TRX250R.ORG
Workshop => Engine and Bottom End => Topic started by: swanitalia on December 28, 2015, 04:42:21 PM
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Does anyone know which CR250 head fits on the TRX250r cylinder? I'm not talking about the gasket, i'm talking the actual head.
I know I need the head with the single coolant outlet so it cannot be the early year heads up till 92. 92+ heads have the single outlet but I do not know which head can fit.
Any help would be appreciated.
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Can I ask why you want to do this?
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I would think compression Jared. I thought the ATC heads more compression than trx heads
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The CR250 head has a thicker cast then the TRX/ATC heads. It can be cut a little bit more and it holds more coolant, it's basically a cheap coolhead for a fraction of the price.
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I know the '87 head gasket interchanges.
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I know the '87 head gasket interchanges.
I know the 86-89 head gaskets have the correct flow patterns, but the head has dual coolant outlets. Thanks for the input
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The 2 outlet style works when using the factory cr Y fitting. I have used it...
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the engine with the best cooling ive seen with my own eyes is newer ktm. the head isnt a big pompous looking thing with gallons of water but rather its fairly small with passages that mimic the combustion chamber top side. alot can be learned from the oem manufacturers and their latest and greatest designs. why aftermarket companies continue to make these big heads with rediculous amounts of water capacity is a mystery. its likely their heads have little to no testing
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The 2 outlet style works when using the factory cr Y fitting. I have used it...
Do you know what CR Y fitting I would need?
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Do you know what CR Y fitting I would need?
Here is the Y fitting:
http://www.partzilla.com/parts/detail/honda/HP-19069-KA4-730.html
(http://sharkshifter.com/zc/images/medium/crhose-007.jpg)
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Like that swan. Genuine honda cr part. I ran the other way vs that photo of course and the y provided plug change room. That was years ago......
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the engine with the best cooling ive seen with my own eyes is newer ktm. the head isnt a big pompous looking thing with gallons of water but rather its fairly small with passages that mimic the combustion chamber top side. alot can be learned from the oem manufacturers and their latest and greatest designs. why aftermarket companies continue to make these big heads with rediculous amounts of water capacity is a mystery. its likely their heads have little to no testing
I agree.
Making a head or cylinder hold more coolant in the water jacket does not improve the heat transfer from the head and or cylinder to the coolant flowing through them. Adding volume to the coolant system does allow one to run at lower speeds for a longer period of time before the coolant will reach the a critical temperature for a given engine.
The difference in coolant volume from an OEM head to one of the aftermarket heads that boast their head design holds more coolant is insignificant in regards to the amount of time it would buy you before the coolant reaches a critical temperature.
If all we were concerned about was coolant temperature, we could remove the radiator and add a 5 gallon coolant reservoir and let the engine just circulate the coolant through the engine and coolant reservoir. On a 50 hp engine running wide open we could run it for about 15 minutes before it would boil the coolant without a radiator cap. Install the radiator cap and it would now take about 20 minutes to boil the coolant.
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i guess the coc went on a ramble about coolheads being so strong and some thermal mumbo jumbo nonsense. only heads i ever seen break was coolhead domes because theyre crap. he wouldnt know what a good head design looked like if it kicked him in the balls