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Discussion Starter #1 (Edited)
Hi, got some split fcr 41's off ebay for my 93 900ss but missed the malossi manifolds. Wondering if the short manifolds from one of the fi bikes might work. Does the rubber isolator match up to the fcr spigot?
Saw some 98 st2 manifolds cheap and short. Anyone ever put these carbs onto a 98 st2 or try anything like swapping manifolds from fi bikes? Can I run the stock intakes with the split singles? Thanks

 

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Hi, got some split fcr 41's off ebay for my 93 900ss but missed the malossi manifolds. Wondering if the short manifolds from one of the fi bikes might work. Does the rubber isolator match up to the fcr spigot?
Saw some 98 st2 manifolds cheap and short. Anyone ever put these carbs onto a 98 st2 or try anything like swapping manifolds from fi bikes? Can I run the stock intakes with the split singles? Thanks

Using stock intakes reduces the benefit of having split singles. The whole idea is to reduce the intake length and get rid of that big bend to get more performance. Just order the Malossi ones. If your struggling for anyone to get them off PM me and I'll give you the e-mail of a fella I know
 

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i think the throttle body inlet stub od is larger than the carb one, so the st manifolds will be too big in that sense. but check that if you can.

apart from that it's not a bad idea.
 

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Yeah, pretty sure you're going to find the EFI manifolds are too big for the FCRs. Since you saved on the carbs, just plunk down and get the Malossi manifolds and call it a day. It's a good setup that'll give you great power and response. Can't say enough good stuff about the FCRs, they transformed my SS. Good luck!
 

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Discussion Starter #5
Well I got the the carbs today and of course the velocity stack is broken on one and the inside diameter of the spigot is 39mm. Is that right? It looks like it's bigger where the slide is but should it step down to 39mm? O.D. looks like 44mm. Anyone measured their 41's and noted the I.D. at the spigot side? They have an fcr41 sticker on 'em.
http://i232.photobucket.com/albums/ee186/benrothen/DSCN2444.jpg

Thanks
 

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You'll have to cut your intakes and have them welded up. Or buy the Malossi or return the individuals and get a bank (easiest).
 

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Discussion Starter #7
I like the cut and weld approach. Will the stock isolators work? I'll be finding out soon enough I guess but maybe some one already knows. Does anyone know if the 41's should measure 39 I.D. at the spigot? Anyone have some filter adapters they want to get rid of? Maybe went to velostacks and got 'em leftover? Can you tell I'm terminally cheap? Thanks
 

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Chilehead
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OK, I've got a spare set of intake manifolds for my ST2 (new, in the box), and FCR 41s on my LeMans.

I'll try to remember to measure everything tomorrow, or over the weekend.

And take pictures.

Tom

P.S. In case I forget, someone remind me, please.
 

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Discussion Starter #9 (Edited)
Fantastic. Center to center on the mounting bolt holes to see if they are compatible with the ss flange would be helpful as well as the I.D. at thhead side would really be great. Now about those filter adapters... Oh, and still wondering on the I.D. of the 41's spigot. Thanks

Here's a shot of the st2 intakes. I'm thinkin get rid of the stock rubber that's fused on there and use some apt adaptor.

 

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Discussion Starter #10 (Edited)
Found a good reference at http://www.motorcyclecarbs.com/Keihin_FCR_Spigot_Adapter_Appl_W53.cfm

Ducati [single carb]
44.5mm OD
39mm ID



Intake Manifold Boots: Tube Type 44mm
To suit carburetors or intakes with an external fitting diameter of 44mm.
Overall length 32.9mm
Application: Dellorto PHF /PHBE
Sold individually.

Lots of info: http://www.motorcyclecarbs.com/Intake_Manifolds_C1466.cfm

Top > Carburetors and Carburetor Parts > Intake > Intake Manifolds > What to do when you cant find a Carb Holder.
Carb Holders or Intake Manifold Boots

Carb holders, (carburetors manifold boots) mount a carburetor to an engine. These holders are available in either a flange, or tube method in most cases. Details of these mounting types create some variables.

Flange Mount:
Two bolt. Used mostly on 4 stroke applications.
Four or more bolt. Used mostly on 2 stroke applications to feed reed valve cages.
Tube Mount:
Used mostly on multi cylinder 4 stroke applications.
When you need to replace an original Carb holder you may find an exact replacement unavailable. In this case maybe the following info may be found useful.

Original replacements are unavailable.
Aftermarket replacements for that application are unavailable.
So how to solve this.
Lets look at more facts:

Permanently repairing carb holders not possible.
An OD of aluminum goes into an ID of rubber.
A two bolt flange bolts to the head.
There are literally hundreds of available intake manifold boots.
Aluminum press on sleeves can be machined to change the OD of your carbs.
An aluminum flange can be made to allow a different bolt pattern to be used on your head.
Make a 1/4" thick aluminum ring Bolt the disc to the head. Mount the new manifold to the ring. This is not the best solution if you retain your stock air box as you may not be able to mount the carbs to the box.
Note that a longer intake tract promotes torque at the expence of high rpm horsepower.
Flanges of different hole spacings can be machined to be slotted so they will mount.
Your carbs if the same as another model in general maybe similar enough that the other model may only be slightly different. Then if there is a part number difference the other bikes holder may work with slight modification.
Carbs for a year newer or later if made, would work for the machine but may use different manifolds. However you could change carbs to that year.
We could put performance carbs on there that use different manifolds that ARE available.
You can usually clamp down a manifold boot 2mm too large tight enough not to leak.
You can ususally press carbs into a 2mm too small manifold boot because of the rubbers flexibility if fresh.
However it is best to provide the mounting dimensions. Specifically the OD of the carb on the engine side, and the center to center distance between the mounting bolts we may be able to find you something to work with.
 

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when i put a mikuni tm40 pumper on my dr650, i used some aluminum step rings to match up the head side and filter side. i have seen them with a slight press fit and a loose fit with jb weld. see your local machine shop for a quote.
 

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Chilehead
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ST2 manifold is 34mm at the head interface, 49mm at the TB interface, with a bolt spacing of 60mm.

Tom
 

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Discussion Starter #13
Thanks st2lemans, I'll let y'all know how it shakes out. My ebay seller already sent me another stack but am thinking of running filters.
 

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Looks like I'm giving this old thread a bump. I picked up a set of split FCR 41s. They are both downdraft carbs; not 1 downdraft and 1 horizontal as would come in the SUDCO Ducati kit. Have looked at the ST2 intakes, and they seem to be slightly curved. Malossi sells the "Ducati Intake Manifold 40mm Rear Cylinder" that seems to be short and a bit more curved than the ST2 intakes. Does anyone have any experience with getting either of these working with a DOWNDRAFT carb for the vertical cylinder? The Malossi rep said the intake fits 40 or 42mm Delortos.
 
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