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What causes the shorty to be different/better? And is it better for the ATC as well?

I have no issues with my standard 38 PWK, just asking to learn something.
Soon enough, BDT will have a SB (Short Body) version for the ATC250R in 38, 39, 40 and 41.5MM. Currently in process, will sell for the same cost as the TRX250R SB versions. And be in stock & available only through BDT Motorsports.

I will post availability in the next 5-7 weeks.

Carlos
 

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Carlos what cable do you recommend for the 38mm short body? It would be for a stock oem thumb throttle. The one Eddie has is to short if I remember right. Do you have correct ones in stock at bdt?
 

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Carlos what cable do you recommend for the 38mm short body? It would be for a stock oem thumb throttle. The one Eddie has is to short if I remember right. Do you have correct ones in stock at bdt?
BDT has longer MP cables in stock. They are a much higher cost cable since anything you order from MP (Motion Pro) that is not a standard P/N & Length, is process as custom, and charged a premium price.

Carlos
 

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Discussion Starter #24
BDT has longer MP cables in stock. They are a much higher cost cable since anything you order from MP (Motion Pro) that is not a standard P/N & Length, is process as custom, and charged a premium price.

Carlos
Does that +2 or 3 come in clear stainless braided 😛. I would be interested. My MP is tight and I want a taller stem.
 

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I’m currently running a 40mm Lectron and it rips. It’s not a BB motor though and I will admit that it definitely took some time to dial in but when I finally got it, I felt it was definitely worth keeping. It has a bit of a different feel in the power vs. an Airstryker but I like it because elevation changes seem to not have as much affect on it and when it does u just adjust the needle -I went from riding in NM (~7k ft. elevation) to St. Anthony’s ID and it only needed minor adjustments. It definitely gives it more top end though and that’s why I like it, it revs to the moon. I even have a tapered bore Keihin carb that I was excited to try because I think it may be a Selvy Sonic carb, and I still prefer the Lectron over that beauty because I just got used to it I guess.
 

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i ride @ sea level n up 6000’. same jetting. pwk. as. sb carbs. oem n bb engines. carbs all setup by bdt. all rip.


i have the best. bdt built engines.
bdt261 oem
bdt363 prox
bdt391 ceo
bdt431 puma

Sent from my iPhone using Tapatalk
 

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It definitely gives it more top end though and that’s why I like it, it revs to the moon.
I’m interested in this statement. I have a standard bore ported cylinder and a 38 PWK. It revs out great but I am always looking for more RPM. What is the concept/idea that a 40 Lectron will produce noticeably more RPM?
 

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I’m currently running a 40mm Lectron and it rips. It’s not a BB motor though and I will admit that it definitely took some time to dial in but when I finally got it, I felt it was definitely worth keeping. It has a bit of a different feel in the power vs. an Airstryker but I like it because elevation changes seem to not have as much affect on it and when it does u just adjust the needle -I went from riding in NM (~7k ft. elevation) to St. Anthony’s ID and it only needed minor adjustments. It definitely gives it more top end though and that’s why I like it, it revs to the moon. I even have a tapered bore Keihin carb that I was excited to try because I think it may be a Selvy Sonic carb, and I still prefer the Lectron over that beauty because I just got used to it I guess.
i ride @ sea level n up 6000’. same jetting. pwk. as. sb carbs. oem n bb engines. carbs all setup by bdt. all rip.


i have the best. bdt built engines.
bdt261 oem
bdt363 prox
bdt391 ceo
bdt431 puma

Sent from my iPhone using Tapatalk
I’m interested in this statement. I have a standard bore ported cylinder and a 38 PWK. It revs out great but I am always looking for more RPM. What is the concept/idea that a 40 Lectron will produce noticeably more RPM?
Nothing wrong with Lectron's as I have always stated, just not a common carburetor for most to tune or get parts easily. Main reason I always recommend Kehein's is the parts; jets, needles, slides available locally at any motorcycle shop. BDT stocks & sells all 3 Carburetors & Parts; Lectron, Mikuni and Kehein.

As far a one carburetor "gives it more top end" than others, it's a direct function of air & fuel flow. Test equal carburetors of the same size (38 vs 38 or 41 vs 41...tapered vs tapered), jetted properly and the HP & TrQ output will be the same as long as both are moving fuel & air atomized into the engine at the same amount.

On the BDT dyno and validated on the Track, you do see a few equal characteristics across the spectrum of brands;

Smaller bore carburetors favor low end TrQ, quicker low to mid response
Larger bore carburetors favor top end HP and lower low to mid response
Short Body (SB) carburetors (regardless of brand) offer much quicker response low to mid than equal sized standard carburetors
Flat Slides favor mid to top end power
Round or oval slides favor low to mid power

Another important point to consider; healthy engines (no leaks, great bottom & top ends, ect...) are the easiest to tune and maintain their state of tune. 250R BDT Racers hardly ever, really never chase jetting, regardless of carburetor manufacture. Once a "healthy" engine is properly jetted & tuned, it pretty much stays that way regardless of temperature or altitude changes (all within reason; 50-90F, Sea Level to 5000'). I know this is hard for some to believe, however; it's absolutely true...!

BDT has customers that swear a Mikuni is the "best", other customers the Lectron, and the rest think their Kehein is all that. All about what works best for you, and what you'er the most comfortable tuning & running with.

Carlos
 

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I’ve never dynoed it or anything like that so it was more tried and true testing like drag racing or when climbing hills at the dunes, I can pull more gears and still have the power to climb. Stuff like that. It’s just different, a little hard to explain but I’m sure you get the point. I still have my Keihin carbs but I like the ride-ability of the power that the Lectron delivers. Hope that makes sense, lol
 
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