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Short rod motor esr 310 with trx9 port match and trx9b pipe,38 a/s, esr reeds, race dome we lost the one where it made 49.86 the rest are right at 48 is that about right and what does everyone think about the curve
63795
 

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Nice, I would love to put my R on the dyno. I just don't have the time as I work around 3000 hours a year....
 

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Eddie hand ported your cylinder?
 

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Good numbers. My esr 310 with a very rich tune on the ocp dyno made 52hp. That's with nate McCoy drag porting.
 

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bdt261. badd ass. posted here. 57hp-40tq



i have the best. bdt built engines.
bdt261 oem
bdt363 prox
bdt431 puma
bdt561 saber
Sent from my iPhone using Tapatalk
 

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bdt261. badd ass. posted here. 57hp-40tq



i have the best. bdt built engines.
bdt261 oem
bdt363 prox
bdt431 puma
bdt561 saber
Sent from my iPhone using Tapatalk
I don't care to or really like to post Dyno sheets, it always causes an uproar. With that said; Nice Dyno run Korldickens...!

Only takes <1 hours to get 3 pulls on a Dyno...everyone should go to a local Dyno shop and get Three pulls in, don't need to share the results, it's just a "got to know" piece.

IMO the most impressive part of the BDT261CC MX-TT series of OEM engines are the Torque they put out; 40.49lbs. While 57HP is a boat load of HP, it out performs any 310CC, most 330CC's and some =>350CC's on the Torque output...you will not see that on other Builders OEM 261CC engines.

As has been the BDT tradition for years, anyone is welcome to schedule a visit to BDT, when visitng the Dunes (or another occasion) and run their setup on the BDT Dyno.

Carlos
 

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Good numbers. My esr 310 with a very rich tune on the ocp dyno made 52hp. That's with nate McCoy drag porting.
Is that the 310 you had when we raced at Winchester bay?
 

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Discussion Starter #12
I don't care to or really like to post Dyno sheets, it always causes an uproar. With that said; Nice Dyno run Korldickens...!

Only takes <1 hours to get 3 pulls on a Dyno...everyone should go to a local Dyno shop and get Three pulls in, don't need to share the results, it's just a "got to know" piece.

IMO the most impressive part of the BDT261CC MX-TT series of OEM engines are the Torque they put out; 40.49lbs. While 57HP is a boat load of HP, it out performs any 310CC, most 330CC's and some =>350CC's on the Torque output...you will not see that on other Builders OEM 261CC engines.

As has been the BDT tradition for years, anyone is welcome to schedule a visit to BDT, when visitng the Dunes (or another occasion) and run their setup on the BDT Dyno.

Carlos
Your not kidding about the uproar I posted one on Facebook... not a real good idea and I wasn’t real concerned about peak number I wanted to see how the curve looked and I’m very happy with it for the price also the mechanic sent the other runs where it made 49.84 with that being said I have never taken anything to the dyno so it was fun and I got to see some things that I don’t normally get to see
 

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Is that the 310 you had when we raced at Winchester bay?
Yes. On the dyno I had oem I believe. Wish I had it dyno'ed with cr ignition. It's seized up now and tore apart. Eventually it'll go to Pete's for a rebuild and maybe a few of his tricks.
 

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I don't care to or really like to post Dyno sheets, it always causes an uproar. With that said; Nice Dyno run Korldickens...!

Only takes <1 hours to get 3 pulls on a Dyno...everyone should go to a local Dyno shop and get Three pulls in, don't need to share the results, it's just a "got to know" piece.

IMO the most impressive part of the BDT261CC MX-TT series of OEM engines are the Torque they put out; 40.49lbs. While 57HP is a boat load of HP, it out performs any 310CC, most 330CC's and some =>350CC's on the Torque output...you will not see that on other Builders OEM 261CC engines.

As has been the BDT tradition for years, anyone is welcome to schedule a visit to BDT, when visitng the Dunes (or another occasion) and run their setup on the BDT Dyno.

Carlos
Carlos,
Matuus's 261 with 57hp at 7.5K is very impressive.
I'm sure you can make my 1983 CR250R 68mm short rod 261 engine capable of 50 plus hp with your wurks pipe, cylinder and head work.
My 38mm Mikuni SBN carb and PVL analog ignition will finish it off nicely.
I can build , setup and tune my specific piece of machinery but I need your expertise in Cylinder/head/pipe modification engineering.

I had doubts about sticking with a 261 short rod engine but I've been impressed with many examples how well they perform.:)
 

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Carlos,
Matuus's 261 with 57hp at 7.5K is very impressive.
I'm sure you can make my 1983 CR250R 68mm short rod 261 engine capable of 50 plus hp with your wurks pipe, cylinder and head work.
My 38mm Mikuni SBN carb and PVL analog ignition will finish it off nicely.
I can build , setup and tune my specific piece of machinery but I need your expertise in Cylinder/head/pipe modification engineering.

I had doubts about sticking with a 261 short rod engine but I've been impressed with many examples how well they perform.:)
I think short rod is the way to go for your HotSaw; a more exotic builds yielding more power on your saw would be a de-stroked crankshaft to say 69MM and run a 69MM bore....square bore/stroke engine HotSaw :)

Carlos
 

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I think short rod is the way to go for your HotSaw; a more exotic builds yielding more power on your saw would be a de-stroked crankshaft to say 69MM and run a 69MM bore....square bore/stroke engine HotSaw :)

Carlos
Thanks I never thought of destroking the crank and a square build is good.
I looked into installing a 69mm Wiseco 526 series piston but the older 446 in my '83 is 3.2mm taller from the pin's center. Both pistons are otherwise the same height.
If I combined lowering the cylinder base and crankcase deck 3.2mm and take that much again off the cylinder deck it would work.
The ring stops are 4mm closer together on the 526 piston but from what I can see there would be no danger of a ring snagging the main intake boost port.
69mmx72mm =269cc
 

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Don't worry much about ring ends snagging ports, or intake boost port. You would be surprised how insignificant that concern really is in the real world.

Carlos
 

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I think short rod is the way to go for your HotSaw; a more exotic builds yielding more power on your saw would be a de-stroked crankshaft to say 69MM and run a 69MM bore....square bore/stroke engine HotSaw :)

Carlos
No that won't work Carlos. I just put my thinking cap on, hehe.
I would have to stroke my crank 3mm to 75mm to run the 69mm TRX piston in my '83 CR250R.
The Wiseco 526 series piston's pin is 3 mm closer to the crown edge then on the '83 446 series piston.
The 526 is 38 mm pin center to crown edge. The 446 is 41.2mm
Both pistons are still the same overall height though.
That's how Honda lowered the cr250 cylinder in 1984.
So even though both engines have the same 72mm stroke 125.50mm connecting rod. My 1983 has a 3 mm longer cylinder wall for a power stroke.
Might be the reason why some people say the 1983 CR250R sounds like a CR500.
So my question is would that 3mm longer power stroke be an advantage?
 

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Korldickens, sorry for derailing your thread again.
Carlos,
If I put a 130.50mm long rod in my 1983 125.50mm short rod motor which has 1.50mm piston edge below deck. The piston would be 3.50mm above deck.
If I put a TRX piston in my motor on the long rod the piston would only be 0.30mm above deck on the '83 motor. Reason is the TRX piston pin is 3.20mm higher towards the crown edge.

41.20mm 1983 pin center to edge
-38.00mm TRX pin center to edge.
=3.20mm
Both pistons are identical in height.

So a standard .020" base gasket 0.30mm thicker (0.032")would bring the piston to zero.;)
 
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