14cc head help

#21
I'm starting to think that a 14cc milled .65 was a bad choice
Its a bad choice when things break on you.
This is simply a learning curve your on right now.
And you seem to be picking up some pointers as you go.

Generaly I sugest street engines not exceed 11:1 and stock cams are best for less than that to prevent detonation.

You could use a thicker head gasket, but that may not be enough to prevent trouble.
Is there E 85 in your area?
You may have choice of fuel thats not going to cost you much.
 
#26
But what if someone WANTED to rub the miked 14 cc head abs flat top piston and didn't really know enough to know what they were wanting to run. I.e. fuel, compression ratio. They simply want to go fast and are learning.

So what would be needed to run said setup
 
#27
I don't think anyone is not saying it won't run, its just how long will it run.:wink:
If I remember correctly this motor does not have a (billet rod) yet
( billet flywheel)
(stainless valves)
Right length (push rods)
Fuel probably (alcohol)
Block side cover (studs)
Head (studs)
Head gasket ( ?? )
 
#28
Get the fattest head gasket you can find or by a new head. I think I paid $40. from ARC for my 14cc
i got mine on ebay shipped to my door for $30. It came with valves, keepers, rockers, etc. I did have to buy a new valve cover because I had the 5 bolt version and went to the 4 bolt version. They're fairly cheap. However, your head will probably still work just fine. Get a thick gasket and figure out how long you need your pushrods to be.
 
#29
But what if someone WANTED to rub the miked 14 cc head abs flat top piston and didn't really know enough to know what they were wanting to run. I.e. fuel, compression ratio. They simply want to go fast and are learning.

So what would be needed to run said setup
It's safe to say that almost everything that moves should be replaced when you're dealing with monster compression and high rpms. I kept the crank, but a new cam will be needed. The stock cams tend to be made of lower quality metals and won't last with anything over 18 lb. springs. The pushrods may bend with anything over 18 lb. springs. The valves will break where the valve keeper is if the springs are over 18 lb. springs. Why run anything over 18 lb springs? Because the really aggressive cams need the stiffer springs. I would definitely recommend the billet rod and flywheel. If you're gonna put this much money into a build, you're surely gonna run a good carb. If you're gonna get the motor to breathe, you gotta get the exhaust to breath better, so you'll need a decent header. Some will even suggest swapping out the studs that hold the motor together. I'd say that is debatable, but the studs holding the head will certainly need some attention. I don't know about the studs holding the side cover on. That is the cheapest swap of all of the mods listed. I'm sure there is something that I'm missing, but I know there are a ka-jillion threads on this site giving advice on what to do to build a ridiculous motor. The truth is, you don't need to put that much money into a build to get it to go fast. If you're young, you're gonna want that money back in a few years to put into a nice car (to turn heads and pick up girls). If you're old...well...we do dumb things all of the time. And we're obviously not interested in impressing girls, or we wouldn't be spending so much time and money playing with mini bikes.
 
#31
A few years back if you just bolted on a 14cc head to a bone stock clone with a dish piston you got into the 9.5 10:1 compression range.

This was a good modification because it burned pump gas and with a little effort the short comings in flow between the 22 and 14 could be worked out so you did not loose much of anything anywhere.
And you GAINED improved torque everywhere, bottom end and midrange.

A stock clone could handle the extra compression if you had some clearence on the rod and everything was tight ( a low level blue print job ).

If you added some billet parts and removed the governor the 14cc was still a good choice.
Yes the top end would start to fall off early but there were cheap entry level cams that worked with the 18 pound G200 springs to help compenesate.

These engines were hard on the clone valve train and could not turn high rpm for very long.
But they made great sprint engines and you could keep one running a long time if you were careful.

But that was then.
Clones got bigger ( 212 cc )
Clone parts got cheaper.
CLone aftermarket race stuff got better and still remained fairly cheap.

This is where we are today and where folks get into trouble.
You can make some devilshly high compression engines and get all kids of cams and race parts these days without advice for the sellers or discussion about what good and bad combinations.....

