Coffmans Exhaust the truth.
- Thread starter bikee4
- Start date
Keach
New member
OK, been riding with the muffler to know that it is ineffective as a performance adder and is poorly designed. That being said I would recommend a name brand muffler for the FZ8 that has actually been researched and actually tuned for our bikes.
Care to elaborate on how it's poorly designed? Still haven't rode my bike with it on so I don't really have an opinion other than mine fit nice, looks good, and sounds good at idle. Have you noticed any negatives while riding vs the stock exhaust, ie power loss ect.? I assume you didn't notice an increase in power, but I wasn't expecting that when I bought mine. Just hated the way stock can looked and sounded.
master paper clip
New member
I don't really know what u were expecting out of such a minimalist design, shorty pipes like that don't usually add anything but sound... There not enough of a muffler body to really engineer it to do anything... did it hurt performance or was it just not what u were hoping
bikee4
New member
Well the sound is good, but the bike seems to have lost a lot of midrange power. It feels like a giant hole opened up in the middle I have a smaller R6 baffle and with it some midrange comes back but feels choked on top. This with a PCV and any map including bone stock. Basically my bikes rideability has been reduced. I'm going back to stock exhaust until I can get another slip on muffler.
master paper clip
New member
What maps have u tried
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MotoZen
New member
I might be interested in buying a used pipe if you want to get rid of it.
Sent from my other favorite addiction (Galaxy S3) using Tapatalk.
Of course. There is no back pressure. Back pressure is necessary to have good midrange and low end torque. A longer can will help a little with that but any slip-on that is "straight-thru" is going to hurt your bottom end and mids. If you put in the sound suppressor that might help.
The FZ1 has EXUP which automatically adjusts to provide back pressure, so you can run a slip-on with that bike (same for many of the FZRs, etc. as well as the GSX-R 750) and still keep your midrange/bottom end.
If you want performance just have your ECU reflashed. You can keep your stock exhaust and the bike will be much faster.
http://www.779cc.org/forum/fz8-mods/3933-guhls-reflash-ride-report.html
Most pipes any more are just noisemakers, we can do SO much with the ECU alone that it simply is not necessary to do the whole pipe/dyno thing unless you like the loud sound or the look. To me, having had a hell of lot of bikes with loud pipes over the years (ear-splitting Harley Big Twin among them) I am more into stealth these days, and make up for the difference with conspicuous gear.
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Although "backpressure" isn't technically the correct terminology, it is the widely accepted misnomer for the concept of optimal flow rate of exhaust at different RPMs.
When people mention scavenging it's in regards to how fast the exhaust pulse can get pulled out based on the velocity of that pulse in any given size of piping.
When people mention scavenging it's in regards to how fast the exhaust pulse can get pulled out based on the velocity of that pulse in any given size of piping.
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Woody146
Banned
You already spent the cash..why downgrade?!
MotoZen
New member
Because the Coffman looks amaze-balls! I thought I wanted one, but now I'm sort of reconsidering as well. I'm not a racer, but I still don't want to hurt performance either.
Sent from my other favorite addiction (Galaxy S3) using Tapatalk.
Woody146
Banned
Oh for sure looks dope..I always have wanted a lowmount exhaust..I am not willing to sacrifice performance though..so one of these days I will get the full graves...the longer I wait..the cheaper it's getting..down to 900 and change...maybe it will continue to drop since our bikes aren't made anymore..here in the u.s. At least.
Banky2112
Just plain crazy...
Graves Motorsports Yamaha FZ8 11-12 Full Stainless Steel Exhaust System from SportbikeTrackGear.com
If you call, they will probably give you more of a discount. They are really cool to work with.
If you call, they will probably give you more of a discount. They are really cool to work with.
FZ8Panda
Member
Yea, I'm gonna pass on the Coffman. I wanted it cause I liked the loud sound of it but if it's going to hurt performance than no point in getting it. Looks like I will look into a new helmet or a PCV.
Woody146
Banned
My yamaha dealer has a pretty good relationship too...they both sponsor a local rider annnnd they are California local! I've already had some contact with graves themselves but they are usually pretty busy..(not the biggest company) but I get 15% off parts for life from San Jose yamaha since I bought my bike from them so I'm hopping to get a sweet deal....when I have an extra $900 to blow lol
Coffmans - power loss? Not fair to assume.
I think it is unfair to state that the Coffmans exhaust tip(s) results in an increase or loss of power as I have yet to see a dyno chart showing this to be true or false. I do not find any statement by the Coffman's stating horsepower gains or even power curve promises.
FACT: The Coffman's tip is 14.5 lbs lighter than stock (include all fasteners/brackets) Any weight reduction is directly related to performance gains (small but factual)
FACT/OPINON: It looks very good. I say great.
FACT/OPINON: Is sounds very aggressive and good.
FACT: Dyno charts tell the truth. Without them, do not make claims.
FACT: WSB, MotoGP and Privateers are utilizing data logging, telemetry and support to correctly analyze factual data. The opinion that there is perfect exhaust and ECU map for all scenarios is false. Weather and other factors result in variations of power production.
OPINION: Useable HP; 90% of this community cannot utilize the full power of the bike in stock form. Not a slamming anyone particular, this includes me. I have many years race track experience on several platforms (RZ350, FZ600, GSXR750). There are a lot of variables.
Be fair to those who provide services and goods to the motorcycle community before making statements. Those who provide service and support make this adventure possible.
Buy and utilize products and services with realistic expectations and learn to enjoy the ride.
Unrelated example: Millions of those ionized rubber balance bracelets, shoes that tone your butt and more products have sold and had claims both from the sellers and users stating performance and fitness gains. We all know how that worked out.
dgray5150
I think it is unfair to state that the Coffmans exhaust tip(s) results in an increase or loss of power as I have yet to see a dyno chart showing this to be true or false. I do not find any statement by the Coffman's stating horsepower gains or even power curve promises.
FACT: The Coffman's tip is 14.5 lbs lighter than stock (include all fasteners/brackets) Any weight reduction is directly related to performance gains (small but factual)
FACT/OPINON: It looks very good. I say great.
FACT/OPINON: Is sounds very aggressive and good.
FACT: Dyno charts tell the truth. Without them, do not make claims.
FACT: WSB, MotoGP and Privateers are utilizing data logging, telemetry and support to correctly analyze factual data. The opinion that there is perfect exhaust and ECU map for all scenarios is false. Weather and other factors result in variations of power production.
OPINION: Useable HP; 90% of this community cannot utilize the full power of the bike in stock form. Not a slamming anyone particular, this includes me. I have many years race track experience on several platforms (RZ350, FZ600, GSXR750). There are a lot of variables.
Be fair to those who provide services and goods to the motorcycle community before making statements. Those who provide service and support make this adventure possible.
Buy and utilize products and services with realistic expectations and learn to enjoy the ride.
Unrelated example: Millions of those ionized rubber balance bracelets, shoes that tone your butt and more products have sold and had claims both from the sellers and users stating performance and fitness gains. We all know how that worked out.
dgray5150
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