Noss head

[2003LimitedBanshee]

The person that wrote this I believe lightened your flywheel 2003 limited banshee.plus bumping up the comp. adds heat,which would offset the 5%heat reduction.

 

Nope, it looks like Blue Duece (who's, not to start a flame war as he put it 3 years ago, posts I haven't been impressed with) posted that, not to be confused with boonman. Now, take note I never said it would cool by X% better, but I can tell you that I used to be able to run the crap out of my bike at the dunes and get it to spit coolant after long climbs, now it never spits a drop. And for a further less scientific yet explanation see how long you can hold you hand on a stock head that has been running hard compared to a coolhead. Neither one is very long, but I can definitely stand it longer with my NOSS head. Additionally, if you look at a NOSS or other coolhead when it is in pieces you will see that a good deal of surface area around the combustion chamber has better contact with the coolant. So, I will stick to my guns that the coolheads are more efficient at transfering heat away from the cylinders. So even with the added compression, which you are correct would lead to higher combustion temps, if you're head is more efficient at transfering that heat away, you still have a net decrease in the residual cylinder temp.

[06BaNsHeE]

Just Have Your stock head milled and tell the person whos doing it what type of gas you want to run.And use that money for some other mods like maybe tires or w/e

[FireHead]

Nope, it looks like Blue Duece (who's, not to start a flame war as he put it 3 years ago, posts I haven't been impressed with) posted that, not to be confused with boonman. Now, take note I never said it would cool by X% better, but I can tell you that I used to be able to run the crap out of my bike at the dunes and get it to spit coolant after long climbs, now it never spits a drop. And for a further less scientific yet explanation see how long you can hold you hand on a stock head that has been running hard compared to a coolhead. Neither one is very long, but I can definitely stand it longer with my NOSS head. Additionally, if you look at a NOSS or other coolhead when it is in pieces you will see that a good deal of surface area around the combustion chamber has better contact with the coolant. So, I will stick to my guns that the coolheads are more efficient at transfering heat away from the cylinders. So even with the added compression, which you are correct would lead to higher combustion temps, if you're head is more efficient at transfering that heat away, you still have a net decrease in the residual cylinder temp.

 

I believe that there are to different two different subjects to be discussed when comparing an OEM head to a Brand X cool head. First, is obviously how efficiently heat is removed from the engine, which is a very complex subject. Second, is the uniformity of heat transfer through the system. :geek:

[brugal]

Nope, it looks like Blue Duece (who's, not to start a flame war as he put it 3 years ago, posts I haven't been impressed with) posted that, not to be confused with boonman. Now, take note I never said it would cool by X% better, but I can tell you that I used to be able to run the crap out of my bike at the dunes and get it to spit coolant after long climbs, now it never spits a drop. And for a further less scientific yet explanation see how long you can hold you hand on a stock head that has been running hard compared to a coolhead. Neither one is very long, but I can definitely stand it longer with my NOSS head. Additionally, if you look at a NOSS or other coolhead when it is in pieces you will see that a good deal of surface area around the combustion chamber has better contact with the coolant. So, I will stick to my guns that the coolheads are more efficient at transfering heat away from the cylinders. So even with the added compression, which you are correct would lead to higher combustion temps, if you're head is more efficient at transfering that heat away, you still have a net decrease in the residual cylinder temp.

BOONMAN wrote that .If you read the whole thing you would see that, at the bottom of the quote Duece agrees with boon.The reason I quoted Blue Duece's answer to boonman is because he agreed with boon and those two men know a thing or two about banshees.If you like Ill go back and get boon's original quote?

[FireHead]

If this turns into a pissing match...............somebody can send me an OEM head and gasket and I will run it back to back with a cool head on an engine dyno. Y'all can figure what you want to be monitored. The instrumentation package I put together could be viewed as being subjective, so you can sort that out. :geek:

[brugal]

If this turns into a pissing match...............somebody can send me an OEM head and gasket and I will run it back to back with a cool head on an engine dyno. Y'all can figure what you want to be monitored. The instrumentation package I put together could be viewed as being subjective, so you can sort that out. :geek:

No, hes was wright it looks like the quote was from Duece, so I just wanted to explain why it looked that way.I qouted boonman because I remember the topic from acouple of years back and its a great breakdown on the topic.No pissing match.

[Banshee Eh?]

