This is for Rook and/or Hub because they always have the answer to my question. I just put my M4s on the other day. Before I put them on My odometer was at 0 just before I took off. I usually shift at about 4- 5000 rps just cruising through the city. Now that I have my slip ons the rps start almost at 2000rpms causing me to shift about 6-7000rpms. Why is it higher starting off where I have to shift at 7000 rpms? Is that a good or bad thing? Mind you, I'm not racing or pushing it hard. Just cruising. Just wondering if its hurting it or what.

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You mentioned your odometer was on 0? I'm not seeing the significance of a trip meter or odo in this account. I see your concern with the shift in the power band but that is not altogether unheard of. Now that the exhaust flows more freely, you feel some loss in low rpm power but no doubt you have increased midrange and top end. I can't say that I noticed any real difference in low end grunt with my system and mapping but some people say it happens. The 2000 rpm difference in your case seems quite large. I am guessing there may be a mapping issue?? If it runs real smooth, i would say it may just be characteristic of M4s.

Though I never owned them, I always liked the M4s for slipons. Never heard that they caused such a decrease in bottom end power. I think you should talk to some others who have had M4s to see if what you are experiencing is typical. If so, and the shift in power to midrange is bothersome, I would recommend going to a good full system as long as you can get a map. OR ask about performance loss from low end on various Brocks system and Akrapovick. I asked years ago and there was no one who told me they had a noticable loss in low end performance fom a full system. I think slipon owners are the ones who perpetuate that story.

So that gets us wound up on the slipon vs full system vs stock exhaust debate. Let's hear it boys!

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Wooow! Well I didn't get the bike mapped. I just sliped the pipes on. I was told it wasnt mandatory to get the bike mapped with slip ons. I really wasn't looking for performace just a little sound. I didn't lose anything when I hit the throttle. It damn sure does shift a hell of a lot smoother I can say. I was just wondering. You guys help me out a lot.

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There you go. Hub has it. Well thank you friends for the information.
i wilk keep her just like she is.

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I've never run the bike without a PC since I had stock cans. Can't tell you how the bike would run w/o a PC and w full system cuz I never tried. I like the change I got from accepting my first Autotune suggested trims. Leads me to believe there is a difference between running on the stock map and running on maps made by tuners.

I recently had the pleasure to meet as very talented racer. He races for prize money so he's not just some schmuck track hound. He told me he has never used a PC for his full systems on his ZX-10s. Stock map all the way. Of course his bike almost never sees anything under 7K rpm if that would have anything to do with it.

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That's amazing that the zx10 guy beats people with a stock bike. I've only been riding for 2 years. Stock not to mention. Jumped from a zx6r to the loving zx14. Just because of my size. All my co workers have a bike. That was the main reason why I got one. I was always told by experienced riders that its not about the bike its the rider that makes it fast. From what rook told us about him. It seems to be true.
O yeah I meant to tell you Rook, I took it on the interstate yesterday and it seems like from first to third gear is where my rpms are a little higher. When I switched to the fourth gear everything seem to be the same as if I where riding stock pipes. Its nothing wrong, but just sharing some information. Like I said I don't know shit about bikes, but changing the oil and putting lube on my chain. I'm learning so much on this site.

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That's amazing that the zx10 guy beats people with a stock bike.

It was the stock aif/fuel ratios I was talking about. He did not change those with a PC to adjust for mods. actually, the bike is a dedicated track bike so at the very least, it has a pipe and race fairings. Who knows what else--. He had a crash that day I met him so he may have a new onr now. IDK, you could tell by the hasty bondo work that he had been down more than once. The reaeserts were snaped off too. All the better for cornering clearance-shorter peg = more toom to lean. lol

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I'm considering some slip-ons for two reasons, the first being the most important; The heat coming off these cats. The thermometer on my patio today topped 117, and this exhaust is a leg-roaster. (And I'm not crazy about the overly long (to my eyes) stock cans)

The second reason, I'm not as certain about. I have a ZZR1200 w/D&D slip ons, and that f'r is loud. I'd like a little more growl than stock, perhaps, but I'm going to go for full-length silencers with a fairly mellow/deep tone if I do a change.

For a pretty conservative/quiet slip-on, I have to believe that the air-fuel mixture would remain so similar that the stock tuning/02 sensors would cover that difference easily. Sure can't see holing a piston, but even wonder about any signifcant change in the torque curve. There is an exhaust dyno-comparison elwhere on this site, and both slip-ons and full systems were tested with no reported freakouts in AFR with the computer tuning as stock.

