I have a 1990 CBR1000F and I am having a hard time finding an aftermarket manifold for a fairly reasonable price, everywhere I have looked I am in the realm of spending anywhere from $800-$1000 alone on a manifold, if anyone knows where I could save some $$$$ on even a new one in good shape would help tremendously. I want something that is efficient with the exhaust flow, even one that is set up for straight pipe, as I have a machinist who can manufacture a restrictor plate for the carbs if need be as I have stock carbs, air box, and cams.

 

I bought my 1990 with a delkevic exhaust system, which looks like it came as a complete set with a 4 into 2 manifold. Can't swear to it, but check what they currently offer.

 

Keep the factory one, plug one side and add a free flow slipon.

Welcome to the forum.

 

I currently have a stock manifold and exhaust on the motorcycle, but I have decided to pull the exhaust off due to the fact that whoever had the bike previous to me drilled about 10 holes or so in the exhaust which completely defeated the purpos o an exhaust o provide back pressure an also silence end exhaust noise. With that being said I would love to go back to stock because I know the system would have worked just fine as is. Even with that where the manifold
clamps the stock exhaust is completely rusted out and is not useable unless I want to straight pipe the motorcycle. I have bought a complete Pro Jetting kit from Dynojet, which gives me everything I need from Stage 1 to Stage 5 but with no exhaust at all I am looking at getting either flat slide carbs (which I have had no luck of finding for this bike) or running a restrictor plate in front of the carbs even with jetting. I want this motorcycle to run with prime rideablity and also maximum performance. So I want a medium between the two but can't rationalize spending as much as $800 on an exhaust unless I am going to go all out flat slide carbs with over sized valves and a bigger cam. When it comes down to it I just want a fast reliable street bike. I am just having a hard time finding stock OEM Honda parts that I would feel comfortable buying and could justify buying as I am a college student who loves fast motorcycles but can only afford so much. I have access to machine shops though many of the people I ride with and also my Father as he is a speed demon himself who has expierenced everything from the fastest drag bikes to a comfortable Cruzer. But even he has had a hard time finding the stock parts I desire. I am truly all for restoring a bike to its original beauty as that I where I see the most value. So I am looking for suggestions as to where I can find stock factory OEM parts for this beautiful revelutionary bike of its time. And the key is good quality but quality that will be there at any given time so I can purchase when finances allow. So if anyone has spare parts for a cbr1000f stock or aftermarket for a good price an in good shape please private message me and possibly we could work out a deal. For I am on a budget but want quality with paying an over rated price.

 

Also thanks for welcoming me I love to hear what people have going on so maybe I can help as I have gone to school for building race engines for motorcycles. But have not acquired the resources as far as people to help me with finding parts.

 

In the 8 years that I've owned my bike, an '87 MkI, I've considered everything that could be done to increase performance and finally came to the conclusion that it's just fine the way it is. The dearth of aftermarket goodies for my year is a strongly determining factor, but after putting miles and miles on it in just about every condition of road and weather it always gave me what I wanted from it. I'm satisfied.
The only mods I've done are the stick coil and a K&N filter.

Some people here have re-jetted. They can give you advice on that.

Big valves? Big cams? Flat slides? Good luck on that. Keep in mind though you might be destroying the main thing these bikes are known for and that is their reliability.

Also, keep in mind that in your need for speed, you should consider safety. Fast bike is no good to you if you can't stop. Brake rebuild, braided lines and such are easy cost effective things that will pay dividends while you look for more power. On a near 30 year old bike, it should be done anyway.

The stock 4-1-2 exhaust system was, in my opinion, designed to provide the most mid range power.

 

I agree, drilling the stock cans would sound like a leaking system.

Have you looked into Delkevic silencers <LINK>? £250 would be about $325.00 +shipping.

 

That is very similar to my exhaust system, although my mufflers are the 230mm which need some extra fibreglass to quieten them down for road use. the 450mm should be fine. Nice looking exhausts, which fit well.