ducati tuners, i need your opinion

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zap
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ducati tuners, i need your opinion

Post by zap »

:mrgreen: hi there,

because of a lack of euro's i've stopped building my paso for a while, but since a month i picked up my hobby again.

what i wanted to share with you guys is this:

http://www.mijnalbum.nl/Album=74DRR8H4

my new idea :idea: is on the last three pictures of my photoalbum:

48 MM SEMI FLATSLIDES!!! (on a 944 ss engine)

these carbs come from a honda vtr 1000 and the intake manifolds are multistrada 1000.

of course it's only mounted to the cylinder head yet, so i've still got a few problems to tackle but.... i think i can manage it.

question to you is: what do you think about the angle of these carbs?

as you can see on the pics, one carburator is in a more upright position than the other.

of course i will see it works when i'm going to test the engine, but that will still take me a year or so.

please give me your opinion,,

cheers, ab.
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Finnpaso
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Re: ducati tuners, i need your opinion

Post by Finnpaso »

I quess, that they are totally too big carburators for U 750 engine....

You have many nice things in fotos, but shall they be ever mounted to Your Paso farme such way, that it really function? If You managed, i will see result so, i wish good luck to You...
Antti http://www.youtube.com/watch?v=HeKOh3XoXPg&NR=1
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zap
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Re: ducati tuners, i need your opinion

Post by zap »

hi antti,

My paso has a 944 supersport engine and i have the st2 cams, so that helps a little to consume the huge amount of petrol.

i've done some reading on the internet and lots of tuners say that most ducati engines, when tuned, need lots more fuel.

the reason why i did not buy keihin fcr 41 flatslides is money.

these carbs costed me 120 euro, and the manifolds 50 euro.

i expect that the totalprice will be no more than 250 euro for this full working kit.

and of course i hope that it is not too much fuel for the engine.

greets, ab.
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Re: ducati tuners, i need your opinion

Post by higgy »

Ducati,making mechanics out of riders since 1946
There's no problem so bad that a little fixing can't make it worse! : )
If it ain't broke keep fixin it till it is
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JWilliam
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48mm flatslides

Post by JWilliam »

I think that if you did mount them properly in the engine the air velocity through the flatslides would be very slow at low rpm. I don't think it would like to tickover and the throttle response would be poor. A big carb for a 750.
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Re: ducati tuners, i need your opinion

Post by paso750 »

48mm carbs are too big even for a 944 engine. Intake airflow speed will be low due to the large diameter and you will probably run into problems trying to find a proper setup.
What looks weird to me too are the inlet manifolds that reduce the diameter so much. I guess the cylinderhead ports are original ?! Just combining parts w/o matching them will not work.

G.
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Brutus
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Re: ducati tuners, i need your opinion

Post by Brutus »

Ab, why not install an 900 engine with wiring..?

cheers. Léon
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Re: ducati tuners, i need your opinion

Post by higgy »

48mm carbs are too big even for a 944 engine. Intake airflow speed will be low due to the large diameter and you will probably run into problems trying to find a proper setup.
What looks weird to me too are the inlet manifolds that reduce the diameter so much. I guess the cylinderhead ports are original ?! Jus
t combining parts w/o matching them will not work.

Actually, there is away around the 48mm size and the odd shaped intake,but you would need a flow bench(easily made at home for a couple of hundred$$) or a dyno to get the shape of a restrictor plate for the intake correct,basically you would turn that odd shaped intake into a laminar flow element(LFE), and in the end the clutch will be the weak link with those big bore carbs depending on the gearing required to make such a change streetable. :twisted:As a rough estimate 50 Hours of developement time should be ALL that's required :roll: for such a UNIQUE solution 8) :mrgreen: IMNSHO
Ducati,making mechanics out of riders since 1946
There's no problem so bad that a little fixing can't make it worse! : )
If it ain't broke keep fixin it till it is
88 750
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ducinthebay
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Re: ducati tuners, i need your opinion

Post by ducinthebay »

Since these are CV carbs, they may carburate OK, but they will be a bit sluggish. Should have adequate top end, and decent mileage. it just won't have a lot of snap to it. You get the classic rubber band powerband. Its all there, but it just reacts slowly. If anything else, it will teach you to be smooth with your throttle.

Cheers,
Duc in the Bay
1990 750 Sport x2-Rosso Blanko (900ss copy) & Nuovo Nudo (Scrambler project)
1991 907 -mostly stock
2002 ST4s - Lots of mods.
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zap
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Re: ducati tuners, i need your opinion

Post by zap »

hi,

thanks for the replies all of you.

i think the best thing to do is buy a pair of keihin fcr 41 carbs.

maybe some time next year i will mont them, just to see how they run.

by then i'll let you know.

thanks, ab. :mrgreen:
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Re: ducati tuners, i need your opinion

Post by higgy »

If you need first hand info on the 41mm keihin check out this link
http://www.ducatitech.com/2v/fcr_faq.html
Ducati,making mechanics out of riders since 1946
There's no problem so bad that a little fixing can't make it worse! : )
If it ain't broke keep fixin it till it is
88 750
90 906
92 907ie
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