starter #10 (Edited)
All right guys. Brock Davidson just posted this video today of his 2017 GSX-R1000 project bike. The video shows that at least for the new Gixxer literbike, with its throttle-by-wire system, it is indeed restricted and that the throttle blades close quite a bit and limit some of the power (in my opinion, a huge amount) the bike is capable of putting out. The way he proves this is by far, personally, the best way of doing so--by catching it on video and including empirical data to go along with things. Anyway, in the video, Brock also flashes the ECU (using Flash Tune) to remove the restriction and shows the results after doing so by putting the bike on a dyno. Click on the link below.

 
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