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Discussion Starter #1
Well, after a couple of quick emails to Tom at Biohazard A LeoVince full system found it's way down to the lower end of the planet... (Thanks Tom)
Looks good, and took about 15min to fit.
So far have tried it with the 32mm tip/without dB killer and boy does it change the power. It rev's clean, and feels like a different bike. It's loud on the bike, but not to bad, and my wife thinks it's ok on a ride by.. Think the 40mm tip would be track only.
I have put the dB killer in to quieten it down, and it is only slightly louder then the stock muffler, but it does knock the top end free reving back down to a similar level to the stock muffler.
 

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Very nice, keep the tip in and do a vid if you can.

You'll find the more you ride it (at full revs on the open highway) the ECU adapts and it will rev cleanly after a few hundred km.. these bikes seem very sensitive to air fuel ratio.
 

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Discussion Starter #6
How about the baffles how often do you replace those on that brand? Look the silver look.
It's a straight through muffler, no baffles, so not a lot of stress on anything.
I don't imagen that it will need to be repacked for a long time.
 

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It's a straight through muffler, no baffles, so not a lot of stress on anything.
I don't imagen that it will need to be repacked for a long time.
Awesome! Is this a slip-on, or a full system muffler? There is a distinction between these two, right? So glad the power is a noticeable difference. I'm thinking of getting one of these. May I ask the model No., and how much did it cost? I followed you on the other thread-- been waiting to hear about it. So glad you posted!
 

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What is a straight-through muffler?
 

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I'm wondering whether to spend the money on this muffler you've got there, or more track time. Any thoughts, guys?
 

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Discussion Starter #10
Complete system from biohazzard Model 8560.

LeoVince

Straight through means that if you look into the muffler, you can see staight through, no baffles. Yes, on a track it would be a big help. It gives you more top end power for better speed & acceleration. And a big weight saving too.
 

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I'm wondering whether to spend the money on this muffler you've got there, or more track time. Any thoughts, guys?
The std muffler will ground out on the rhs as you get you knee down.
It happened to a poster here. plus it weighs 10kg.
 

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The std muffler will ground out on the rhs as you get you knee down.
It happened to a poster here. plus it weighs 10kg.
BTW, Aufitt, that was an awesome video. Back to the matter at hand: what do you mean by this, "will ground out on the rhs", and what's the rhs?
 

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Discussion Starter #17
So, after several tanks of testing I found out that the best way to get better performance has got more to do about the Fuel injection & ECU than the exhaust. This is a non scientific test, but after changing between the stock exhaust and the LeoVince full system a few times it became very clear. As far as ECU re setting goes, I simply disconnected the battery for 45min at each exhaust change & ground out the terminals to remove any power in the system.
First, when I put the Leo on the bike ran very lean. It had no bottom end, almost no midrange, but had better top end power due to the non restrictive exhaust. It took a couple of days, but the ECU re-mapped and the power was back, running sweet, strong bottom end & midrange, and going a lot faster, revving easier than when stock. The bike was great. Now I started playing.
I pulled the Leo off & put the stock exhaust back on. The first thing I noticed was, Wow, there is not much difference? I don’t remember the stock exhaust being this good. It had good low & midrange, but it was revving clean up to about 10,000rpm, and it’s never done that before, it always slowed down from about 8,500rpm. It was also using more fuel, but going a lot better, the reason, THE ECU had richend the fuel map when the LeoVince was installed. After a couple days it slowed up, and started to feel restricted again as the ECU leaned the bike off back into commute mode. Obviously the ECU is looking for a specific fuel/air target. By fitting the Leo the ECU has to add more fuel to achieve target, and because it is more efficient than the stock muffler I didn’t notice any big MPG changes with the leo. Based on the running I did it looks something like this. Stock bike around 77MPG, Leo around 70MPG, with the stock back on and rich ECU around 60MPG. (Now this is non scientific, just what I put back into the bike. And as it was going really good I was probably giving the throttle cable a workout too)
So my unscientific results are telling me that, as expected, Honda have the ECU set to map for economy/emission, not performance. That putting a Slip on or Full exhaust system does make a difference, but the ECU is still looking for economy, not performance. If you want performance I would start with the ECU and not the exhaust. If you want to change the look of the bike and don’t care about maximum performance just change the exhaust, it does go faster. If you want to get the best out of the bike, change both...
 

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So, after several tanks of testing I found out that the best way to get better performance has got more to do about the Fuel injection & ECU than the exhaust. This is a non scientific test, but after changing between the stock exhaust and the LeoVince full system a few times it became very clear. As far as ECU re setting goes, I simply disconnected the battery for 45min at each exhaust change & ground out the terminals to remove any power in the system.
First, when I put the Leo on the bike ran very lean. It had no bottom end, almost no midrange, but had better top end power due to the non restrictive exhaust. It took a couple of days, but the ECU re-mapped and the power was back, running sweet, strong bottom end & midrange, and going a lot faster, revving easier than when stock. The bike was great. Now I started playing.
I pulled the Leo off & put the stock exhaust back on. The first thing I noticed was, Wow, there is not much difference? I don’t remember the stock exhaust being this good. It had good low & midrange, but it was revving clean up to about 10,000rpm, and it’s never done that before, it always slowed down from about 8,500rpm. It was also using more fuel, but going a lot better, the reason, THE ECU had richend the fuel map when the LeoVince was installed. After a couple days it slowed up, and started to feel restricted again as the ECU leaned the bike off back into commute mode. Obviously the ECU is looking for a specific fuel/air target. By fitting the Leo the ECU has to add more fuel to achieve target, and because it is more efficient than the stock muffler I didn’t notice any big MPG changes with the leo. Based on the running I did it looks something like this. Stock bike around 77MPG, Leo around 70MPG, with the stock back on and rich ECU around 60MPG. (Now this is non scientific, just what I put back into the bike. And as it was going really good I was probably giving the throttle cable a workout too)
So my unscientific results are telling me that, as expected, Honda have the ECU set to map for economy/emission, not performance. That putting a Slip on or Full exhaust system does make a difference, but the ECU is still looking for economy, not performance. If you want performance I would start with the ECU and not the exhaust. If you want to change the look of the bike and don’t care about maximum performance just change the exhaust, it does go faster. If you want to get the best out of the bike, change both...
You are a bright man. I like the tests you ran. Your conclusion seems to make sense. I'm going to show this post around to the guys at the Honda store, keeping in mind it might be over their heads.

Here's a question. How do you re-program the ECU, without installing a new exhaust system? And, what do you think of the Power Commander? Would that make it easier to tune for performance rather than economy/emission?
 

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Discussion Starter #19
Here's a question. How do you re-program the ECU, without installing a new exhaust system? And, what do you think of the Power Commander? Would that make it easier to tune for performance rather than economy/emission?
I am not sure if Honda have made the stock ECU adjustable? A Honda dealer may be able to download different maps into the stock unit or adjust the settings???. I guess it's early days for dealers with this bike too, and not a lot of info is around.
Otherwise I am thinking about this unit:
BAZZAZ BPD ZFI Z-FI FUEL MAPPING KIT Z-Fi CBR250R 11 Z-Fi Fuel Control Unit. F343
But for now I am happy to just have the LeoVince on the bike. It is ticking all the right boxes for me, and I don't really need to spend the money to make a little bike go a little better :)
Think I'll spend it on some frame sliders and a fender eliminator kit instead...
 

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I like the look of the leo's. I have the yosh full carbon exhaust with the bazaz z-fi and definately noticed an increase in torque and smoother throttle control. Love the sound. Enjoyed your results of stock vs new exhaust. Similar results of what my system has acheived
 
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