How to get the best performance from a China engine? CARB???

[ETHANSFBIKES]

I just purchased a Chinese made engine kit (80cc) and I was wondering if anybody has some secrets on how to get these to really rip? I did install it completely stock except for a modified air filter. If you have any tips or tricks or parts I should buy please say.
Thanks
Here is the site I bought it from: http://www.motovelo.us/

[Ratfink1962]

one thought...

[chevelle68]

The guy you purchased it from claims to have the best and fastest motor kits around. Did you ask him about performance mods? I have a few fast ones but its hit and miss with these china dolls. Post a picture of you bike...

Wolfman

[SectionEightLife]

Well, they make several mods for the motor, most of which are pretty much all about bring out the subtle efficiencies of the motor rather than 'SoUpInG It Up!!!!' The top dogs though are aftermarket exhaust pipes, 'boost' tubes, which really just manages back pressure for the engine, and the biggest winner in my book are the hub clamp style rear sprocket mounts. They pretty much eliminate wobble from the rear sprocket reducing vibration and allowing everything to run MUCH smoother. Now that's all stuff to make your engine run better and stronger not necessarily faster though. However, there are things that will allow you to boogy if you need really need to haul the mail. They do in fact sell mini nitrous kits for the motor, (I mean common, someone had to, how can you resist applying some liquid torque ), also the BEST bet would be to get yourself the a hub clamp mount and buy one of the smaller aftermarket rear sprockets that go to them. Keep in mind that changing the gear ratio like this will bring you closer to an overdrive and increase your MPH but kill your torque. So you'll go faster when you get going, but will have an easier time bogging at the start (soo, just pedal more when you start off ) Changing the gears alone gets things REAL hair really fast. Another way to do this would be buy a Jackshaft and drive a derailleur through all its gears. But then you just have a 6-speed moped cause you can't pedal

[SectionEightLife]

Oh and as far as tricks for the little buggers, I'm starting to realize that if you have a welder go ahead and make your own mounts for the motor. The motor doesn't have to be permanently FIXED to the bike, but go ahead and weld the mounts right the heck to the frame. Cause even with the high end super duper reinforced motors those nonense clamp on 'grip the frame till you turn me on then I'll come loose and strip the paint off your bike' style mounts just ...suck. lol

[ETHANSFBIKES]

Thanks for all the awesome info everybody... Here are soem pictures of the bike:













Ill admit that it is a little ugly at the minute. I have a much cooler frame and plans in my head
The only modification I have made is to the stock air filter, as you can see.

Here is the cool frame:



Smelly gas can for the win :



Enough for tonight...

[SectionEightLife]

Yeah they typically arent the best looking motors right off the bat, but I like yours. Yours looks like it'd be a bit more functional than others too.

Oh, and one other thing I forgot, The tensioners on these motors are just the worst. Bike guys first start these off and don't realize that the amount of power put into taking up the slack from the motor is a lot more than what it'd seem. So the tensioner gets hammered till it starts to spin a bit, gets just out of line enough where the leverage of the next time goes taught pulls it right out of line, stripping the heck out of your paint and even the metal, and throws the tensioner dead into your spokes. Bends 'em up real bad and and stops 'em dead cold (which might bend you up too ) Also, if it doesn't hit the spoke the chain likes to come off, wrap around your hub at 500mph and snap even the 'stronger' aftermarket chains like twigs.

Good fix would be try to fix the tensioner permanently to the frame (weld) and then another personal must that I do for ALL my bikes is go down to Tractor Supply and buy yourself a box of good 'ol No. 41 chain. Farmers don't play around. Its thick, beefy, and if you break it they give you a medal. Its alooott bigger chain but it'll fit fine and make your bike look like it can take a punch

[Wolf's Den Garage]

Puch Hi-compression head, Dellorto carb, port match intake/exhaust, polish exhaust header, expansion chamber, NGK plug/wire, trim intake side of piston skirt, #41 chain, hub adapter.

[SectionEightLife]

OH I FORGOT ALL ABOUT THE PUCH HEADS!!! Those things are actually pretty gnarly!

[ETHANSFBIKES]

Puch Hi-compression head, Dellorto carb, port match intake/exhaust, polish exhaust header, expansion chamber, NGK plug/wire, trim intake side of piston skirt, #41 chain, hub adapter.

Sweet thanks! I think I can get a puch head and a lot of the parts at an awesome moped store in my area: [url]Treatland.tv[/url]
More specifically: https://www.treatland.tv/moped-kits-s/55.htm?searching=Y&sort=5&cat=55&show=50&page=1&search=%20high%20compression

Thanks for all the info everybody.

[Wolf's Den Garage]

Yup. That's the place. I'll be putting my 50cc head back on my 66cc this spring. Currently have the 70 on. More squeeze with the 50.

[ETHANSFBIKES]

Wait... what size head should I use with my "80cc" engine?

[SectionEightLife]

Wait... what size head should I use with my "80cc" engine?

Well your 80cc is technically a 66c, its just a difference in the way they measure the cylinder, the western hemisphere does it the right way of course and therefor if we talk about a 66cc its really your "80". And I believe that you go for either the 70 hi hi or the 50 hi hi (I think, its either the hi hi or the hi) but the 50 has a much higher compression, which means more thumpin' - its a touch harder to turn over though lol...

[ETHANSFBIKES]

Cool thanks. I had an epic wrestling match with the frickin' chain tensioner were many mean words were exchainged and now it lies in a mangled heap on the garage floor. IF YOU BUY ONE OF THESES KITS GET RID OF THE CHAIN TENSIONER OF BUILD YOUR OWN!! The bike has horizontal drop outs so I got the chain to the right length. It is AMAZING how much faster it runs without that stupid thing. Im serious, It feels so much better. Pics...







Almost forgot: Super high quality italian petcock with spring loaded position switch as opposed to friction chinese POS. It has three setting, open, closed, and reserve!



Also, is it normal for my pipe to drip oil? Not a lot just a little puddle.
Thanks

[SectionEightLife]

Eh, Ive had a touch of drippage with mine, and what'd I tell ya about those tensioners?