High compression head............
- Thread starter geebt48cc
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Deleted member 12676
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I think it has a squish band but I have tested both types of heads and it makes no difference. That is because a small bore engine does not have much distance from the spark plug to the outer edge of the cylinder. The flame does not have far to travel and so does not need the help of extra turbulence caused by a squish band.
The only advantage to be had by the optional head (for you) is the extra cooling because of extra surface area.
For more info on the head you could look at this thread: http://www.motoredbikes.com/showthread.php?t=25506
The only advantage to be had by the optional head (for you) is the extra cooling because of extra surface area.
For more info on the head you could look at this thread: http://www.motoredbikes.com/showthread.php?t=25506
I personally have never used a manic mechanic head because much of the reviews I read also said they did not notice any increase in power. However, I have used a puch moped high compression head and I can tell you that it has definetly made a difference in performance. Depending on which engine you have, this is an exact size bolt on. I have two of these heads. First is on an old 66cc grubee starfire motor and the head needed no modifications the fit. Second is on a grubee super rat motor and I had to expand the mounting holes on the head. Nothing a little bit of time and a dremel couldn't handle though. Definite increase in low end torque, however the one downside is it makes the engine much more difficult to start.
Hope this helps
Hope this helps
richirich1113
Member
hi, Geebt48cc , its been awhile since we exchanged posts, since then ive changed motors and did alot of upgrading, on the other site under the "mountain and road bikes" the thread "genisis 29r almost done?" is my bike. i have the MM head. i did notice alot of improvement over the stock angle fire head. there is alot more compression. Now when i start peddling and pop the clutch the back tire actually skids then fires right up on the compression stroke. There is definatly more torque to the motor. it also changed the sound to a more throaty healthy sound. The motor also does run alot cooler ,even after riding it hard it seems like just minutes after shutting it down its back to cool to the touch. If you are thinking about getting one , id say go for it
But alas after all that work, my bike now sits in the garage thanks to a local rookie cop trying to save the world from MBs. WA laws suck!!!!
But alas after all that work, my bike now sits in the garage thanks to a local rookie cop trying to save the world from MBs. WA laws suck!!!!
Hey, Rich, I'm hearing that story more and more about police. I've not had any problems, but I've just been not so much the right place YET? What is going on there in WA?
So, I milled head down flush, and even pulled head gasket off.(only with slant) I've put about total 400 miles on this 66cc and the last 170 have been when milled. Yes, major compression here as well. Bike and I weigh about 340lbs and will run 98% hills here in SW Va at decent pace without the pedal thing.
Rich, do you know if size 700X47C would work on this 2009 Schwinn gateway? I'm really wanting to get the widest tire for pavement that will work? Uno stability is what I'm after, and can still run upper twenties ok.
Glen
So, I milled head down flush, and even pulled head gasket off.(only with slant) I've put about total 400 miles on this 66cc and the last 170 have been when milled. Yes, major compression here as well. Bike and I weigh about 340lbs and will run 98% hills here in SW Va at decent pace without the pedal thing.
Rich, do you know if size 700X47C would work on this 2009 Schwinn gateway? I'm really wanting to get the widest tire for pavement that will work? Uno stability is what I'm after, and can still run upper twenties ok.
Glen
richirich1113
Member
Well the 47c would be like a 1.85 inch tire, on my genisis the tires are 29x 1.65. The 700 is the same as 29" . For me the 1.65 are stable and handle good , but im only weighing 170. I think being a larger diameter tire helps with the stability. So i would think a 700x 47would probably work out ok.
And about the cops , here in Wa the law tecnically make all ICE bicycles illegal no matter what the cc. To be legal it would have to be state patrol inspected and meet all the equipment requirments like a motorcycle and have to be titled and licenced and DL required. Alot of areas people have been getting away with it but really its just a matter of time and a bored cop. The cop was hoping for a dui arrest, before he even ran my name he told me if i have a suspended or dui I was going to jail. since i just dont have one he let me go but made it clear if i was seen again id go to jail and bike impounded. in this small town you would be seen.but he did say if i had an electric bike i wouldnt be hassled.
So you can check out my electric in the electric section under HI-POWER CYCLES 104 Ebike. Its not exactly legal but its electric hehe.
And about the cops , here in Wa the law tecnically make all ICE bicycles illegal no matter what the cc. To be legal it would have to be state patrol inspected and meet all the equipment requirments like a motorcycle and have to be titled and licenced and DL required. Alot of areas people have been getting away with it but really its just a matter of time and a bored cop. The cop was hoping for a dui arrest, before he even ran my name he told me if i have a suspended or dui I was going to jail. since i just dont have one he let me go but made it clear if i was seen again id go to jail and bike impounded. in this small town you would be seen.but he did say if i had an electric bike i wouldnt be hassled.
So you can check out my electric in the electric section under HI-POWER CYCLES 104 Ebike. Its not exactly legal but its electric hehe.
Da"", trying to show you who's wearing the badge huh?! Uno, that's just so uncalled for!! I get the biggest kick out of taking the time for any of the" boys in blue" using it to pull over such a petty offence? That does nothing but make the police department overall look very weak. Just think of all of the stuff that's taking place in comparison!!!!!!!!!!!~
.............SAD, very sad............ PS-Looks like he would of used his stun-gun on you? It really does sound like you were out of control.
.............SAD, very sad............ PS-Looks like he would of used his stun-gun on you? It really does sound like you were out of control.
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richirich1113
Member
yep , just a rookie hoping for a suspended/dui arrest. you know i was not speeding ,i was wearing my helmet. I told him "com on ,there are only two other MBs in the whole town. he tells me " i know ive already stopped them and told them the same thing" what a jerk. And the funny thing is i was contacted by another member that lives in the next town 20mi away and he told me the police srgt. there is allowing them to ride with no problems. Unbelievable.. At least he let me peddle it home , which i just went around the corner fired it and hauled *** home. me peddle- i dont htink so. Well unless the laws change somehow my gas bike is now a dead issue 
lazylightning@mail.r
Active Member
Hi Glen,
Can I ask you why you didnt try the milled down stock head without the head gasket? Why only the slant? I milled my stock head down to the fin level surface and polished the inside of the hemi. With the spark plug in, the end of the spark plug is still down in the threaded hole and nowhere near the level of the hemispherical combustion chamber area. The piston at top dead center is still far from reaching the top of the block, 3 or 4 mm to go. I don't see any chance of the piston even coming close to the head or plug. The bikes got alot more pep since I modified the stock head. I'm using a 35 tooth rear sprocket and my jet is bored out to .8mm and needle is all the way down for more leaness at low speed. I haven't tried it at richer with the higher compression yet.
Paul
gothicguy64
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if i may
my rse 48cc motor has a rse billet head an is far superieror to a stock motor
many a time i have seen another pushie an out dragged it .
mind my motor is ported an has a ceramic topped piston ummm billet head billet inlet ummm billet cover ,billet clutch lever all rse aussie made
bloody pity the donor motor is a import ohhhh well
3500 km later an im yet to get a oil leak or petrol leak ,flat (lol)...i run mr tuffy tyre liners .but i digress
brad
sydney
my rse 48cc motor has a rse billet head an is far superieror to a stock motor
many a time i have seen another pushie an out dragged it .
mind my motor is ported an has a ceramic topped piston ummm billet head billet inlet ummm billet cover ,billet clutch lever all rse aussie made
bloody pity the donor motor is a import ohhhh well
3500 km later an im yet to get a oil leak or petrol leak ,flat (lol)...i run mr tuffy tyre liners .but i digress
brad
sydney
