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I have been in contact with Ducati Kaemna in Germany which is very big on tuning Duc`s down there.The boss told me in a mail that a Keihin Flatslide kit would unleash some grunt.But its a quite pricey kit with almost 1000 Euro`s.Anyone in here have a kit like that fitted? Can you tell a BIG difference ? Should i rather go for a big bore kit (944 cc) than a set of flatslide carbs ? What about both ? 944 big bore kit and flatslide carbs ?? Experiences are welcome !!!!
 
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Well that was some really interesting reading!! Thanx alot for the link...where do i get the best price on a 41 mm kit ?? Sounded really interesting with a pair of 41 mm Fcr`s 8)
 
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I've never ridden a 900 with FCRs, but a friend I've ridden with has them on his 900SS. He told me they were a nice improvement - not so much a massive power boost as more of a crisper faster responding carb at any engine speed.

When my stock carbs require major service, they will be replaced with the flatslides.

Chris at ca-cycleworks(owner of the faq link that you read) sells the FCRs as a kit and sets them up before shipping. You will need to contact him to see if he sells outside the U.S., though.
 
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I have them and looooove them. A friend of mine has them on a 944 kit and adjusted the cam timing. His dyno run peaked at 89.1hp, pretty impressive. I am having my bike dyno tuned and have done no engine work. I will post when the run is complete.
 

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Mine are very good. Only problem is starting in really cold temps without a choke. I would do it again.
Doc
 
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I guess I need to ride a bike with the Keihin's. There must be something there that can't be easily quantified.
Last year when I was investigating building the Mrs a new bike, I was considering the Keihin's and I ran some carb flow numbers. From memory, a single 38mm carb (stock) had nearly twice the flow capacity required for a 900 at 8000 RPM. Once I ran the numbers, it was going to be hard to part with the one large for that purpose.
That being said, every owner that I've heard comment has had nothing but praise, good dyno numbers, and minor cold start issues. I guess flow numbers don't tell the whole story.
 
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I have 41s on my bike. They're great little pieces of hardware, and add a nice "crispness" to the whole package. Personally, it would be tough for me to justify the cost of the FCRs if they were just gonna sit on the long manifolds.
http://meccanicacorse.net/gallery/Dyno-Charts/manifolds

I'd like to ride a bike with Doug Lofgren's taper-bored carbs. It sounds like a cost-effective alternative to FCRs, but I have no FHE.

I guess it's all in what you're looking for. FCRs are cool. But for the money you could get decent head work and a Nichols flywheel. Or maybe lighter rods and a light flywheel. Or an expensive hooker. Lotsa options.
 

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Hi Tim,

unfortunately, your post isn't right. there are some things to realize. first of all, anything can be proven on a dyno that the dyno operator wants to prove. next, simply throwing parts at an engine is never the answer.

"anyone" can get up to 85 or so HP out of the 2V engine by throwing parts at it. of all the parts one does to "throw at" the package, the FCRs on the long manifolds are the most effective. this yields great throttle response and does things for the power delivery that are unbelievable until felt. these things you cannot get with the CV carbs (even with modifications).

one of my customers was able to coax 80 hp out of his almost all stock 900ss. the engine had never been opened. it has ignition mods, special tri-core mufflers, and serious carb tweaking over many dyno runs. we slapped the FCRs on his bike and the first thing he said was "why didn't you tell me to do this 2 years ago!?". well, i did. ::) he said it was far more powerful and wheelied easier. first dyno run showed a 6hp loss from before. as we later figured out, his bike is something "Special" and required some tuning to get right. different slow jets and some tweaks on the mains and he's up to 82 and happier than ever.

now, on to the topic of the short intake manifolds. this makes life a little more difficult. first, you need to take sawzall tothe cross frame member in the engine bay. then you buy manifolds, rubbers, "carb kit", filter adaptors, and filters. so you're like $1400 spent. you put them on, go spend hours on the dyno... and get... 82hp.

then you put in big valves and "do port work". then you get. 85 hp.

you need to do full-on serious Guy Martin "testa-rosso" headwork. the shape of the ports is carefully changed and everything is considered in the process while only using the best parts. problem is, this package is aserious investment on top of that $1400 investment. but this is what's required to get the power.

in january, i will have pongo done and build a webpage detailing the benefits and downfalls to what i call "the arms race". there is good argument for starting with the maximum available weaponry, rather than attempt incremental approach to your development. the key issue is that the customer needs to evaulate where they want to end up in this "arms race". if they want to go all the way, then this is the package.

i'm going to call it the "weapon of mass destruction" package. it's all out warfare on the horsepower front. unfortunately, to get this power means a serious one time committment of money. but in overall terms, it's going to result in less money spent and more horsepower at the pavement than any other 2V option.

