Dax gp50 9hp wow !!

ah, sounds simple!

i just wonder hows the reliablity however vs a 4 stroke. Even if a 2 stroke is running perfect, the top end needs rebuild every 2-3k miles regardless?
 
4 strokes are more reliable for a cheap motor and last forever. 2 strokes run hotter and produce more power. The more expensive 2 strokes however may last very long and are certainly very reliable.

I like 2 strokes better for smaller CCs because they produce more power than 4 strokes.
4 strokes however may have more torque, but if you get a good 2 stroke engine like the dax gp 50, it should have torque thats better than 4 stroke 50cc engines.

Oh and the expensive quality Japanese made 2 strokes tend to last very long and are very reliable. Probably last longer than 4 strokes that are cheaper or just as long. The GP 50 might be reliable, although I can't comment on that because I've never owned one. It's a chinese clone of the KTM 50 motor (I don't remember correctly, but it's either Japanese or Italian made which is very top notch in power and reliability also. Both countries make quality motors, infact those expensive racing pocketbike motors like BLATA and POLINIs where 50cc can produce like 15 horse power are Italian and are very reliable.) which was used on branded dirt bikes and was very reliable. The KTM 50 is actually pretty much a Morini engine based on its looks. Morini is Italian and their 2 stroke engines last forever and produce a lot of power and torque. May even be able to pull wheelies, but you have to be carefull with your spokes or use the Manic Mechanic sprocket mount and do all you want with the power.
You get what you pay for.
 
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Small engines that produce high power are going to do it at high RPMs. Engines like this GP50 and the Morini have to be revved to way beyond annoying-the-neighbor levels to make their power. 3+HP per cubic inch requires that.

These engines are more suited to race application than daily stealth riding. Oh, and gera229, Morini is Italian, not Aussie.
 
So gera we all should concider you're input as uneducated. Not to be rude but it's input like that that's leading folks the wrong way on this site.
 
IreBo said:
So gera we all should concider you're input as uneducated. Not to be rude but it's input like that that's leading folks the wrong way on this site.
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@IreBo I did my research a while ago before posting.
You expect me to remember it perfectly since it was a while ago?
And I said "I do not remember correctly" lol so you can definitely assume I am not correct.

Also did my research on gearboxes, clutches, brands, engines all that stuff; so you can say that I am educated and do not mistake yourself with what you said about me being uneducated.

No one said there was anything misleading and no one said that my my post was wrong or off, other than the mistake where I misnamed a brand.
Otherwise if there is something else that's wrong in my post other than misnaming a brand, why not fix it and tell me what's wrong IreBo? Or do you not know because you don't know anything about what I said? No offense to you either. Just saying. :)

I've also had experience with a few engines both being 4 strokes and 2 strokes.
 
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I have decided that this will be my next engine, if I am ever able to come up with the money. My current bike is a Cranbrook. I have a 44T rear sprocket. I do believe my frame is steel (dont flame me for this) because I read somewhere that magnets dont stick to aluminum frames, and magnets stick to my frame, so I dont believe frame integrity should be an issue. I do want to know a couple things. with 26 inch rims, is a 44T rear too small? What size sprocket should I use? can I attach my HT throttle cable to this carburetor? I have a modded pocketbike pipe with a HT header, will that pipe fit on this engine? do I need to remove my pedals to use the kickstart? I am currently using universal 2 cycle air cooled synthetic oil, can I use that in this engine, or should I use some sort of high quality oil in this engine. Not going to spend $500+ on an engine and ruin it because I dont know how to take care of it.
 
motor_bike_fanatic said:
I have decided that this will be my next engine, if I am ever able to come up with the money. My current bike is a Cranbrook. I have a 44T rear sprocket. I do believe my frame is steel (dont flame me for this) because I read somewhere that magnets dont stick to aluminum frames, and magnets stick to my frame, so I dont believe frame integrity should be an issue. I do want to know a couple things. with 26 inch rims, is a 44T rear too small? What size sprocket should I use? can I attach my HT throttle cable to this carburetor? I have a modded pocketbike pipe with a HT header, will that pipe fit on this engine? do I need to remove my pedals to use the kickstart? I am currently using universal 2 cycle air cooled synthetic oil, can I use that in this engine, or should I use some sort of high quality oil in this engine. Not going to spend $500+ on an engine and ruin it because I dont know how to take care of it.
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do your self a favor...just dont. no personal offense.

Putting a 9hp motor on a cranbrook is a bad idea. Yes cranny are cheap thin-wall Chinese steel.
44t is too tall, itl be geared for something ridiculous like 70mph
No your Ht cable wont work
No your pipe wont work
You might need wide crankest depending on how you mount the motor, but its likely
No you cant use crappy oil
 
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motor_bike_fanatic said:
you are one disrespectful dude and thats all i got to say to you now good day sir
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im just being honest. its a bad idea, i think everyone will agree. Cranny + 9hp = certain death. Im just trying to save you the money, time, headache, and hospital bills.

