45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

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agertz1
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45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by agertz1 »

I would use oem. inj. but not readily available, used. How much headache am I getting into ? Simple IR. manifold. I was considering starting at 8",ram tuning length, vs. stock about 3" ? I can easily shorten tubes as needed,(rubber spigot mounting on head. Pump gas, stock motor but 300+ lbs, more load.
Thanks, Art.
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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by Nut124 »

Seems like a lot of carb for a small engine.

What kind of HP are you planning on making? Dual 45s are good for over 200HP.
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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by Caprimaniac »

40’s should do. But 45’s with a smakl venturi, 32-36mm? Might work well.
I thought the bandit had a twin? So 1 carb would do both.

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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by agertz1 »

Stock hp. is 96. Leaving stock except for possibly these DCOE's. Stock TB's are 36 mm.
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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by PackardV8 »

Having BTDTNA may years ago, by the time one finds and fettles the carbs, fabricates the intake, air filter, throttle linkage, fuel lines and spent dyno time on the tune, he'll most likely wish he'd have spent less time and money on the OEM EFI.
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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by frnkeore »

40 DCOE's is all that you need.They will do 160 HP, with ease, with 35mm chokes but, if you can get 45's cheaper, they will work find with 35mm chokes, too.

You will need to tune them on a dyno though but, after tuned, they are much simpler than any FI and only need a low pressure fuel pump and a single fuel line.
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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by BCjohnny »

40s would be all you'd need, with the correct chokes

Be wary of putting 45s on and choking them waay down ...... remember the 80% rule of thumb

I still think set up would be a pain even with accepted base parameters ....... you'll have the looks but quite possibly a whole load of rideability issues without interminable tuning ...... FI would make more sense

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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by Nut124 »

agertz1 wrote: Thu Jan 07, 2021 11:30 am Stock hp. is 96. Leaving stock except for possibly these DCOE's. Stock TB's are 36 mm.
What is the orientation of your engine? DCOEs are designed for to bbls to line up in direction of the road. Mounting them sideways results in lean/rich under cornering.
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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by wombat58 »

Why not source some proper motorcycle carbs, like Mikuni RS38's? Will outflow the DCOE's, and you don't have to fabricate an oddball manifold.
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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by agertz1 »

Good news is I found the oem injection set up. Thanks, Art.
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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by naukkis79 »

agertz1 wrote: Thu Jan 07, 2021 11:30 am Stock hp. is 96. Leaving stock except for possibly these DCOE's. Stock TB's are 36 mm.
Stock power is limited by secondary butterflies, they won't open fully. Just with removal of secondaries or programming them to open fully brings power to ~120hp or so.
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Re: 45 DCOE's (2) for 1250cc Suzuki Bandit, 4 cyl, 4 cycle

Post by Truckedup »

From my experience flatslide bike carbs are more tolerant in bigger sizes than butterfly throttle carbs.
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