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Discussion Starter #1 (Edited)
Hi Guys,

Couldnt turn down a set of 41FCR's on Ebay UK so, I'm currently overhaulling them before looking to fit.

Any installation tips please - I've had a good look through the site and realise I might need another throttle and cables.

I almost wish I'd got split singles so I could use the malossi inlets but I can't face rebuilding the battery tray as I've installed a bigger battery, turned the starter solenoid around and am also about to fit Dyna coils, anyway I think I'll be happy with the twin FCR's if they are as good as I've been told.

Also - with them being pumper carbs, do I need to keep the fuel pump or can I get a tiny bit more fuel in the tank by removing it?

All tips appreciated

Cheers - Frank
 

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I did the 41 mm FCR's on a '96 SS/SP. At the same time I did the 944 kit, light flywheel, and a bunch of other mods. My FCR's were mounted on Malossi short intakes so the fuel became a gravity feed system. So, I was able to jettison the fuel pump. Worked well, too. I would bet that unless you put those carbs below the tank you won't be able to lose the fuel pump. Just seems logical to me. BTW, can you explain what "pumper" carbs are?
 

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Frank,

Congrats on the new carbs - you WILL definately enjoy them a lot, believe me!

If they are dual mounted you cannot loose the fuel pump as the lowest part of the tank is lower than the float bowls. If they we singles mounted on the short inlets, then you could have gained a few millilitres of fuel space in the tank by taking the pump out.

You're right, you will need new throttle and cables, don't know if you have it, but the FCR kit usually comes with an K&N filter too, but I wouldn't say it's a requirement. The carbs should have the adapters to the stock manifolds and airbox - other than that, it's just a bolt-on excersize.

Here's a link to where you can get cables and other spares for the FCRs if you can't find it in the UK:http://www.ca-cycleworks.com/shop/catalog/ducati/fuel.html
 

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You MUST use a larger float seat set.

I believe the seperate carbs come with larger seats for operation without a fuel pump.

To run YOUR FCR's without one you will need to replace the float valve needle/seat in each carb (not hard to do) with ones larger in diameter.
It WILL run without changing them, but the fuel level in the carbs will not be right, and at full throttle (after several seconds) the bowl will start to dry up and you will lose power. If you have high compression pistons it WILL start to ping as the fuel mix leans out excesively. Ask me how I know!

The instruction sheet that comes with the FCR's when you buy a kit new covers this... It has the part #'s required to do the pumpless conversion. I still have a copy, if you want I can scan and Email it to you.

ALSO:
"If you're running a ram-air setup, and using gravity feed rather than a pump to move the fuel from the tank to the carbs, you'd better route the fuel tank vent to the inside of the airbox or you'll wonder why it keeps sputtering at the end of long straights. 160 mph worth of air pressure in the float bowls and only ambient pressure in the tank will seriously slow down or even stop the fuel coming in from the tank, and the float bowls will run dry. You need to put airbox pressure into the tank to keep the fuel flow constant at various speeds."

Read more about this here: http://www.factorypro.com/tech/carbkei.html

If you do run a fuel pump and it craps out, enough fuel will gravity feed to get you home -at least it will on my bike!

If you need anymore info or want the install sheet PM me.

Good luck!,
Rich D.
 

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bruce19 said:
...BTW, can you explain what "pumper" carbs are?
They have an accelerator pump that squirt fuel into the venturi when you open the throttles.

Like your old Chevy Nova! (did you have one?) you know... pump the gas pedal twice and turn the key...

Oh BTW, ICONIC944S: You will have to do the same "trick" to start your bike in cold weather due to the fact the FCR's do not have a choke! :D
 

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RichD said:
They have an accelerator pump that squirt fuel into the venturi when you open the throttles.

Like your old Chevy Nova! (did you have one?) you know... pump the gas pedal twice and turn the key...

Oh BTW, ICONIC944S: You will have to do the same "trick" to start your bike in cold weather due to the fact the FCR's do not have a choke! :D
Actually that's what I thought. I asked because if that's true (as it is) it would have no effect on use/non-use of a fuel pump. I thought maybe there was something I didn't know about it. Didn't have a Nova but that is the way they worked on my '96 SS, of course. Thanks.
 

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Discussion Starter #8
I think the Ca-Cycleworks addition is pretty good but, does any-one know or can post a copy of the actual installation instructions please?

I can't even find any on the SUdco or Keihin websites :(

Cheers - Frank
 

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bruce19 said:
Actually that's what I thought. I asked because if that's true (as it is) it would have no effect on use/non-use of a fuel pump. I thought maybe there was something I didn't know about it. Didn't have a Nova but that is the way they worked on my '96 SS, of course. Thanks.
Yes, it's true. I have 39mm fcr's on my 86 gixxer 750. I have to do the same thing.
 

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FCR Cold starting technique

Thinking of getting some FCR41s when I get the $$$. I want them not only for the acclaimed response but also to do away with the carb icing I always get in cold weather (<40 F) with the stock Mikunis. Anyway, is there more to the cold starting trick for the FCRs than twisting the throttle twice before turning the key and hitting the starter? Do you have to stand there and continually rev the engine? How long (typically) before she will idle? Thanks-

96SP



They have an accelerator pump that squirt fuel into the venturi when you open the throttles.

