Programmer... no loss of power when letting off the gas?

My very top end feels a lil weak compared to the build up in the mid range. IE the bike feels like it likes to be shifted several thousand RPMs before redline... but I've also noticed when I'm running wide open, as I roll off the throttle it doesn't immediately lose power until the throttle is rolled a ways, the first little bit doesn't result in an immediate loss of acceleration. You only really notice it since when you roll off the throttle you usually relax your body a little or get ready to compensate for the pending deceleration, but that first bit off rolling off the throttle the acceleration stays steady or maybe even increases a bit, its hard to tell.
That makes me think perhaps my WOT setting is sub-optimal. Do you guys think that would mean it was rich or lean? I will have to wait until after work to read my settings but I wouldn't have set the third number higher than a 2, and most likely its either 1 or 1.5.

Mods are:
Programmer (obviously)
no airbox door - holes in side panel
no-toil filter kit with screenless cage
FMF powercore exhaust with quiet insert.

On that note, by seat of the pants I would say no-toil filter and holes in the side thing made as much of a difference as taking the air box door off did initially. Meanwhile putting the quiet core insert in made no difference I could feel other than responsiveness.

You sure the push-pull cables on throttle are operating correctly?

Any slack in one of the cables?

Try the 3rd # on .5
Its been proven on a dyno that the bikes a tiny bit rich at wot with a pipe, opened airbox and no programmer, adding more fuel at wot adds a tiny bit of midrange punch but hurts the top end.

Thats what I always used to run it at, but I had knocked it up to 1.5 because I was scared I might burn it up running WOT for an hour or so at 80+ every now and then. I took it back down to 0.5. Still feels like im losing acceleration when I let it rev all the way out, but the throttle is linear again.

That's how the bike runs:

Power tapers off before you get to the rev limiter.
It's one of the ways long-term reliability is designed into the engine and gives you a chance at being able to hit tens of thousands of miles on the road without an engine explosion or overhaul.

YZEtc wrote:

That's how the bike runs:

Power tapers off before you get to the rev limiter.
It's one of the ways long-term reliability is designed into the engine and gives you a chance at being able to hit tens of thousands of miles on the road without an engine explosion or overhaul.

I'm not going to disagree completely, but it FEELS like my bike pulls right up to the limiter in lower gears. I have my settings fairly lean, and many times I have bounced off the limiter hoping for a few extra RPMs as it keeps pulling strong. I have to double check my settings, since i had it programmed for winter riding, but I think it was like 2.5-2.5-0.5 something something something. The pipe always has a light black coating on the inside, and my backpack usually smells a bit like fuel. I haven't actually checked the plug, but I don't think it is running too lean (at least when it is cold out and the stock map runs rich).

I just re-read your original post, sounds more like a throttle cam issue which I notice as well. WOT actually happens before the physical throttle tube is turned to the stop. I was thinking of trying a short turn throttle.

dmmcd wrote:

YZEtc wrote:

That's how the bike runs:

Power tapers off before you get to the rev limiter.
It's one of the ways long-term reliability is designed into the engine and gives you a chance at being able to hit tens of thousands of miles on the road without an engine explosion or overhaul.

I'm not going to disagree completely, but it FEELS like my bike pulls right up to the limiter in lower gears. I have my settings fairly lean, and many times I have bounced off the limiter hoping for a few extra RPMs as it keeps pulling strong. I have to double check my settings, since i had it programmed for winter riding, but I think it was like 2.5-2.5-0.5 something something something. The pipe always has a light black coating on the inside, and my backpack usually smells a bit like fuel. I haven't actually checked the plug, but I don't think it is running too lean (at least when it is cold out and the stock map runs rich).

I just re-read your original post, sounds more like a throttle cam issue which I notice as well. WOT actually happens before the physical throttle tube is turned to the stop. I was thinking of trying a short turn throttle.

Could just be different motor mods and how the motor reacts to them. IE, here is a chart on HMFs page for their pipe vs stock. Well, my power curve feels more like the graph they have for stock, making me shift at about 9.5k or so. Mine actually felt more like their "piped" graph's shape before I did all the airbox stuff.

Mine will pull right to the rev limit in the lower gears on hard ground, but in the higher gears or in sand it wont hit the limiter without holding it wfo and waiting for it, the bike pulls the hardest if I shift a few 100 rpms before hitting the limiter.

I dont mind this at all as it keeps me riding in the mid range more and from revving the motor to death.

I the fmf power bomb header adds top end power if you want it to pull harder up there.

I got around to repacking my exhaust. I regained a lot of power and it revs out better now. On the highway it accelerates worlds better between 70 and 80. I think the big burnt out spot at the top of the can must've been messing with high rpm flow.

oic0 wrote:

I got around to repacking my exhaust. I regained a lot of power and it revs out better now. On the highway it accelerates worlds better between 70 and 80. I think the big burnt out spot at the top of the can must've been messing with high rpm flow.

Very interesting. I hadn't considered the performance aspect of the packing, thought it was just for sound, but it makes sense that it screws with the flow once the packing is gone or gets 'holes' in it.

In my silencer, all of the packing in the top portion beyond the halfway point was gone. Repacking really didn't make it any quieter except at idle.

The biggest thing I can feel is at a displayed ~60mph in 6th gear, if I roll in to the throttle it picks up and goes nicely getting to a displayed 70 in just a few seconds and 80 in a few more (which would be a true 73, how fast I go down the highway). It probably used to do that but it had gotten pretty sluggish at the higher speeds and my fuel economy had dropped down to the low 50s. Hopefully my fuel economy will get back up into the 60s with the new found grunt (which means I can cruise at lower throttle settings and don't need to downshift as often). My fingers are crossed.