How to make the FZ6R rev higher?
- Thread starter Bruno
- Start date
Thanks buddy, that is all I wanted to know...
Chevyfazer
New Member
Listen to Marty, he has fz6 cams in his bike and more mods then I think anyone else period. Even with the fz6 cams he still would not benefit from raising the rev limiter from 12.5k. Do you not feel how it starts to loose power on the top end?
If you really don't then just look at this dyno, see how the power drops after a certain point, yeah that's not going to change by upping the rev limiter
If you really don't then just look at this dyno, see how the power drops after a certain point, yeah that's not going to change by upping the rev limiter
Right now in my area you can get used SS bikes for 2 or 3 grand. I think the early 2000s YZF-R6 revved to something insane like 16k or 17k rpms. Maybe they advertised 17 but it was only 16. Only remember hearing people got pissed about it.
Anyway, probably cheaper and better to get one of those than try to mod your FZ6R to do the same. Our bikes were made this way on purpose.
Anyway, probably cheaper and better to get one of those than try to mod your FZ6R to do the same. Our bikes were made this way on purpose.
If anything just swap the motor for an r6 engine, then you get all that reving and power on a comfortable bike.
we'll let Marthy give us his explanation... he's only been in racing for forever... something about the cams, the lobes... how long the stroke is, etc.. etc. etc. (I am not an engine guy... love learning, but never needed to learn it beyond basic maintenance)
Here's my last word on the subject...
Engine design is a combo of compromise. Max rev of an engine is base on stroke. Piston mean speed need to be kept under 21 m/s or something close to that... been a while. The heart of an engine design are the cams. The cams will determine how and when your engine will produce power/torque. The comes intake runner length and diameter. Also Max RPM will set the parameter for primary exhaust pipe diameter (flow needed) and length up to the collector for best scavenging tuning at peak HP.
Now you want to spin the engine 2K RPM higher than what it was design for. Nothing is impossible... if the bottom end was design to spin 14+K You can! Here's what you need to do:
You need a complete cylinder head assembly from a FZ6 or R6 including throttle body and exhaust system. The timing chain and timing gears are different. The 6R are much smaller and won't handle the extra stress for the high rev. You need to swap to the FZ6 or R6 timing chain set up.
You could either figure out the electronics (swapping ECU or PCV fuel and ignition controller)
So those are the big lines... Can't it be done, YES! But you will end up dumping a lot of $$$ for not that much more. Well, a 2003-5 over weight R6. You can get those here under 3K these days here in the USA. That's about at least 1/2 what you will spend on your 6R.
At the end of the day, you can get more HP within the engine parameter, I did! Bone stock the bike as more power at 8K than 12K... just shift! Even with the FZ6 cams I was able to get all the juice needed under 12500 RPM (peak at 10200 RPM). I retune my bike since my last dyno run, I'll try to go and get a read on it sometime. The bike run much better now that it use to. It has incredible mid range right from 4K and pull strong all the way to 12K. Thrust me... if I could benefit from more RPM... I would make it spin faster. But I don't need to.
Engine design is a combo of compromise. Max rev of an engine is base on stroke. Piston mean speed need to be kept under 21 m/s or something close to that... been a while. The heart of an engine design are the cams. The cams will determine how and when your engine will produce power/torque. The comes intake runner length and diameter. Also Max RPM will set the parameter for primary exhaust pipe diameter (flow needed) and length up to the collector for best scavenging tuning at peak HP.
Now you want to spin the engine 2K RPM higher than what it was design for. Nothing is impossible... if the bottom end was design to spin 14+K You can! Here's what you need to do:
You need a complete cylinder head assembly from a FZ6 or R6 including throttle body and exhaust system. The timing chain and timing gears are different. The 6R are much smaller and won't handle the extra stress for the high rev. You need to swap to the FZ6 or R6 timing chain set up.
You could either figure out the electronics (swapping ECU or PCV fuel and ignition controller)
So those are the big lines... Can't it be done, YES! But you will end up dumping a lot of $$$ for not that much more. Well, a 2003-5 over weight R6. You can get those here under 3K these days here in the USA. That's about at least 1/2 what you will spend on your 6R.
At the end of the day, you can get more HP within the engine parameter, I did! Bone stock the bike as more power at 8K than 12K... just shift! Even with the FZ6 cams I was able to get all the juice needed under 12500 RPM (peak at 10200 RPM). I retune my bike since my last dyno run, I'll try to go and get a read on it sometime. The bike run much better now that it use to. It has incredible mid range right from 4K and pull strong all the way to 12K. Thrust me... if I could benefit from more RPM... I would make it spin faster. But I don't need to.
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If I were in anywhere else, I definitely would end up getting an R6... But im in Brazil, so here goes some reasons:
-R6 is not officially sold here. Some people get it throught independent importation. We do have the others SS, cbr's, zx's, srad's and R1. Though they cost over 25 grand.
-My bike was financed, and I would need to finish paying it before selling it (this will happen in 3 years).
