newbie here with 1st build questions

[ez dave]

i ran a 66/80 with an expansion chamber jetted carb and a 36 tooth sprocket and would see 45 mph. i live in florida with relatively few hills. im also 240lbs so these gains were impressive. as far as internal motor work i'd stay away until the time comes to tear it down anyway, you know the old saying if it aint broke.

 

[ez dave]

i had the sbp chamber and it does work well, though a little pricey.

 

[dotcom]

question- would a 32 tooth sprocket be better that the stock china kind that comes in those kits? If so, why and would it do harm to the engine as well as make the bike faster

 

[V 35]

In the interest of safety, consider this ... A Pineapple Joint sprocket [ comes with kit ] only supplies torque to one side of the wheel,
a ' real ' motorcycle supplies torque evenly, to all spokes . A wheel that only sees one side torqued, will warp. The China Girl kit sprocket is poorly made, same with the chain. If you value safety, and reliability, upgrade to a 2 piece hub sprocket, and a better grade of chain .
BMX chain works well with many sprockets. As for sprocket size, the big sprockets make for good off the line punch. The 36 tooth ' powerbands at about 6 MPH up making it a useful bike. I've got a 42 tooth, slow [ 25 MPH ] but climbs hills . A local guy has a 24 tooth rear sprocket, his bike doesn't powerband until 20 MPH, can do over 50 MPH, and can't climb a gentle slope

 

[dotcom]

which would perform better?
1: 80cc china kit
2: harbor freight 79cc engine kit?

 

[V 35]

What are you asking ? An 80cc engine kit is the raw basics. A better chain / Hub / sprocket is highly recommended

Harbor Freight 79cc engine kit ? .... Tell us more ! Sounds like your trying to compare a raw engine to a complete kit.

Also, are we talking frame mount, or rack mount ? The more you tell us, the better we can help.

 

[dotcom]

harbor freight 79cc engine with rack mount or frame mount versus an 80cc china kit from ebay
Which would perform better?

 

[V 35]

Any motorcycle chain lube will do it. Some riders like 90wt gear oil, drip a few drops on chain after a ride . WD 40 is more of a cleaner than a chain lube, ok for pedal chain, wimpy for powered chain.

 

[Fabian]

Automatic transmission fluid (ATF) works well as chain lube (in a clean riding environment), plus it has a detergent infused into the oil, making it easier to clean the chain by simply adding a little more ATF on the chain.

For more serious riding in a dirty environment, i mix 30% Molybdenum Disulfide grease in with 20% ATF and 50% Mineral Turpentine. Mix it all together in a bottle and shake vigorously till the grease has dissolved into the ATF and Turps.
Apply this mixture to the chain and hand crank the pedals so the lube nicely covers the rollers and soaks into the pins. By the morning the turps will have evaporated, leaving a good coating of grease and oil on the internal surfaces of the chain as well as the outside of the chain rollers.
This method prevents lube flying off the chain; keeping the lube where it should be, and it keeps the bike frame a lot cleaner. The downside is that when dust mixes with the grease, it forms a filthy black paste that is horrible to try and clean; not only just the chain but your hands and fingers; getting under your finger nails, staining them black for the next 3 weeks.