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Discussion Starter · #1 ·
Really quite keen on the M4 Street Slayer slip on.

You cut the cat off and effectively make it a full system at the cost of only a slip on. I think it looks awesome, love the fact I doesn't need a rear hanger and sounds great.

I looked at an eBay listing and it said remapping is not absolutely necessary.

Surely it is? You're not going to have anywhere near the same back pressure.

Can the standard ECU just be reflashed to accommodate or will I need a powercommander or of the likes?
 

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You CAN run full exhaust with stock ECU and even disconnect the O2 sensor and the bike will run just fine (maybe not recommended, but it worked for me when my remap decided to go rouge at a recent TD). A remap WILL generally get you more Hp over stock mapping for any exhaust set up.
 

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Disconnect the CO2 sensor? What will it work for? What are the effects of it? Won't it cause ECU looping or any other bad effect? I feel my R3 poor in fuel, even with the stock exhaust.
Will it stop the engine hesitation and help decrease the popping?
Sorry for many questions.

Tks.
 

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In factory trim, I'd not mess with the O2 sensor at all.

I removed the O2 sensor from mine only because I have an aftermarket fuel management ECU (Bazzaz) that doesn't require the sensor - fixed AFV mapping. PCV uses their own O2 sensor and adjusts AFV mapping as you ride. Pros and cons of these systems is for another thread. The Bazzaz took a nap, I reverted to stock, didn't have the O2 sensor with me, the bike fired up, ran fine and didn't even throw a code. I fully expected to get an error code, but didn't. Again, I only tried it because I wanted to salvage a track day, so not generally recommended.

OP asks if stock ECU can be reflashed - I'm sure it can so they can accommodate updates if needed, but have not seen any posts yet on the forum. Most are using either PowerCommander or Bazzaz for remapping as far as I know.
 

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If I just unplug the CO2 sensor, won't it stay with the injection light forever on in the panel?
Tomorrow I'll make the 600 mi checkup, so I'll ask the dealer if is it possible to reflash the stock ECU, or just send 5% or 10% more fuel, than I ansewer it back here.
Thanks.
 

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To be clear, I am referring to lambda sensor on the exhaust pipe. Before just adding more fuel, you should log what you're getting for AFV's - then adjust. Stock mapping was running on the rich side when we logged data initially. I ended up leaning the map up by over a full point, so again - see what it's doing now, then decide if there's room to push one way or the other.

For those who think a remap is the ticket to more power, you're both right and wrong. Properly tuned, it will make more power - true. But we're talking about roughly 3 whopping horses, so spend your coin wisely. For race application, a 10% increase can make a difference sometimes - for street riders on the R3, maybe not so much. (opinions expressed not necessarily the position of this station, buy one get one for no additional cost, may cause irritability, rash or swelling, not for children under the age of 5, may present choking hazard, do not place over head)
 

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What are the AFV's? Here where I live it's very hard to find someone who sell, install or tune up a fuel module, so I need to perform all the tests possible before install a PCV. :(

My R3 has full exhaust and PAIR system blocked. It has a few popping and has a weird little falure when I fast pull the throttle under 6k rpm. All of it was already happening before the exhaust installation. Can it be wrong fuel? Since 0km I'm using the same fuel, from the same brand lol...

I need to check the spark plug gap and than test unplugging the CO2 sensor.
Last option is PCV because it'll give me a lot of work to find, install and tune it, I'll have to do it all myself.

Thanks for your help Mr Stirz!
 

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AFV = Air/Fuel Values
Before I remapped, I ran Yosh full exhaust and had removed smog pump, cali can, and had installed high performance air filter. The bike ran fine. After remapping, I got a wee bit more power. As far as the 'popping' mentioned - this is probably just unburnt fuel igniting somewhere downstream of the engine. Under hard acceleration, then chop throttle, very common and nothing to be overly concerned about. If it does it all the time, could be bad gas but not likely due to full exhaust.
 

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I have a full exhaust and a PCV. I don't see the point in spending the money on a true base level ECU re-map on these bikes. The piggy back PCV does enough I'd say.

I will say that I also have a bit of a stair step in power delivery around 5 or 6k rpms when going from partial to fully open throttle.
 

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r3 running full exhaust Yoshi 77 with db killer installed.I disconnected oxygen sensor Installed PCV and block off plate. The plate is what I believe helped the major popping. As I installed the exhaust first without block off and it popped on the roll off and down shift. Then after I installed block off. It did not pop like it was before. It's good now. Cutting the cat out of the exhaust on the stock pipes and adding a M4 is nice. The full Yoshi 77 are a larger diameter pipe coming out of the bike. Stock are much smaller pipe. I might be crazy but I think my bike runs better on 91 fuel. I was running 87 like the manual says and it did run as smooth after the full exhaust and pcv and block off project. Now it runs smooth.
 

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Really quite keen on the M4 Street Slayer slip on.

You cut the cat off and effectively make it a full system at the cost of only a slip on. I think it looks awesome, love the fact I doesn't need a rear hanger and sounds great.

I looked at an eBay listing and it said remapping is not absolutely necessary.

Surely it is? You're not going to have anywhere near the same back pressure.

Can the standard ECU just be reflashed to accommodate or will I need a powercommander or of the likes?
Question: do you have a block off installed. Stock ecu should work fine it did on my bike with full exhaust, before I installed the PCV
 

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Discussion Starter · #12 ·
Thanks for the replies fellas.

I will probably just run it stock then, and maybe get it tuned up with a PCV a couple of months down the line from fitting the exhaust.

No smog plate fitted, not sure I'd particularly need one, plus part of wanting this system is for the down shift pops!
 

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Hey fellas, got my first bike last week so im still a newbie

Thinking of getting the full yoshi system, i only ride on streets and mainly on weekends. Would it be 110% necessary i have to get the pcv and block off plates?

Would it damage the engine if i didnt? Only because the pcv is like $400 plus the plates are about $50 and plus i will be taking it to a shop for install would probably take a nice chunk of coin off me.

Any info would be great. Thanks boys
 

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Hey fellas, got my first bike last week so im still a newbie

Thinking of getting the full yoshi system, i only ride on streets and mainly on weekends. Would it be 110% necessary i have to get the pcv and block off plates?

Would it damage the engine if i didnt? Only because the pcv is like $400 plus the plates are about $50 and plus i will be taking it to a shop for install would probably take a nice chunk of coin off me.

Any info would be great. Thanks boys
Review previous posts, this thread - question's been answered several times herein.
 

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I just installed my m4 Street slayer this past week along with a pcv and a block off plate. It does seem quite a bit more alive after this when I don't have a baffle in, but I also need to literally wear ear plugs without the baffle in (it is that loud), but it is worth it because it just rides better
 

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I just installed my m4 Street slayer this past week along with a pcv and a block off plate. It does seem quite a bit more alive after this when I don't have a baffle in, but I also need to literally wear ear plugs without the baffle in (it is that loud), but it is worth it because it just rides better
Any vids of the bike fitted with the M4? I'm interested in running the same setup, minus the PCV (for now).
 
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