:) chris
 

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i was looking for this picture to add in the above post, but couldn't find it. then Power Point nuked on me and i had to figure that out.

anyhow, notice the flow results. this is what's important with porting. most folks (myself included) that do porting are all doing cursory observable changes to the metal where the air flows. this is typical shadetree type of stuff. and it will have some affect to the power, even with big valves that have bored pockets that are blended to the seats (and whatever other coolio preformance oriented catch phrases you want to use). but that's all worthless without a flow bench to measure the changes.

notice how the stock intake ports basically stop working at .300" of lift. that's the problem of the 2V engine. that is why you so often see 900s making something near 85 hp, but not much more. the intake port tapering off flow is the brick wall that people hit.

now, you see my avatar? with 900 or ST2 cams, you get about .460" of lift. in the fixture Guy Martin uses with his flowbench, he doesn't have cams or rockers. that's how he's able to lift the valve another .100" past the cam's ability to lift the valve. his head work produces HUGE gains in flow from .200" to .500" of lift, where the cams work. as you can see, he is essentially "adding" .100" of lift to the cams worth of flow with his work.

i am hugely anticipating the completion of the project. ;D
 
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unfortunately, your post isn't right. there are some things to realize. first of all, anything can be proven on a dyno that the dyno operator wants to prove. next, simply throwing parts at an engine is never the answer.
Hmmm. Perhaps I misrepresented myself. I don't advocate "throwing parts." All of my projects have a set of goals, a budget and a talented builder. All I meant to suggest was that, depending on a person's particular goals, the cost of FCRs might be better spent on other things. Is that really wrong?
 

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Buy from Chris, I can't stress this enough. I bought mine through someone else and I didn't get anything I needed.
Chris sells as a kit, and its at a damn good price too. I can not recommend him enough. He has helped me piece together the missing pieces I have needed for my FCR's and I ended up spending about 120 bucks more because I thought I was getting a "deal" from somebody else. Plus Chris has tons of know how and has done this stuff before.

I got my FCR's on today, and am awaiting the air box adapters from chris, I still started her up in the garage with the new sils and FCR's and ahhh, I'm so excited.

-Patrick
 

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Discussion Starter #15
there simply ain't any reason not to buy them from Chris!
Well,if there is no choke....there you have a reason! Hehe! I live in Norway and some times it can be really cold and moist here and i cant see how to get my Monster started without any choke lever to pull.........is there a possibility to mount a choke system on them ?? Or have i misunderstood.....there is choke on those FCR`s ??
 

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hey y'all, thanks for the praise. :)

hey Norway, if you regularly ride when the air temp is BELOW 40 deg F ( or roughly 4 deg C ), then yes the lack of choke will be a little troublesome.

When I was in college, I used my Ducati 900SS with FCRs as my commuter. Here in San Diego, the air temps are regularly between 40 and 45 deg F in the winter in the mornings. Some days cooler, but I really do not like to ride when it's under 45 deg F and REALLY don't like it under 40 deg F, so my experience is limited to air temps warmer than those.

The FCRs do not have choke, but they do have a long tether on the idle speed screw that you can zip tie to the frame where it can be reached while seated on the bike. When you "know" it is cold out and the bile will be unhappy, turn the idle up a few turns. Then twist throttle once or twice. Start engine. No problems. Aiding this is having the idle and low speed circuit jetting towards the rich side as opposed to the lean side. I did this for a couple years with no problems. Once you get the procedure, choke isn't needed.

:) Chris
 

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Discussion Starter #17
Thanx for the tips Chris!! I guess you get used to not having a choke option on your bike.And about hp/torque with Fcr`s......response is something thats not so easy to "measure" if y`all know what i mean.Cuz it all sounds like engine response is one of many good things with the Fcr`s.I really drool after Fcr`s now [smiley=applause.gif] [smiley=applause.gif]
 
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no you don't want no stinkin' fcr's... they'll only make you happy... who wants to be happy... nobody... that's why you don't need no stinkin' flatslides. ;D





if you read any further the secret is fcr's = good, you won't ever look back.

if you're worried about the choke for cold starts install the dyna coils and ngk wires kit that chris sells also. just blip the throttle twice and press the starter. a little wrist action will warm it up just fine. the extra spark will fire 'em up easy enough and really smooth out the low rpm bogs.

i've got a 900ss with hi comp pistons, 41fcr's, dyna coils, nichols flywheel, nichols clutch basket... all purchased from mr. kelley. it runs like a champ. it makes me happy. ;D
 

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Discussion Starter #19
Guess i have to spend some $$$ on a coil kit too.......i have been thinking of ordering the Ducati Performance cdi units. Do these match up nice with a pair of Fcr`s,Dyna coils and a light flywheel ?? Or are those cdi units just a waste of $$??
 
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