Like your old Chevy Nova! (did you have one?) you know... pump the gas pedal twice and turn the key...

Oh BTW, ICONIC944S: You will have to do the same "trick" to start your bike in cold weather due to the fact the FCR's do not have a choke! :D
 

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Don't know about using them on a Ducati, but I've had them on my LeMans for nearly 10 years.

I usually have to give at least 5 squirts, and then keep the revs at 3k or so for 30 seconds (maybe longer in really cold weather), then it'll idle fine.

Some FCR41s do have chokes, though. One of the guys I work with had a Husqvarna SM that came with a race kit consisting of a lightweight full system, and an FCR41 WITH A CHOKE! I was surprised, as mine don't have them, and everyone says they don't have them, but this carb was 100% identical to mine except for the OEM choke!

Tom
 

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Here is a link to some fitting instructions. Similar came with my kit and mentions cable routing, drilling a hole in the clip-on to locate them and removing the hose from the twin boxes for the crankcase breather and plugging that hole in the airbox. You also need to trim a web between the airbox and battery tray - not all of it - just has to be enough to clear the throttle actuation thingy.

Don't forget the overflow hose like I did. I think you'd be fine without it but once the airbox is attached you'll find it very difficult. Like I did.

http://www.ca-cycleworks.com/shop/parts/FCR_install_supplement.pdf

Chris does sell a throttle and cables to suit if you have most of the other stuff and it does need to be a twin cable set-up.

Tricky bit is connecting the cables at the carb as there are 5 holes. 3 on the pull (open) cable (the bottom of the 3 is shown as being the correct one) and 2 on the push (close) cable (top is shown as the correct one). I think I may have used one different to the instructions as the cable was either too long or short and didn't work properly.

Sudco is at http://www.sudco.com/. but some of it didn't work for me today
Useful tuning guide is at http://www.factorypro.com/tech/carbkei.html

If you get stuck mention it and I'll scan the instructions I have here. Having a quiet Port or two at the moment... before bed
 

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i was lookin at the FCRs as well for my bike, are running the split singles a big advantage over the pair?
 

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I have the 41mm FCRs on my '95 SS SP and can't stress enough what a great mod these are. It's very common for these carbs to be sold on e-bay without all the necessary bits, as you've discovered in the case of the throttle and cables. The good news is that Chris Kelley at ca-cycleworks has done this a million times and he will know exactly what you need to get them working. Once popped on, I only needed to make one needle position change to find jetting nirvana. That was using Chris's jetting specs, which he supplies when you buy the carbs from him. Not all kits are created equal!

You will definitely retain your stock fuel pump. The pumper feature of the FCRs will not replace your stock pump. You will feel the pumpers kick in when you whack on the throttle too. Fun! Great response and all-around great running with these carbs. I have absolutely no complaints about them at all.

Starting: Typically two quick twists when cold, hit the starter, the bike will light off and I can gently hold the throttle (not blipping it) while it cleans out and revs even out at about 2-3k for just a short (less than a minute) bit. It will then idle happily all day long and warms up just like normal. When hot I just hit the button and it catches immediately. Remember, if you're twisting the throttle you're squirting gas down the inlets. If it's cold it'll be too much fuel and it'll flood. Let it catch and clean itself out. It'll work, trust me. It's definitely a "feel" kind of thing, but once done a couple of times you get the hang of it. I've never missed the old choke and certainly don't miss those crappy stock carbs. If you pair the FCRs with the Dyan coils you'll get nice roll-on second gear wheelies. Okay, I'm getting excited now. Time to go out for a ride. Have fun!
 

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i was lookin at the FCRs as well for my bike, are running the split singles a big advantage over the pair?
Use the separate (or "SPLIT") style ONLY if you are running the short intake manifolds. They are the only ones that will work in that application. I hear they can be harder to synchronize and keep synchronized, other than that they are the same.

And to answer the next question: The short manifolds give you more power in the 7500 to 9000RPM range. :)
 

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thx

Thanks folks for all replies! Sounds like the FCRs are the way to go. I installed the Dyna Coils recently and am very impressed with how they made starting and low-rpm running much better - plus Chris' clear instructions made the kit a very easy install. FCRs are definitely my next mod-

Cheers,
96SP
 

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FCR for dummies

If you get stuck mention it and I'll scan the instructions I have here.
I am in the process of fitting 39 FCRs to my '95 750SS - it would be great to see the ca cycleworks(..? I presume..) instructions.:) I'm having a bit of trouble with the sequence - a bit of a puzzle.

Cheers
Niels
 

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Hope these came out clear enough for you. There is a step that mentions making a 1" hole - I used the blanking plug that came with my kit and plugged the hole. This hole is below the air filter and sucks the fumes from the dead air box.
 

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I just put a set of 41s on my 93 900ss, havent got to ride it yet due to tank being at the painters but cant wait to get it put together and see how well it does, took about 10 or 15 min after reading the addvice some of these guys gave me. good luck!
 
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