Thanks for the replys guys. I think i will go with the noss head cause of the fact that i am at such a high elevation and it would be good for me to be able to change the domes say if i ever decided to go riding down in the sand dunes or at sea level.

 

Also i am getting about 90 PSI compression in the cylynders when i do a compression test, does that sound about right for a motor with only pipes and reeds and no other mods at a elevation of about 3100 ft? It is a fairly new banshee maybe 20 hours on the motor.

 

Thanks

Kevin

[FireHead]

Thanks for the replys guys. I think i will go with the noss head cause of the fact that i am at such a high elevation and it would be good for me to be able to change the domes say if i ever decided to go riding down in the sand dunes or at sea level.

 

Also i am getting about 90 PSI compression in the cylynders when i do a compression test, does that sound about right for a motor with only pipes and reeds and no other mods at a elevation of about 3100 ft? It is a fairly new banshee maybe 20 hours on the motor.

 

Thanks

Kevin

 

That compression is quite low. I would be thinking that 110-115 psi would be the lowest you would be at with a stock head and porting. Are you sure the engine only has 20 hours on it?

[dajogejr]

Thanks for the replys guys. I think i will go with the noss head cause of the fact that i am at such a high elevation and it would be good for me to be able to change the domes say if i ever decided to go riding down in the sand dunes or at sea level.

 

Also i am getting about 90 PSI compression in the cylynders when i do a compression test, does that sound about right for a motor with only pipes and reeds and no other mods at a elevation of about 3100 ft? It is a fairly new banshee maybe 20 hours on the motor.

 

Thanks

Kevin

 

Sounds a little low, even at that elevation.

 

I know this sounds stupid, but I have to ask.

a. what kind of compression tester is it? If it's a 10 dollar auto store bargain bin special, throw it out and get a good one.

b. Are you checking it warm or cold? Are you holding the throttle wide open and kicking it until it doesn't climb anymore? It often can take 15 to 20 kicks to get the last few PSI out of it.

 

As said, on a stock head at your elevation I would at least expect to see over 100PSI on a slightly worn motor....if 90PSI is correct, I'd be putting a fresh top end on at the same time as the head...no reason to crank up the compression on a worn motor...

[bansheeseat$$]

Thanks for the replys guys. I think i will go with the noss head cause of the fact that i am at such a high elevation and it would be good for me to be able to change the domes say if i ever decided to go riding down in the sand dunes or at sea level.

 

Also i am getting about 90 PSI compression in the cylynders when i do a compression test, does that sound about right for a motor with only pipes and reeds and no other mods at a elevation of about 3100 ft? It is a fairly new banshee maybe 20 hours on the motor.

 

Thanks

Kevin

 

Kevin that compression is very low.I get 120 psi out of stock engines at 4500 feet.I would look into a top end while your installing a head.My .02 cents.

[Banshee Eh?]

Sounds a little low, even at that elevation.

 

I know this sounds stupid, but I have to ask.

a. what kind of compression tester is it? If it's a 10 dollar auto store bargain bin special, throw it out and get a good one.

b. Are you checking it warm or cold? Are you holding the throttle wide open and kicking it until it doesn't climb anymore? It often can take 15 to 20 kicks to get the last few PSI out of it.

 

As said, on a stock head at your elevation I would at least expect to see over 100PSI on a slightly worn motor....if 90PSI is correct, I'd be putting a fresh top end on at the same time as the head...no reason to crank up the compression on a worn motor...

 

 

LOL yeah it is a cheaper one, not a really cheap one I will try to get another one and test it with that as well.

 

I will warm it up and try it again, I never thought of holding the throttle wide open. I will do that! I was also reading in the manual to soak the air filter with 10W 30 oil and before it was done with the yamaha air filter oil which was fairly thick like gear oil.

 

I will start with that and go from there!

 

Thanks

Kevin

[FireHead]

LOL yeah it is a cheaper one, not a really cheap one I will try to get another one and test it with that as well.

Thanks

Kevin

 

From my experience there can be a bit of variation across all compression testors no matter who made them. A more expensive is a great tool to have and you certainly gain repeatebility and ease of use by spending more money on a tester.

 

It always makes me giggle to read about people and their compression testers. Most people are not dumb and are using their testers properly most of the time, but it amazes me how many people have malfunctioning compression testers. :biggrin:

[Banshee Eh?]