But I'm really surprised by the OP's assertion that slip-ons alone moved his powerband up 2,000 rpm. I know that the change in sound alone will sometimes cause a change in the way we throttle/shift the bike; where we like to hear it, as it were.. Could this be a more plausable answer? I do like the bottom-end grunt of this 2010 model..

For a pretty conservative/quiet slip-on, I have to believe that the air-fuel mixture would remain so similar that the stock tuning/02 sensors would cover that difference easily.

I would think so. M4s are not that,,however. LOUD!

I know that the change in sound alone will sometimes cause a change in the way we throttle/shift the bike; where we like to hear it, as it were.. Could this be a more plausable answer?

2009,..maybe you are enjoying the sound so much you don't even want to shift at conservative rpm anymore.
hehe, I was the opposite for some time after going to the Cannon. I felt like I was drw=awing everyone's attention with the noise........and I was right. I just don't give a rip now that I am used to it. I put my earplugs in and love the sound of my pipe all the way up past 100 i still hear it over the wind on my lid.

* Last updated by: Rook on 8/8/2011 @ 3:47 PM *

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@ zx142009......I was goin to ask the same question, just like u I'm not looking for anymore HP just wanted a better Lil-sound.........hope u don't mind?

But my bike is an 07 wit dual muzzy, everything else stock.

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So, guys, what is the general concensous as to the need to tune just for slip-ons (any slip-ons), leaving the cat in the stock header collector? I took a ride last nite, still over 100 here in the evenings, I gotta get these cats away from my feet!

Yes cjuni I have been debating on which pipes to get for a whole year and I finally got the ones I wanted. I have been listening to sound clips on youtube and everyting. Comparing the deep sound two brothers and m4s to the somewhat high pitched yoshi. The m4s are real deep. So from 1st the 3rd gear is when they are the loudest. Now Rook, your freaking pipes are loud if you can still hear them through the wind at 100. All I could hear is the wind with my m4s at 100. Even if I had the german helmet on they still weren't that loud. Now I will tell you cjuni I still haven't lost any horsepower at all. It still feels the same to me. My take off is the same. Like I said earlier the only difference is the start of the rpms. One of the main reasons why I got some slip on was becasue of the look. I didn't want to see those cannons anymore either. All may co workers were making fun of me saying I ride in silence. Not anymore. I'm loving my M4s.

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Now Rook, your freaking pipes are loud if you can still hear them through the wind at 100.

....with full face lid and WITH earplugs in!

I don't hear those pipes even start to get drowned out
we talkin' the SH!T is LOUD!

* Last updated by: Rook on 8/9/2011 @ 2:56 PM *

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Ok guys so from all the info posted I'm goin to say that in a around about way yes we should get a PC & tune the bike even wit slip-on's.

* Last updated by: cjuni on 8/9/2011 @ 4:18 PM *

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I would run about any exhaust on a Gen2 w/o a PC because they are mapped very rich throughout powerband (so I have been told). I believe the performance enhancements will be maximized by the use of a PC with any exhaust but that does not mean the bike would not be great on the stock map.

The 06-07 was the one that you had to watch for running lean all the way up to 6000 rpm. I would only be comfortable running a PC with a proven map in a Gen 1 bike. Just to be safe. You may be fine w/o a PC especially with slipons but out of the many threads I have read on this topic over the years, a PC with any engine mods is overwhelmingly recommended as the "safe" way to go regardless of the year.

Never heard of anyone burning the bike up by running slipons w'o PC though....or a full system for that matter. Turbo- probably be a problem w/o a PC.

* Last updated by: Rook on 8/9/2011 @ 4:36 PM *

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@ Rook.......thanks again!

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Yeah Rook those sound so good. It makes me want some. But I can't afford it so I'll stick with mines for now. That was a nice camera angle too. What speed did you get up to? And Hub you a funny guy.

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Rook, I have to believe that what you say here is true. I've found most "modern" bikes (and cars) are tuned on the rich/safe side, and realize an increase in power by leaning out within safe perimeters. At some point, I'll either remove the header cat, or install a full system, and I'll want the bike tuned on the dyno to get most out of that. But with less than 200 miles on the bike so far, I'm less inclined to worry with those mods right now. Just wanna ride...

Your bike looks/sounds awesome, BTW. My ZZR1200 is the same color, and I've always been partial to it..

Thanks. whoever is on that bike is doing about a buck sixty buck sevety.

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Damned neigborhood kids...turn your back for a single second...

Wow. That guy was going pretty fast. Blink and would have missed him.

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you know it. neighborhood kids. crazy lil bastages are out of control.

* Last updated by: Rook on 8/9/2011 @ 10:24 PM *

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Rook, love those roll-ons from the vid. Elegant.

you know it. neighborhood kids. crazy lil bastages are out of control.

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