Raptor Composite Aircraft

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Deuelly

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Nov 6, 2012
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201
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Marshall, MN
Thoughts on the belt. On a supercharger setup one pulley can have a flange to keep the belt centered but if the shafts are parallel to one another you can have no flanges and the belt will stay centered. On a supercharger setup the belts are kinda loose when cold due to allowance for thermal expansion of the engine. I wonder if he has any allowance in the tightness for thermal expansion?
The shaft alignment is variable via engine torque. It a real ingenious design. :D:(
 

TarDevil

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Jun 29, 2010
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Coastal North Carolina/USA
The shaft alignment is variable via engine torque. It a real ingenious design. :D:(
He now admits it, and apparently considers it acceptable.

Peter:

Yep. It likely tracked off because of deceleration on the last run. Under load it tracks one direction and when backing off it tracks the other, if only slightly.
 

Scheny

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Feb 26, 2019
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201
Location
Vienna, Austria
I was following the blog of a german biker who wanted to transform his bike from chain to belt back when only Harley used one on a single bike. German authorities are very strict about road approval and they refused to give him one, as the belt was way below the required torque.

In the end he got an approval, as he showed the agency that it is under dimensioned by the same factor, that a common chain would also be in any road legal bike. He also showed that the arm kinematic of the Harley was in violation to the belt manufacturers requirements, as it loosened under compression.

According to the specs it shouldn't have worked, but with good engineering behind it was.
 

TFF

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Apr 28, 2010
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Memphis, TN
From placement of his probe he is measuring turbine inlet temperature not exhaust gas temperature.
 

thjakits

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Jul 3, 2014
Messages
58
Location
Panama, Rep. of Panama
From the comments I read here - it seems our Raptor-builder is building a Dinosaur - ....the Asteroid just didn't hit yet....

Flexing Compressor mounts, EGT-numbers corrected by "Fantasy Physics", Aerodynamic controls with "liberal" tolerances, comoponents tested to LESS than spec, ...NO willing test pilots, test pilots suggestions/critique that did have look dutifully ignored...

Looks like another "Awesome - too good to be true - will - was - gone...." in the making.....

thjakits
 

pictsidhe

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Jul 15, 2014
Messages
7,426
Location
North Carolina
I was following the blog of a german biker who wanted to transform his bike from chain to belt back when only Harley used one on a single bike. German authorities are very strict about road approval and they refused to give him one, as the belt was way below the required torque.

In the end he got an approval, as he showed the agency that it is under dimensioned by the same factor, that a common chain would also be in any road legal bike. He also showed that the arm kinematic of the Harley was in violation to the belt manufacturers requirements, as it loosened under compression.

According to the specs it shouldn't have worked, but with good engineering behind it was.
I discovered that 25 years ago when I was tasked with selectinging an upgraded chain for a 240hp drag bike. Chains are generally sized for wear, and road bikes use their max torque capacity for very little time. max chain load is full throttle in 1st gear, even small bikes don't spend long doing that... A belt needs to keep it's slack side taught or the belt rides up on the teeth and dies, so it is a bit trickier to overload without exceeding a sane static tension. Tension is usually the design limit for belts, they don't have the reserves that chains do. Sprung idlers on both sides to cope with deceleration is how I'd do it.
 

flyboy2160

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Joined
May 25, 2014
Messages
332
Location
california, USA
More stuff you can use for The Raptor Bulemia diet: he "doesn't have time" to install a temp probe in a single exhaust pipe, but he has time to make a new custom fitting for...................................the all important, flight critical air conditioning.

What a joke.
 

pictsidhe

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Jul 15, 2014
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North Carolina
Or to even crudely measure horsepower, which would verify a lot more than actual horsepower...
It's as if he has something to hide?
 

Jay Kempf

Curmudgeon in Training (CIT)
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Apr 13, 2009
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Warren, VT USA
A belt needs to keep it's slack side taught or the belt rides up on the teeth and dies, so it is a bit trickier to overload without exceeding a sane static tension. Tension is usually the design limit for belts, they don't have the reserves that chains do. Sprung idlers on both sides to cope with deceleration is how I'd do it.
Big yup. Me too.
 

FarmBoy

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Joined
Mar 14, 2012
Messages
129
Location
Gainesville, VA
I discovered that 25 years ago when I was tasked with selectinging an upgraded chain for a 240hp drag bike. Chains are generally sized for wear, and road bikes use their max torque capacity for very little time. max chain load is full throttle in 1st gear, even small bikes don't spend long doing that... A belt needs to keep it's slack side taught or the belt rides up on the teeth and dies, so it is a bit trickier to overload without exceeding a sane static tension. Tension is usually the design limit for belts, they don't have the reserves that chains do. Sprung idlers on both sides to cope with deceleration is how I'd do it.
Big yup. Me too.
Yeah, it could use 5 or 10 more pounds in the rear - that’d be less than a 1% increase in the FWB anyway ;)
 
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