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Discussion Starter · #1 · (Edited)
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I love it. sounds great. I will try and get some video of it later today. sorry I dident do unboxing pics phone died last night when I was installing it, also installed graves block off plates. next week going to a dyno to get tuned. I dident remove the charcoal canister yet though. I dident know if I was going to have to re rout lines and it was late. I will get some better pics soon also
 

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Looks good :) But I have to admit, the lack of balance pipes on the headers bothers me more than it probably should. It just doesn't "look right" to me, just being honest. Have fun with it though!
 

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Discussion Starter · #4 ·
Looks good :) But I have to admit, the lack of balance pipes on the headers bothers me more than it probably should. It just doesn't "look right" to me, just being honest. Have fun with it though!
Yea it was bugging me also for awhile, I did some research and found some people love them and some go out of there way to remove them. It was a deal for me. They were originally going to use my bike for mach up but that fell through. But it worked out in the end and im happy. I personally like the crossover pipes though.
 

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Why do you think the OEM design has S-shaped headers...and all of the aftermarket systems pretty much go straight down?
 

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Yeah its funny if the bike hadnt come with crossovers we wouldnt notice but since it did it kind of looks like something is missing. Looks good though!

Yea it was bugging me also for awhile, I did some research and found some people love them and some go out of there way to remove them. It was a deal for me. They were originally going to use my bike for mach up but that fell through. But it worked out in the end and im happy. I personally like the crossover pipes though.
 

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Also, it's a way of increasing the length of the primary tubes. Longer tubes are "tuned" for a lower RPM than a short tube is, and that's something they were shooting for with this motor.
Unequal tubes for unequal velocity stacks?
 

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Congrats Dan, can't wait to see and hear them in person. Once I get my bike back from Zero Gravity we'll have to meet up for a ride.
 
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Shorter headers produce more top end and longer headers produce more low end. I think yamaha did a great job with the stock exhaust and I love the sound so I will stay with the stock setup and my neighbors will still talk to me. RR:cool:
 

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Shorter headers produce more top end and longer headers produce more low end:
Technically speaking, why is that? What is the physics behind this?
 

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Don't know for sure but I think it has to do with how fast the exhaust gases exit the combustion chamber I know more back pressure produces more low end. RR:cool:
 

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Technically speaking, why is that? What is the physics behind this?
It's all about pressure pulses and harmonics. Longer or shorter tubes have different "frequencies", which produce a scavenging effect at different RPMs. The scavenging essentially acts as a fifth cycle in a four-stroke engine, the negative pressure through the exhaust port actually causes a supercharging effect and can fill the cylinder past 100% volumetric efficiency (Like a vacuum "sucking" extra air and fuel into the cylinder). The intake can be tuned to do the same thing as well, with positive pressure. Really neat stuff. Of course it's complex, with tons of variables involved. I don't have any good links off the top of my head for how the exhaust pulses work, but here's one for the intake, it's the same principle: Intake tech..... Did you ever wonder how they ....


And I just always feel the need to correct people whenever I hear this, so no offense to you redrider but that's not exactly true. More back pressure never produces more power, that's a myth. It just seems to follow that correlation, because smaller diameter tubing (with more backpressure) will have a higher velocity at low RPM than a larger diameter tubing, and therefore flow better at low RPM and produce better low end power. Higher velocity will always make the best power, but you have to compromise between optimum velocity at a low or high RPM. Tuning for low RPM torque, vs tuning for high RPM horsepower in other words
 

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Imagine that when the exhaust valve open, it let exit a ball of fire. When that ball of fire reach the collector it create a vacuum to the other 2 primary pipe (in our case) If the "ball of fire reaxh the collector at the same time the next exhaust valve open... it scavenge the exhaut better... and help initial charge on fresh fuel during overlap.

That all work good on paper and in a very narrow rpm range, usually peak HP.

You can add variable intake stack in the pile or in our case 3 different length to try to maximize a wider range of rpm.

Its the short version of a long story book... but thats about how it goes. Cross over tube are there to improve the scavinging effect at lower rpm... but not sure how much it really help?

Over the years I seen it all. Step headers and all that stuff.

Sent from my SAMSUNG-SGH-I337 using Tapatalk
 

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Great answer I have read that before but didn't remember all the details. I know intake and exhaust gets very high tech I was just trying to make it simple. Like I've said before I think Yamaha did a great job and the stock setup works great for me it pulls very clean from bottom all the way to a great top end. Thanks for the great answer. RR:cool:
 

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Discussion Starter · #18 ·
Well I just got word from the shop/dyno that they were able to get 109 hp out of the bike, they said it would be possible to get more but its risky and dont reccomend. They also said that they made huge improvements on 0 to 20% throttle. I pick it up tomorrow im excited. Shout out to cyclemall thanks guys
 

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Well I just got word from the shop/dyno that they were able to get 109 hp out of the bike, they said it would be possible to get more but its risky and dont reccomend. They also said that they made huge improvements on 0 to 20% throttle. I pick it up tomorrow im excited. Shout out to cyclemall thanks guys
Post up the uncorrected before and after dyno results when you get the bike back if you get a chance, would love to see the graphs including A/F.
 

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Discussion Starter · #20 ·
Post up the uncorrected before and after dyno results when you get the bike back if you get a chance, would love to see the graphs including A/F.
I will post whatever graphs they give me for you guys to see. I changed my mind im picking it up today, getting off early to go pick it up.
 
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