Dynomometer low cost ?

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Hm. I take it your using a redcat or clone to test? Im glad losi published gear ratios and final drive with the 5t it makes life easier lol. Im not too sure what you can do other than count teeth to find final ratio
 
Rep732 said:
Hm. I take it your using a redcat or clone to test? Im glad losi published gear ratios and final drive with the 5t it makes life easier lol. Im not too sure what you can do other than count teeth to find final ratio
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its a Rovan Baja, I marked the gears and added up the ratios ! 1 turn of rear tire = 5.7 of the pinion gear = 5.7:1
 
The smaller the gear set the higher the torque off the line. I bet if you log when the car is at say half its "speed" ill bet you get a different outcome.
 
Rep732 said:
The smaller the gear set the higher the torque off the line. I bet if you log when the car is at say half its "speed" ill bet you get a different outcome.
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the RATIO is fixed so it should not effect the torque that way , when you have gear like in a car the torque changes per gear ( 1-2-3 etc ) but so does the RPMS , Im gonna try the direct to crank first that way the gears are GONE !

I do LOCK one wheel so all the drive is to one wheel !!! ??? Maybe cut the HP in 1/2 ???? that makes sense, 6hp on this motor is believable.
 
Wait wait wait, that's the fricken problem! The locked wheel! The spiders gears take half the gearing out of the rest end when they spin. It's a 2 to 1 ratio when one wheel is stopped and the other is spinning. (Overly simplified) I'd bet money direct drive off crank your closer to the 5-6 hp mark.
Troopermaniac said:
I belive its possible to hit 7 or 8. 10 like OBR claims is funny. Probably at the crank but thats usually the area with the least load. Usually its better to measure at the rear wheels.
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The crank has the least load? You better stop building engines and go back to school mate. The engine makes the power and transmits it via the crankshaft, it sees all the load. Not some of it all of it. All the drive train does is distribute torque, set gear ratio (s) and make heat. Your truest hp and torque numbers have always been at the crank.
 
Seandonato73 said:
Wait wait wait, that's the fricken problem! The locked wheel! The spiders gears take half the gearing out of the rest end when they spin. It's a 2 to 1 ratio when one wheel is stopped and the other is spinning. (Overly simplified) I'd bet money direct drive off crank your closer to the 5-6 hp mark.

The crank has the least load? You better stop building engines and go back to school mate. The engine makes the power and transmits it via the crankshaft, it sees all the load. Not some of it all of it. All the drive train does is distribute torque, set gear ratio (s) and make heat. Your truest hp and torque numbers have always been at the crank.
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Ah worded it wrong. The crank will display the most horse power. Measuring it from there will net the best result always.

At work so trying to type fast and not thinking.
 
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Seandonato73 said:
Wait wait wait, that's the fricken problem! The locked wheel! The spiders gears take half the gearing out of the rest end when they spin. It's a 2 to 1 ratio when one wheel is stopped and the other is spinning. (Overly simplified) I'd bet money direct drive off crank your closer to the 5-6 hp mark.

The crank has the least load? You better stop building engines and go back to school mate. The engine makes the power and transmits it via the crankshaft, it sees all the load. Not some of it all of it. All the drive train does is distribute torque, set gear ratio (s) and make heat. Your truest hp and torque numbers have always been at the crank.
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Thats what I think , gonna get the crank adapter made to test it 1/2 HP is very doable power !
 
Rep732 said:
Now that looks better
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Ya I think Seandonato73 nailed it , I have one wheel locked down ! 6 HP is very doable for a 32 cc MOGEN ( Im not using motor OR engine anymore ! ) BTW this is a Race Ported ESP top end with a DDM Dom V1 pipe .

Im gonna put my stock Rovan top end and pipe on and do some runs to compare.
 
Well now I am completely baffled !! this is the ROVAN cylinder and Pipe !!! I used the piston from ESP but im pretty sure it is a stock Zenoah piston ?? .

6 HP again WTF ????

new dyno HP Rovan top _pipe .webp
 
Gearing amplifies engine torque which your dyno is set to see a twist which then your software translates to power............ if you want real numbers with no BS make an engine only dyno
 
Rep732 said:
Gearing amplifies engine torque which your dyno is set to see a twist which then your software translates to power............ if you want real numbers with no BS make an engine only dyno
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same gearing etc. ! same peak output , the curve appeares to be different but I expected a difference,, actually a big difference.
 
Kinda hard to say for me atleast. Your comparing somewhat apples to apples. Now if you took a v8 and compared it to a inline 6 with a massive turbo I can say yea big difference. These are relative to cc, stroke and the difference is in porting. Ive been reading up on harley engine mods and the one engine builder I watch keeps saying the cylinders contain the power he says power is made in the heads and cams. So if we look at 2 stroke theory the porting = more air and flow along with cams is timing and duration of the ports. So if all that changes with these engines is porting im not sure you will see a huge difference. I believe and can be wrong as I know little about 2 strokes is that the timing and duration can lead to more power along with bigger ports. But a piston only so big with no forced induction is only going to draw in so much air.
 
Rep732 said:
Kinda hard to say for me atleast. Your comparing somewhat apples to apples. Now if you took a v8 and compared it to a inline 6 with a massive turbo I can say yea big difference. These are relative to cc, stroke and the difference is in porting. Ive been reading up on harley engine mods and the one engine builder I watch keeps saying the cylinders contain the power he says power is made in the heads and cams. So if we look at 2 stroke theory the porting = more air and flow along with cams is timing and duration of the ports. So if all that changes with these engines is porting im not sure you will see a huge difference. I believe and can be wrong as I know little about 2 strokes is that the timing and duration can lead to more power along with bigger ports. But a piston only so big with no forced induction is only going to draw in so much air.
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Ya Im gonna get the direct drive adapter made to test direct off the crank and revisit this , there is one thing I did not swap over my silencer I had on with the ESP top end and V1 pipe ??? Some say they kill power so I;ll put it on this setup and test it again and see if there is a change.
 
I'd largely think the dom is hindering the power output, they arnt bad pipes, just not what dreams are made of. I would also say you'll loose a good bit of hp, with an unmodified can. This is typically a big restriction on saws, so we mod them for different things, location of the outlet pipe. Size of outlet, and how far the outlet pipe sticks inside the can effects how the engine runs. I'm truthfully surprised there wasnt much of a difference between the two top ends.
 
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