SO when more experience builders try and explain things about why this is good and that is bad you do now see the whole picture.
Yes compression is good!
But realisticly you don't gain much after 11:1 on a street gas motor for the increase in cost and complexity.
ANd you need the right cams too.
High ( I mean in excess of 11:1 ) compression engines need the correct cams to ensure the cylinder is flow the correct amount of air/fuel mix at the rpm range the static compression will work best.
In other words if you are trying to get your cylinder presure high at the range whereyou can set the engine to make the max power.
If it starts to spike cylinder presure at too low a range you get into early fuel ignition rpoblems and power loss ( potential engine damage too ).
You can work around this with timing and jetting, but you loose power in the range where you stood to make the most gain for your expensiive parts and time.

The real trick of building a tuning an engine like this is to select the right cam, the right static compression, the right flowing head and parts and of course the right amount of static timing.
Get all these things right and you make good power at the range you built for and still have a reasonable amount of broad flat torque at other RPM and good throttle response at others.

Get it wrong and you have a dog that runs weak and slow off the line and is nothing more than peaky where it does work good.
At worst you can get a little guy with a much simpler engine make you look a fool because his bike runs so much better than yours he runs circles around you.

SO for most people I say run something under 11:1 or lower range.
Stick with proven cams that make more power in this range and do not have excessiive lift or durration.
The Momba for example is ground for kind of engine ( and Tim can sell you a tweaked version for more low end or more top end, but you can have both ).

Use the strong parts where the engine is weakest.
The clone valve train is bad.
The clone ignition is no hell.
The rod and flywheel are absolute safety requirements.

Now if you ask the right questions and buy the right parts its not that hard to double the power output of a clone and still have something that runs good ( and is super reliable ).
You can triple the power of a clone too!
But now you have something that is not so easy build, morew expensive and ill tempered.

SO as I have said before often you shoudl shoot for an engine that makes less than 15 hp.
The rest of the performace package after that becomes better braking, better cutches and better driving.

A fast bike is all about a package ( not just the engine, the whole bike ).
You can beat a very expensive engine by just having a well set up bike with less power.
 
#33
A few years back if you just bolted on a 14cc head to a bone stock clone with a dish piston you got into the 9.5 10:1 compression range.

This was a good modification because it burned pump gas and with a little effort the short comings in flow between the 22 and 14 could be worked out so you did not loose much of anything anywhere.
And you GAINED improved torque everywhere, bottom end and midrange.

A stock clone could handle the extra compression if you had some clearence on the rod and everything was tight ( a low level blue print job ).

If you added some billet parts and removed the governor the 14cc was still a good choice.
Yes the top end would start to fall off early but there were cheap entry level cams that worked with the 18 pound G200 springs to help compenesate.

These engines were hard on the clone valve train and could not turn high rpm for very long.
But they made great sprint engines and you could keep one running a long time if you were careful.

But that was then.
Clones got bigger ( 212 cc )
Clone parts got cheaper.
CLone aftermarket race stuff got better and still remained fairly cheap.

This is where we are today and where folks get into trouble.
You can make some devilshly high compression engines and get all kids of cams and race parts these days without advice for the sellers or discussion about what good and bad combinations.....

SO when more experience builders try and explain things about why this is good and that is bad you do now see the whole picture.
Yes compression is good!
But realisticly you don't gain much after 11:1 on a street gas motor for the increase in cost and complexity.
ANd you need the right cams too.
High ( I mean in excess of 11:1 ) compression engines need the correct cams to ensure the cylinder is flow the correct amount of air/fuel mix at the rpm range the static compression will work best.
In other words if you are trying to get your cylinder presure high at the range whereyou can set the engine to make the max power.
If it starts to spike cylinder presure at too low a range you get into early fuel ignition rpoblems and power loss ( potential engine damage too ).
You can work around this with timing and jetting, but you loose power in the range where you stood to make the most gain for your expensiive parts and time.

The real trick of building a tuning an engine like this is to select the right cam, the right static compression, the right flowing head and parts and of course the right amount of static timing.
Get all these things right and you make good power at the range you built for and still have a reasonable amount of broad flat torque at other RPM and good throttle response at others.

Get it wrong and you have a dog that runs weak and slow off the line and is nothing more than peaky where it does work good.
At worst you can get a little guy with a much simpler engine make you look a fool because his bike runs so much better than yours he runs circles around you.

SO for most people I say run something under 11:1 or lower range.
Stick with proven cams that make more power in this range and do not have excessiive lift or durration.
The Momba for example is ground for kind of engine ( and Tim can sell you a tweaked version for more low end or more top end, but you can have both ).

Use the strong parts where the engine is weakest.
The clone valve train is bad.
The clone ignition is no hell.
The rod and flywheel are absolute safety requirements.

Now if you ask the right questions and buy the right parts its not that hard to double the power output of a clone and still have something that runs good ( and is super reliable ).
You can triple the power of a clone too!
But now you have something that is not so easy build, morew expensive and ill tempered.

SO as I have said before often you shoudl shoot for an engine that makes less than 15 hp.
The rest of the performace package after that becomes better braking, better cutches and better driving.

A fast bike is all about a package ( not just the engine, the whole bike ).
You can beat a very expensive engine by just having a well set up bike with less power.
When NOS speaks, I listen. Good stuff here.
 
#34
Thanks for all your help guys I'm buying a bsp motor and putting my head away on my dresser until I get all the parts in need which are
Black mamba cam
Rod
Flywheel
Ss valves
 
#36
When NOS speaks, I listen. Good stuff here.
I am far from the final word.
Many other people here are worthy of listening too.

Unless you really know me you should always consider other opinions.
This is the internet.
I could be 9 years old the way I spell and type...

I have been thinking a lot about these questions.
I get tired of repeating te advice many people inclusing myself make on this subject.
I think maybe we need a new thread about a street engine.
We should lay down some build specs and make it sticky so beginers have something to read and use as a template.
It won;t solve all the questions but its a good idea I think.

Double triple clone build
This is old but its a great read.
if you were to build a 212 like this with some of the improved parts today you could easily make a little more than double the power for triple the cost.
Project triple double is a test to find a dollar to horsepower ratio of a 200 cc OHV engine, specifically a Chinese made clone
 
#37
I am far from the final word.
Many other people here are worthy of listening too.

Unless you really know me you should always consider other opinions.
This is the internet.
I could be 9 years old the way I spell and type...

I have been thinking a lot about these questions.
I get tired of repeating te advice many people inclusing myself make on this subject.
I think maybe we need a new thread about a street engine.
We should lay down some build specs and make it sticky so beginers have something to read and use as a template.
It won;t solve all the questions but its a good idea I think.

Double triple clone build
This is old but its a great read.
if you were to build a 212 like this with some of the improved parts today you could easily make a little more than double the power for triple the cost.
Project triple double is a test to find a dollar to horsepower ratio of a 200 cc OHV engine, specifically a Chinese made clone
Don't worry, NOS. I have a handful of guys on here that I admire and trust. I don't know any of you, but your advice seems to be spot on and genuine most of the time. There are others on here that I avoid like the plague. I think a sticky is a great idea, but a lot of folks are pretty impatient, and they may pass it up. Still worth it in my opinion.
 
#40
I am far from the final word.
Many other people here are worthy of listening too.

Unless you really know me you should always consider other opinions.
This is the internet.
I could be 9 years old the way I spell and type...

I have been thinking a lot about these questions.
I get tired of repeating te advice many people inclusing myself make on this subject.
I think maybe we need a new thread about a street engine.
We should lay down some build specs and make it sticky so beginers have something to read and use as a template.
It won;t solve all the questions but its a good idea I think.

Double triple clone build
This is old but its a great read.
if you were to build a 212 like this with some of the improved parts today you could easily make a little more than double the power for triple the cost.
Project triple double is a test to find a dollar to horsepower ratio of a 200 cc OHV engine, specifically a Chinese made clone
I'm sorry nos but I don't get what you mean by "if you were to build a 212 like this with some of the improved parts today you could easily make a little more than double the power for triple the cost" so to get double the power if have to put 1500$ into it triple the price
 
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