Performance and dependability help.

[Beau rapoza]

I'm on my third build. And besides changing hardware fuel lines and spark plug, I haven't used any other mods. I was wondering what I should put on my bike to get more off the line power. And make it more dependable. Any ideas would be greatly appreciated. I have a 66 80 seeutek
China girl. With stock pipe carb and head. I've locktited and double nutted most everything.

 

[HumanPerson]

Take the carb and exhaust off and clean up the ports if you're able. Check the cylinder transfer ports for burrs to. SBP expansion chamber next http://sickbikeparts.com/expansion-chamber-black-exhaust-pipe/
Upgrade to a slide carb insted of the stock NT carb, personal preference really. (RT or RunTong SHA Clone Carb)

Fred Head. http://shop.crmachine.com/category....CF47ED29130E2701.p3plqscsfapp001?categoryId=5

Just a start to your never ending cash cow

Keep it simple, ONE upgrade at a time for a tank full and see how it all melds together into a nice running everyday cruiser

 

[Beau rapoza]

Awesome thanks. What are the transfer ports. Do u mean the intake and exhaust ports on the barrell.?

 

[HumanPerson]

I work with numbers and i know this isn't rocket science but i really get confused when things co wrong with these engines, and they do quite often lol
Keep it simple and ask questions here.

 

[HumanPerson]

There are TRANSFER ports inside of your cylinder. The INTAKE and EXHAUST ports that your intake manifold and exhaust bolt to are readily available to modify from the outside of the cylinder and the inside, but be careful, know what you're doing or one or two millimeters can mess you engine up.
Search this forum. There are alot of useful things to put under your hat for future reference.
I'm just an everyday rider that rides these things like i stole them
Cheap disposable engines that create alot of fun and can be reliable if properly taken care of.

 

[Beau rapoza]

Nice. Thanks for the advise. I'll YouTube a vid of the transfer ports...

 

[HumanPerson]

motorized bicycle transfer ports

YouTube that

 

[Timbone]

Upgrade the rear wheel. SAS Halo rim is what I suggest. Put good quality bearings, sealed if possible, on the back axle.

Buy or fabricate some chain tugs to lock the rear axle into position.

Use a muffler clamp to lock down the front of motor to the downtube.

Secure the muffler, stock or expansion chamber, to the frame at multiple points.

Buy a sprocket adapter and lock your rear sprocket to the rear hub!

Carry: wrenches, screw drivers, Allen keys, master links. Prevent disaster!

 

[Potato_In_Exhaust]

You can also sand your head down some for added compression. You need something flat like glass sheet and sandpaper.

 

[Frankenstein]

Off the line power would be a jackshaft, higher speeds also can be gotten from a jackshaft. You can also gain dependability by lowering the speeds you need from the engine. You don't need to up the compression, in fact that will lower the dependability as you put more stress on the engine by doing so.

If you jackshaft you can lower the compression a tad, and run richer for better torque. You'll make the motor last far longer by keeping it in lower rpm, and riching it up enough that it 4 strokes at wot will keep it cool enough to last.

Use a good synthetic oil since it will smoke less.

You'll get a long time from a motor doing it like that, and you'll have the power you need when you need it.