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Old 07-06-2008, 10:40 AM
thatsdax thatsdax is offline
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Default china bicycle motor facts...

There are at least 50 different factories in Asia that make the 2 stroke engines. Although they may look the same, they are different. Much different. Since I have bought and tested many of these engines and been in the business of selling engines and their applications for around 35 years all over the world, and used them and applied them both diesels and gas engines in many countries around the world. And this continues. Actually it continues at an increased pace these days. I do not know everything about engines, but I do know some things, and I will expound on these things I do know. And this I know, Those that say these 2 stroke engines from Asia all come from the same factory or factories do not know what they are talking about. There are many many differences in both design and quality. Since the similar items are fewer, it is easier to tell of these similarities than the differences since the differences are many. Keep in mind, even those items that are similar, they too are actually different but similar enough to be interchanged and will actually function on an engine from another factory. These items are as follows, side covers, magneto, CDI, Spark plug, wire and cap, carb, exhaust pipe. Throttle and cable, Clutch lever, . Those are the only items that I am confident can be used with other kits. Now.. Out of those list of items, they are all different but can be used with other kits with better or poorer results depending on the type and size of engine made and from what factory. Out of those items listed, the spark plug would be the only exacting item made. The LD4Z plug. That seems to be the same for all kits.

As for the 4 stroke kits, Asia has a range of 4 strokes that are top shelf. The 4 stroke IC motors are typical in China and are all top shelf. You can not compare the 2 stroke bike kit motors to the 4 Stroke IC motors. You just can not compare. You also can not compare the 2 stroke IC motors to the non IC 2 stroke motors. There is just is no comparison. You can not do it. The 2 stroke IC motors from china also cost 2 times as much. As for fit and finish, the Japanese IC motors still have it. But as for reliability, they are not better. And.. I can tell you, the China 4 stroke IC motors Fit and finish will improve and I am confindent they will be on top in the next couple of years. As a matter of fact, China has now moved to the top in world wide production of small engines and scooters. Japan has now moved into many of the China factories investing heavy in QC and engineering investment. USA has done the same.

To sum this up, I am defending what I know to be true. I am not defending China, USA, Japan or Europe and their methods and investments. I only want people to know the facts . When someone is saying things I know to be false, I can not sit idle by and let it happen. I have to speak up. It was once reported in this forum that Factory and manufacture Involvement is appreciated. As a USA Manufacture, Supplier, and also a Vendor, these are a few of the facts as I know them. No Drama, just facts. I do not appreciate those that express their views disguised as axioms. Thanks.. And Enjoy the ride...
Old 07-06-2008, 11:01 AM
Bikeguy Joe Bikeguy Joe is offline
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Default Re: Here are some facts...

Thank you!
Old 07-06-2008, 03:22 PM
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Dave31 Dave31 is offline
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Default Re: Here are some facts...

Thank's Duane for that info
Old 07-06-2008, 06:37 PM
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deacon deacon is offline
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Default Re: Here are some facts...

So does that mean that all the guys on ebay who say they have the best kit really do?
My posts have entertainment value only. A bike ain't yours till it has your blood on it. Then it owns you.
Old 07-06-2008, 08:40 PM
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Pablo Pablo is offline
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Default Re: Here are some facts...

I can tell there are different engine makers by the castings....and something silly like some factories use 8mmX1.00mm head studs others use 8mmX1.25 studs.

Allow me to ask this:

Are there more than 2 carb factories? I've only seem 2 close twins.

ALL The supposed 80 cc engine that really is 67cc or whatever - do they actually have different bore and stroke?
Old 07-07-2008, 01:10 AM
thatsdax thatsdax is offline
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Default Re: Here are some facts...

Yes.. I have found at least 4 different versions of carbs. Slide size, slide type, and with different type bowls. All seem to use the same style white donut float. As for Size, the largest I have found is around 69cc. That is.. If you count the complete stroke distance. Which technically for a port valving 2 stroke is not its true displacement. But if you do, you can get 63cc to 69 cc displacement. If not, you get anywhere from 42 to 45 cc displacement depending on port size and style. So.. Technically, you can get anywhere from around 30cc all the way to 69cc depending on the math and engine type. Keep in mind, these do not account for all the engines like these that come out of Asia. Only the ones I have seen . I have done searches and asked other manufactures and so far, have never ever seen a true 80cc or anything close to it. Which gets me since I see so many selling engines as 80cc. I was told that there is no 80cc no matter how you measure. And.. Really, there is no need for one. The Current 50's and 70's are plenty fast enough for any bicycle. Anything less than 50cc is legal in most states. So try and stick to the 50's. They cost a little less and are legal most places. Enjoy the ride..

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