From my experience there can be a bit of variation across all compression testors no matter who made them. A more expensive is a great tool to have and you certainly gain repeatebility and ease of use by spending more money on a tester.

 

It always makes me giggle to read about people and their compression testers. Most people are not dumb and are using their testers properly most of the time, but it amazes me how many people have malfunctioning compression testers. :biggrin:

 

Hehe I am kinda a noob at this stuff so i am still kinda learning the ropes. But i am sure in this case it was the cheap tester i bought If it was a snap on i woulda got a better reading

 

LOL it kinda sucks livin here in the boonies everything costs a fortune and there is no selection of tools so i have to drive 2 hours just to get to a small city and have a decent selection. maybe i will have to invest in some micrometers and telescopic guages so i can measure the cylynders up.

 

My machine i have at 105 PSI so i assume that is a bit better. Hehe i am not too sure what i wanna do now. If i do decide to tear it appart and take a look inside i am thinkin i might send it away for a port job on it. Anyone tell me what i could expect from a port with a stock stroke and bore? Is there much in the way of overheating or reliability issues or faster wear when you get one done. I been kinda reading the archives and not too many people have a ported machine with stock stroke etc...

 

 

 

Thanks

Kevin

[blowit]

I have proof that a Pro Design (I think Noss heads are a bit different with respect to coolant passages) cool head has less of a coolant pressure delta than a stock head. That's about it. Otherwise, my statement is based off of my shitty memory of what I have seen with thermocouples on the dyno. :geek:

 

 

We have not actually run testing just on cooling with an aftermarket billet head but we run most of our guys with digital temp gauges and I will say minimal temp drop. Also, where are you taking a temp reading from? Yep, the head may be able to drop "head" temps a little through better flow and volume of fluid BUT, putting the DA thermodynamics to it, basically, it would take longer for the bike to get hot but still would if there is a real dissipation issue. And there is on the banshee. More air flow, better radiator, better coolant flow pattern. You have to think that as you raise the HP in an engine, you have more HP in heat to dissipate.

 

Also, do you want an ice cold head? I will let flame head take that one out in depth but cool cylinders and warmer head are much better for efficient burn. We feel the key in the two stroke head is to super atomize the fuel charge just before combustion thus helping everything to lite up upon ignition thus reducing a chance for detonation. We actually run motors over 200psi static with pump fuel in detonation testing. Anyway, coolheads have there place but not in drastically reducing engine temps.

 

 

Brandon

[FireHead]

We have not actually run testing just on cooling with an aftermarket billet head but we run most of our guys with digital temp gauges and I will say minimal temp drop. Also, where are you taking a temp reading from? Yep, the head may be able to drop "head" temps a little through better flow and volume of fluid BUT, putting the DA thermodynamics to it, basically, it would take longer for the bike to get hot but still would if there is a real dissipation issue. And there is on the banshee. More air flow, better radiator, better coolant flow pattern. You have to think that as you raise the HP in an engine, you have more HP in heat to dissipate.

 

Also, do you want an ice cold head? I will let flame head take that one out in depth but cool cylinders and warmer head are much better for efficient burn. We feel the key in the two stroke head is to super atomize the fuel charge just before combustion thus helping everything to lite up upon ignition thus reducing a chance for detonation. We actually run motors over 200psi static with pump fuel in detonation testing. Anyway, coolheads have there place but not in drastically reducing engine temps.

Brandon

 

When I was screwing around monitoring a Banshee ening cooling circuit on a dyno I had thermocouples on the head at the coolant inlet and outlet, one over each cylinder, the water pump, under each cyclinder on the engine case, and at the base of each cooling jacket. Since I was on an engine dyno, I was running the house cooling system and not a Banshee radiator. Even with the house cooling system, engine still ran hot and had a very uneven heat rejection plume across the cylinders (the dyno cells also have heat sensitive IR cameras in them).

 

As eluded to by Blowit, a spark ignited, gasoline fueled, engine performs at it's best on the verge of detonation and thermal run away. In other words, the engine is at it's best right before it blows up.

 

The most intersting thing that I have learned with regard to heat management of two stroke engines is that with in reason it doesn't matter what the cooling system of the engine is doing as long as it keeps the engine from auto igniting, seizing, or similair. What does make a huge difference in power out put is the temperature at which you keep the crank chamber. As a general rule, the cooler the crank chamber is kept with the rest of the engine at normal operating temperature, the more power you will make. :geek: