Your welcome. Some need to pass on knowledge to the next gen. I need to make a few more in depth videos on some light porting and blueprinting. Maybe the quickest way for tear down too. I have that electric and gas race but need a lot of editing and life has been busy
If you want to go fast use a flat top HUSQVARNA 50 piston on the two piece barrel ......do a squish test and machine the top of barrel to get .6 mm with head installed, machine the head to aim for about 50% area squish band, widen the exhaust port to 70% of the piston diameter and raise the port to about 180 degrees exhaust duration, I think that was about 18mm from TDC you will need to put a degree wheel on and check, use a cheap Chinese 21mm carb and remove the air bleed jet. 145 jet , 4th clip,use those Stainless steel Chinese exhausts and add 5mm to the header pipe.......I raced this combo for years.......5.69hp @10200
Youll notice on the cylinder with fingers the base is significantly wider than on the full port on my setup a full 4mm. The separation is for less friction on the rings and higher velocity up the transfers that and it will also guide the charge , im very hesitant to cut the fingers on my cylinder i need more convincing
Yeah I have tried both (with and w/o fingers), but I port both to the same width and haven't noticed much of a difference. Yes the fingers can help the rings. I personally like the 40mm heads better, they run cooler and can my modified to run with a 44mm. The 40mm also will have higher RPM and run more top speed. But the 44mm will have more takeoff power.
Hey dude, hopefully you're still on here, I need help with gasket on the 3 piece head , The head cap part that splits apart - does it need a copper ring gasket in between the two parts there , or does it need it on the crown of the head, or both? Only one ring gasket supplied in the kit. Usually on a 2 piece head I would expect an o-ring at least. Thanks
Is a 44mm ported cylinder with boost port and ported windows on piston better or worse then a 44mm ported cylinder without boost ports no windows on piston? cheers
A single boost port at the back of cylinder is the best. Premade are nice but they could be a little wider and deeper. And the boost port should be 1-2mm taller than the transfer ports. Also trim the corners of the skirt down, helps with flow from the case to cylinder.
Also, the premade pistons are usually dual window. With a single boost port you need a single window, a round hole drilled in a stock piston works just fine. Dual window only works well with dual boost ports.
@@bdrgarage7039 so rotating the cylinder 90 degrees so that the windows line up with the transfer ports is a ridiculous idea? lolol Thanks btw was trying to make sense of the duel window piston being inline with the exhaust. what size hole?
@@dallas749 the piston windows are at the back of the cylinder opposite the exhaust port. However wide your boost port is, make the circle that diameter. Maybe 1-2mm bigger. Then file the edges smooth. I am gonna do a short video soon, I chopped a 40mm head. Unfinished but will be a lead in. I will show a single window piston at the end. And dont turn the cylinder 90deg. I have seen a few engines with the cylinders turned 180 deg on bicycle projects but never saw them finished.
A piston port head. They also have had some great heads. I unfortunately only have a couple. Most are great, with only a few bad castings. Less than these reed heads. Anything in particular you are looking for? They can be modded well for performance.
I asked a few of older pocket modders. They don't remember any bad castings for the piston port and most work well. Just widen the side ports especially at the base.
Some have tried, for install on a bmx style bicycle. And the projects never finish. If you install upside down the piston also needs to be flipped. However if the exhaust gasses don't escape properly, and unburned fuel, it can sit in the cylinder. Most likely flooded it. I personally haven't even tried.
@@jonbobskunkworks I honestly have not checked, however, it will be buy and test, I really should do that. Once half of my fleet is gone I will. I have been so busy with life and quick flips, I haven't done any videos
Some believe the transfer port fingers are important but they take up space that could be more air and fuel. The older better cylinders did not have fingers (dividers). My opinion is they were put there for emissions. If you leave them and do some porting you will still gain power. Remember these engines are power tool engines, not performance engines like say a honda dirtbike where they are built almost to the max. These were built for longevity. With all the right work, these can be built with triple the power.
@@bdrgarage7039 which one would you prefer, with divider or without??? Am i gonna trim my divider or not? What is the difference? Which one is better??
@@nicky2238 I do use both, only because the nondividers are very hard to find. I have thinned them out and also cut half out. I would stay away from the Hei Ma cylinders (the worst) and the MSD cylinders. Reason, the exhaust port is too low and at BDC the piston is still heavily in the window, which you don't want.
www.amazon.com/XLJOY-44mm-Cylinder-Piston-Pocket/dp/B01N9BSB9M/ref=mp_s_a_1_11?crid=DR2UPLJHF2D6&keywords=47cc+cylinder&qid=1704688403&sprefix=%2Caps%2C165&sr=8-11 Here is that TM head but it has the dividers. Widen the exhaust port by 1mm each side (at the inside), and arch the top, don't touch the lower inside, but the lower outside can be widened.
Funny you asked that. I do have one planned. I personally haven't done one yet. We shall learn together. The head I have is a nice used head but the spark plug hole blew out the threads.
@@bdrgarage7039 oh yeah. I think you've done it before. At first I wanted to imitate the experience you've made on that machine. Sorry if my words are not good I'm a beginner creator from Indonesia 🙏
Thanks for the knowledge man I'm getting an obsession with pocket bikes recently these vids are useful
Your welcome. Some need to pass on knowledge to the next gen. I need to make a few more in depth videos on some light porting and blueprinting. Maybe the quickest way for tear down too. I have that electric and gas race but need a lot of editing and life has been busy
If you want to go fast use a flat top HUSQVARNA 50 piston on the two piece barrel ......do a squish test and machine the top of barrel to get .6 mm with head installed,
machine the head to aim for about 50% area squish band,
widen the exhaust port to 70% of the piston diameter and raise the port to about 180 degrees exhaust duration, I think that was about 18mm from TDC you will
need to put a degree wheel on and check, use a cheap Chinese 21mm carb and remove the air bleed jet. 145 jet , 4th clip,use those Stainless steel Chinese exhausts and add 5mm
to the header pipe.......I raced this combo for years.......5.69hp @10200
Youll notice on the cylinder with fingers the base is significantly wider than on the full port on my setup a full 4mm.
The separation is for less friction on the rings and higher velocity up the transfers that and it will also guide the charge , im very hesitant to cut the fingers on my cylinder i need more convincing
Yeah I have tried both (with and w/o fingers), but I port both to the same width and haven't noticed much of a difference. Yes the fingers can help the rings. I personally like the 40mm heads better, they run cooler and can my modified to run with a 44mm. The 40mm also will have higher RPM and run more top speed. But the 44mm will have more takeoff power.
Thats just because the crank case is complete junk though , cant handle the extra head volume
the 44-6 enbose in the cylinder head a good 49cc engine 2 stroke , Im planning to buy this head.
Just be careful, not all are created equal. Especially the exhaust port, half the time are too low at BDC.
Hey dude, hopefully you're still on here,
I need help with gasket on the 3 piece head ,
The head cap part that splits apart - does it need a copper ring gasket in between the two parts there , or does it need it on the crown of the head, or both? Only one ring gasket supplied in the kit.
Usually on a 2 piece head I would expect an o-ring at least.
Thanks
Is a 44mm ported cylinder with boost port and ported windows on piston better or worse then a 44mm ported cylinder without boost ports no windows on piston? cheers
A single boost port at the back of cylinder is the best. Premade are nice but they could be a little wider and deeper. And the boost port should be 1-2mm taller than the transfer ports. Also trim the corners of the skirt down, helps with flow from the case to cylinder.
Also, the premade pistons are usually dual window. With a single boost port you need a single window, a round hole drilled in a stock piston works just fine. Dual window only works well with dual boost ports.
@@bdrgarage7039 so rotating the cylinder 90 degrees so that the windows line up with the transfer ports is a ridiculous idea? lolol Thanks btw was trying to make sense of the duel window piston being inline with the exhaust. what size hole?
@@dallas749 the piston windows are at the back of the cylinder opposite the exhaust port. However wide your boost port is, make the circle that diameter. Maybe 1-2mm bigger. Then file the edges smooth. I am gonna do a short video soon, I chopped a 40mm head. Unfinished but will be a lead in. I will show a single window piston at the end.
And dont turn the cylinder 90deg. I have seen a few engines with the cylinders turned 180 deg on bicycle projects but never saw them finished.
How do those boost ports work?
Got any information on the cylinder with the intake and exhaust on the sane head
A piston port head. They also have had some great heads. I unfortunately only have a couple. Most are great, with only a few bad castings. Less than these reed heads. Anything in particular you are looking for? They can be modded well for performance.
I asked a few of older pocket modders. They don't remember any bad castings for the piston port and most work well. Just widen the side ports especially at the base.
Normally they come with the exhaust port facing down, can it be installed with the exhaust port facing up and the spark plug down?
Some have tried, for install on a bmx style bicycle. And the projects never finish. If you install upside down the piston also needs to be flipped. However if the exhaust gasses don't escape properly, and unburned fuel, it can sit in the cylinder. Most likely flooded it. I personally haven't even tried.
How big of a cylinder can you get for these? Is 44mm the biggest?
Yes 44mm is the biggest, technically its 47cc. There might be some chainsaw cylinders you could try, I have not
What kind chainsaw cylinders do you recommend? I have a ton of chainsaw stuff!
@@jonbobskunkworks I honestly have not checked, however, it will be buy and test, I really should do that. Once half of my fleet is gone I will. I have been so busy with life and quick flips, I haven't done any videos
I’m digging into it. Thank you for the heads up
Sir, the divider isnt important or not ???
Some believe the transfer port fingers are important but they take up space that could be more air and fuel. The older better cylinders did not have fingers (dividers). My opinion is they were put there for emissions. If you leave them and do some porting you will still gain power. Remember these engines are power tool engines, not performance engines like say a honda dirtbike where they are built almost to the max. These were built for longevity. With all the right work, these can be built with triple the power.
@@bdrgarage7039 which one would you prefer, with divider or without??? Am i gonna trim my divider or not? What is the difference? Which one is better??
@@nicky2238 I do use both, only because the nondividers are very hard to find. I have thinned them out and also cut half out. I would stay away from the Hei Ma cylinders (the worst) and the MSD cylinders. Reason, the exhaust port is too low and at BDC the piston is still heavily in the window, which you don't want.
www.amazon.com/XLJOY-44mm-Cylinder-Piston-Pocket/dp/B01N9BSB9M/ref=mp_s_a_1_11?crid=DR2UPLJHF2D6&keywords=47cc+cylinder&qid=1704688403&sprefix=%2Caps%2C165&sr=8-11
Here is that TM head but it has the dividers. Widen the exhaust port by 1mm each side (at the inside), and arch the top, don't touch the lower inside, but the lower outside can be widened.
@@bdrgarage7039 thankyou sooooooo sooo muchhhh.... 🙏
Nice, how to cut a head cylinder 🙏
Funny you asked that. I do have one planned. I personally haven't done one yet. We shall learn together. The head I have is a nice used head but the spark plug hole blew out the threads.
@@bdrgarage7039 oh yeah. I think you've done it before. At first I wanted to imitate the experience you've made on that machine. Sorry if my words are not good I'm a beginner creator from Indonesia 🙏
I’m tryna build a Superman motor can someone guide me the right way ?
What kind of an engine do you have?