Author Topic: Japauto 1000 VX  (Read 15855 times)

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Offline Tintop

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Re: Japauto 1000 VX
« Reply #50 on: July 08, 2020, 08:20:17 PM »
I know I am bias but the cylinder fin spacing doesn't look good on those cylinders. We had one when my partner and I designed my cylinder.

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Offline MRieck

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Re: Japauto 1000 VX
« Reply #51 on: July 09, 2020, 05:16:42 PM »
 I do have to admit the cooling ability appeared to be much better than the RC block. ;D
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Offline johno

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Re: Japauto 1000 VX
« Reply #52 on: July 09, 2020, 07:18:28 PM »
Its all about surface area baby !
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Offline 754

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Re: Japauto 1000 VX
« Reply #53 on: July 10, 2020, 10:47:41 AM »
Post #45 , rearshock, is that Fournales ?
  The RC block was designed for drag racing, cooling is not the major concern..
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Offline johno

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Re: Japauto 1000 VX
« Reply #54 on: July 11, 2020, 04:03:27 AM »
Frank the Japauto cylinders with less fins than Mikes were used in endurance racing where cooling was VERY important,    You can always warm up a bike more but its difficult to make them run cooler, on air cooled engines surface area is what its all about baby.  ;). The amateur manufacturers use less fins because its cheaper to produce Im sure, they didn't have computers or cnc machines in RC's days Frank, I bet if they did have them we would have seen a better product from ol Russ.  ;D
GRASSHOPPER SOHC HONDAS ARE THE MEANING OF LIFE.

Offline MRieck

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Re: Japauto 1000 VX
« Reply #55 on: July 11, 2020, 10:23:17 AM »
Frank the Japauto cylinders with less fins than Mikes were used in endurance racing where cooling was VERY important,    You can always warm up a bike more but its difficult to make them run cooler, on air cooled engines surface area is what its all about baby.  ;). The amateur manufacturers use less fins because its cheaper to produce Im sure, they didn't have computers or cnc machines in RC's days Frank, I bet if they did have them we would have seen a better product from ol Russ.  ;D
After measuring the RC blocks it was evident the machining was "just good enough". Keith Byers also found the bores weren't evenly spaced and were actually forward from where they were supposed to be. I can only imagine how hot those RC blocks would get in street riding.....a big heat sink. Like Frank said....for dragracing not a problem. Any other application...forget about it.
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Offline PeWe

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Re: Japauto 1000 VX
« Reply #56 on: July 11, 2020, 11:22:49 AM »
Mikes block work fine for 200-300km trips on nice country roads. Some up to +100-120mph throttling feeling the torque.

I have done 6000 km of that this year, mostly  end of March to mid June. Rear tire worn out after 5000km. It was new in January.

No problem to cruise all day long on highways, stop for refueling.
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Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
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Offline valt

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Re: Japauto 1000 VX
« Reply #57 on: July 12, 2020, 04:57:22 PM »
Frank the Japauto cylinders with less fins than Mikes were used in endurance racing where cooling was VERY important,    You can always warm up a bike more but its difficult to make them run cooler, on air cooled engines surface area is what its all about baby.  ;). The amateur manufacturers use less fins because its cheaper to produce Im sure, they didn't have computers or cnc machines in RC's days Frank, I bet if they did have them we would have seen a better product from ol Russ.  ;D
After measuring the RC blocks it was evident the machining was "just good enough". Keith Byers also found the bores weren't evenly spaced and were actually forward from where they were supposed to be. I can only imagine how hot those RC blocks would get in street riding.....a big heat sink. Like Frank said....for dragracing not a problem. Any other application...forget about it.

It was always my understanding that the RC jugs were really just for drag racing. Is that wrong? I can't imagine it would be very happy cruising around in traffic.