And hereis abefore pic showing that the ports are veryunsmooth stock.The engine will also recieve new cams to improve mid and top range, and an Akrapovic unrestricted 4-2-1 system. In case it pulls well enough up to 200 km/h, i.e. the concept works OK, it will also be provided with RAM air to handle wind resistance at higher speeds. It is possible to use the air ducts from newer FI-models and gaing another 5 to 10 hp at high speeds. That mod requires to put the float chambers under pressure from the air box, and possibly also an electrical and regulated fuel pump.

[IMG]local://upfiles/4562/5F3C1AF0891D44FCA97815A05C5FDF74.jpg[/IMG]

 

my cbr1000f has its head cleaned out n machined exhaust ports by a previous owner,i have not long fitted larger bore stainless downpipes and end cans(i like twin cans) and its made an amazing difference to the power,it always felt like it had a cold b4,obviously the carbs need a sort as well but just minor adjustments.
only problem i have now is the fairing lowers wont close up and i get the occasional melting plastic smell.
so if u can afford it,definatly an improvement for little money and quite a buzz munching the newer bikes out there with a bike that looks standard /original

 

I had the same problem with mine and the fairing ended up having a hole melted in it.

But you can get mats that the use to wrap turbo's etc and just glue them to the inside of the fairing.

 

Finally, I got the chance todayto test theBird with the ported head and other camshafts. I only runned for about 15 minutes before I returned and changed oil. The initial impression is that I have got a completely new bike, the throttle response is far better and when I launched like usual the bike did a long wheelie which it have never done during the same conditions. Will test more the coming weekend but there is no doubt that the porting and other camshafts have done great things to the engine.

 

Sounds Great! Are you gonna dyno it? Would be interesting to hear what the porting by Dr: Bike alone did for power without the other camshafts.

 

Do the heads need improvement?

From automotive experience on automotive engines, if you just port the heads you will do nothing and will probably not run good. Change one thing, everything else has to support that mod. Port your heads then you need: Higher Flowing Carb, Intake, Exhaust, Camshaft for those components, and the powerband will probably shift to higher RPMs.

But hey, if the heads are the only bottle neck, porting will improve guarenteed.

Its just like the K&N filter, by installing, people unconciously think it increases valve lift, ports out your intake runners while increasing compression. LOL

 

You are right, just porting doesn't mean a terribly lot unless other things are done. But, the cylinder head on bikes from the 90's have a lot of imperfections stock since they have old type angled runners and are just raw and unprepared castings form the production line. A so-called street porting will remove production flaws, smooth the short side radious, and line up runners and valve seats. On top of that, a Mira cutting an unshrouding of valves will improve flow, especially the low lift flow. All those small but quite noticeable things will add about 10 hp on a 1000 CC engine. When the complete system is matched with other cams, more compression and lower squish height, a free flowing tuned exhaust system and opening the intake, the performance increase will be substantial. In the region of 25 to 30 rwhp on a 1000 CC engine. What is equally important is to keep or improve the midrange response, which is used at exists. That means the runners can’t be drag race type for maximum power only.

 

Yes the bike will be dynoed. I have just opened the fuel screws half a turn and shimmed up the needles by a M3 flat bracket to be safe. The main jets will only be needed to the full capacity at max rpm on high gears, so the bike can be used as is until dynoed. The power will increases the appetite for fuel, but the raised compression, from 11 to a little more than 12 to 1, and the reduced squish height, results in less fuel consumption for a given power figure. So, the end result is that I have no idea and the engine must be benched. I don’t know what the porting itself is doing, I guess about 10 hp since the flow, leaving everything unchanged, will be about 15 % more flow for a well done street porting, and Dr. Bike has done a true artwork with the runners and combustion chambers

 

is this something your doing? or just thinking of doing?

 

It is all done, but the bike is not dynoed yet. Thefeeling in thebackreports good things have happenedto the engine though. It is by fareasier to feel performance increase on a bike than a car. The amount of front lift and how easy that come or not gives good indications of the power level and delivery. Also if the rear wheel spins or the bike grips and leaves ground easily tells a lot about how the torque band is. To late and intense power will cause lost grip in the rear, if the power builds early and evenly the weight is better transferred to the rear and the bike is much easier to control..