Come on i even answered all your questions.

no hard feelins dude
 
well tbh I think the best answer in this case is probably the one I get from the dealer. He may say the same thing as you, he may not, either way if I ask him questions and he gives me advice and something still goes wrong, he has to honor the warranty. For two, all you did was tell me no I cant do this and no I cant do that, and didnt tell me what I should do instead, or even why I cant do certain things. I get the fact that my frame might not handle the power of this engine. with the gearing, do I want more teeth or less? more teeth means more torque, and I dont want to pop wheelies every time I hit the gas. If I modify my pipe to fit the gp exhaust tube, then can I use it? what throttle cable should I use instead of the HT cable? and seriously, how do you know my oil is crappy? I can tell you one thing. As far as synthetic 2 cycle air cooled oil goes, they are all pretty much the same, unless a certain engine requires special oil, such as very high rpm engines usually require racing oil, as universal oil doesnt have the proper lubricity for 10,000+ rpms. so, what kind of oil should I use?
 
motor_bike_fanatic said:
well tbh I think the best answer in this case is probably the one I get from the dealer. He may say the same thing as you, he may not, either way if I ask him questions and he gives me advice and something still goes wrong, he has to honor the warranty. For two, all you did was tell me no I cant do this and no I cant do that, and didnt tell me what I should do instead, or even why I cant do certain things. I get the fact that my frame might not handle the power of this engine. with the gearing, do I want more teeth or less? more teeth means more torque, and I dont want to pop wheelies every time I hit the gas. If I modify my pipe to fit the gp exhaust tube, then can I use it? what throttle cable should I use instead of the HT cable? and seriously, how do you know my oil is crappy? I can tell you one thing. As far as synthetic 2 cycle air cooled oil goes, they are all pretty much the same, unless a certain engine requires special oil, such as very high rpm engines usually require racing oil, as universal oil doesnt have the proper lubricity for 10,000+ rpms. so, what kind of oil should I use?
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Ok i see. Your right, im tired. il let mr.dax take it from here. my suggestion to you is to re-read this thread, some of your questions were answered in it.

such as the gearing, throttle cable, and pipe.

Universal 2 stoke oil sounds like something you buy at pepboys for a weedwacker. This a dirtbike motor that makes peak power at 9500 rpms, probably maxes out at 10-10500rpms. There is a specific requirement for the clutch oil so i assume there is specific requirement for the engine oil as well.
 
No offense motor_bike_fanatic, but I'm inclined to agree w/mobbin in general...

Even assuming the HT is a solid 2hp & this "gp50" is actually 9hp, we're talkin' about 4.5x the ponies... which given some crannies have been known for structural failures even w/just the HT (chainstay fracturing), has got to make you pause for a moment to consider the possibilities.

At "9hp" this isn't an engine I would recommend to anyone for general motorized bicycle use, aside from it's legality (assuming race/track) - you'll definitely need fabrication & welding tools & abilities to even mount it as it is not a "kit" in any way, let alone the potential reinforcement even a quality bicycle may need... this defo isn't something to consider if you're wanting a "budget build" as just about every part would have to be reviewed & considered for upgrade - rims, spokes, hubs, sprocket adapter, brakes, forks & bearings come to mind, and that's prolly somewhere between 500 & 1000 bucks in just bicycle components alone. An interesting example for perspective is just a replacement cylinder head for this engine costs the same as a brand new Huffy Cranbrook in it's entirety... well, the head is $4 cheaper, but still...

Please don't think I'm being dismissive or defeatist, it's just while $480 is a bit rich for a clone engine - if you're gonna spend that kind of cash on a motor for a bicycle, you might as well spend the money needed to make sure you've a bike that can take it, not only for your safety but to protect your investment... at the least, it'd be a real disappointment to get the thing going only to have it rip apart under you.

The least expensive bicycle I'd personally consider for a "racing" engine like this would be the Worksman Industrial Newsboy & even still, it'd be just a base platform pending modification for structural integrity & component upgrades & again, that requires both your pennies and welding capabilities... if you're interested in finding out more specific information regarding what's needed - I'd suggest checking out the Morini section & their 9-12hp creations to see what they've learned through their trials & tribulations - like spending 3-400 dollars on just a rear hub only to still have it fail...

Such are the costs of experimentation & racing ;)
 
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all synthetic air cooled 2 cycle oil is universal. Thats why all it says on the bottle is synthetic oil for use in ALL 2 cycle air cooled engines. says that on every bottle of oil I ever bought. says it on Pennzoil, says it on Lucas, says it on the no name brand I buy at walmart. thats how I figured out I could use walmart oil. I was using Lucas, but saw the walmart stuff at half the price and found out it was the same. Had this engine for a year and only used Lucas for the break-in. Im gonna clean my spark plug next weekend so I can do a proper color test, but so far I see no signs of this oil hurting my engine. But, if this engine goes up to 10,000, it probably needs racing oil. In all honesty, you turned me away from using this engine already. $500 for the engine alone, then I need a frame, a different throttle cable, a different sprocket, a different pipe, special oil. Probably talking up to $1,000 total on the build at least, plus the time involved in building a bike from scratch and dialing everything in, probably at least a week. I may as well just buy an old dual purpose dirtbike. Thanks.
 
Makes sense. Walmart oil in a Walmart bike. Just sayin'.

Don't get me wrong, I started with a Cranbrook, but quickly realized it was not a wise frame to continue with if I valued my body. It will fail with a 49cc 1.5hp motor. Throw a 9hp on? Not a chance. If I were you, I'd keep checking around on Craigslist and local garage sales and such for an older Schwinn frame. They're a bit longer, better steel, better welds and better geometry all around.

Now back on topic, what carb is included with this? Sorry if it was mentioned before.
 
Just received me GP50! THANKS DAX! Packaging was awesome, i was expecting a dirty oily motor, but this things looks damn near new! Gonna get her mounted up today! Woohoo!!
 
well i disagree with the tearing of spokes by a 9hp engine - liveforphysics has an electric mountain bike that does over 90mph...

we a elmoto experiment with the electric EV's and a electric motor has severe torque compared to a gas engine...

at present im building a 72 volt electric motorcycle and ive built several gas powered bicycles - you would be surprised how much punishment a bicycle can take...

all i ask is where can get one of these 9hp engines at???
 
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