-If I spend 1 or 2 grand for the FZ6's camshaft chain, sprocket, camshaft, ECU and etc... And get 15hp, it is great for me... The closest in price and more powerfull bike is honda cb600f hornet, which has 100hp... But this trade off would cost me 4 grand.
-And last, it would fun to see this job done!
-R6 is not officially sold here. Some people get it throught independent importation. We do have the others SS, cbr's, zx's, srad's and R1. Though they cost over 25 grand.
-My bike was financed, and I would need to finish paying it before selling it (this will happen in 3 years).
-If I spend 1 or 2 grand for the FZ6's camshaft chain, sprocket, camshaft, ECU and etc... And get 15hp, it is great for me... The closest in price and more powerfull bike is honda cb600f hornet, which has 100hp... But this trade off would cost me 4 grand.
-And last, it would fun to see this job done!
The power will drop off. My R6 will spin to 16,000 or so. My FZ6 did Rev well past 12,500. A lot has to do with the flow capability of the head.
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Now see, if you had said you were looking for more POWER in the beginning instead of HIGHER RPM's, this thread would have gone much better. Because in case it's not obvious: Higher RPM =/= Moar Power. 
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Sent from my Nexus 7 using Tapatalk 2
Cuz i've been following Marthy's camshaft swap thread for a while and also i've reading about how the camshafts work and etc. What i really had no idea about was how the the rev limiter works (And which part is responsable for command it)... So, let's say i'm not worried the engine wear, would the FZ6 ECU fit FZ6R/XJ6? Does anyone know?Now see, if you had said you were looking for more POWER in the beginning instead of HIGHER RPM's, this thread would have gone much better. Because in case it's not obvious: Higher RPM =/= Moar Power.
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No. Or maybe you could make it fit, but it's designed for a different engine with a completely different operating profile. It might fit, but the engine might not run at all and would probably run badly.
You seem to be missing what everybody here is telling you.
You CAN get more power from this engine.
You do not need to increase redline to get more power.
You seem to be fixated on revving it faster. This engine is designed to produce its best power at middle RPMs. The power can be increased, but it will still be at RPMs well below the current redline.
Stop worrying about the limitation that doesn't matter for this engine. Focus on the other things.
i can only imagine with taxes and all in brazil..... the mods you would have to do to make an fz6r rev like a super sport would cost almost as much as an r6 in the u.s....or maybe the base price of an fz6r here... from what i have been told and understand.... the fz6r in the U.S is just shy of 8k..... in brazil if i understand correctly that would be just short of 16k.....i woulda gone with the hornet to start with if i was you... its been around a while and is probably cheaper than what you got..... but you have what you have.... now you just do whats reasonable and what will make the best of it.
Just to keep you guys updated, i've just ordered the complete set of FZ6 camshafts, including sprockets, chain, chain guide, chain tensioner and etc...
Here is the link:
Eixos De Comando Fazer 600 Completo - R$ 400,00 no MercadoLivre
Here is the link:
Eixos De Comando Fazer 600 Completo - R$ 400,00 no MercadoLivre
danieljardim
New Member
You are right jon. Taxes in Brazil are absolutely insane.
Good! Read the cam thread carefully, all the info are there. And keep the whole spinning the engine faster out of the box... no need to.
Since "making more power" is the subject here. I notice through this thread about the 6R head not flowing well enough. Correct me on that if I'm wrong.
If I'm right, would porting the head help at all? I know on my truck I ported out my exhaust, intake, and valve bowls to help the head flow better. Could be way off on this one though lol
If I'm right, would porting the head help at all? I know on my truck I ported out my exhaust, intake, and valve bowls to help the head flow better. Could be way off on this one though lol
Not like it use to be back in the days. If you're driving a good old American made pick up truck... well those are still base in mid 50's technology with fuel injection added. But most high end vehicle are much better design these days, especially bike engine. With all the engine design software available and production quality thing are much better. Event back in the late 80's and early 90's I was doing Civic engine and did few test. Other than match porting... I never got any big noticeable gain. A little bit of matching around the valve seat/cylinder head and intake to head was all it needed.
From looking into the 6R it might have some improvement to make between the throttle body - rubber mount and cylinder head port. But how much would you really gain at 12K?
FastFreddy
New Member
It feels like the bottom end could easily spin up another 1500rpm. It's an R6 engine with 1-2 mm more stroke afterall.
The top end was designed to make power in a specific range though and probably wouldn't take to well to the extra revs.
You'd need to hack the ECU and put fancy valve springs in. It wouldn't make more power though without the cam change too.
It's got a high compression ratio stock, so you'd have to be an experienced engine builder with loads of spare cash to even think about it, or just buy an R6.
The top end was designed to make power in a specific range though and probably wouldn't take to well to the extra revs.
You'd need to hack the ECU and put fancy valve springs in. It wouldn't make more power though without the cam change too.
It's got a high compression ratio stock, so you'd have to be an experienced engine builder with loads of spare cash to even think about it, or just buy an R6.
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