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Skinnypartdeux

New Member
Jan 26, 2013
16
0
0
Louisiana
Hey guys! My friends call me Skinny, I live in north louisiana. I used to have a Honda Shadow 750, had to sell it when I moved back from SoCal. People around here aren't quite as aware of motorcycle, but I needed to be on two wheels! I started looking into MBs 2 years or so ago, then my daughter was born. A few months ago a coworker got a kit for his bike, and the interest was peaked once again! I got my kit at the end of december (xmas present for myself!) I've been running it for about 3 weeks now, finally getting a taste of post-break-in performance! It's still not broken in completely yet, but it is running good. I got the basic 80cc/66cc kit from bikeberry. I'm just wondering what I can do to get optimal performance. I'm running the NT carb. I guess what I'm asking here is for advice on: spark plugs, fuel ratio and aftermarket parts. Not looking to go more than 35mph, but I want better low end speed, or what I like to refer to as more get up! As well as just a smooth running, long lasting motor. I've been lurking around here since before I got my motor, so I've learned alot thanks to 2door and the others, just looking for more user specific answers to my questions. Any and all help is appreciated!

**EDIT-ADDING PICTURES**
I can't figure out how to add them on this thread, but you can check out my album on my profile to see pics of my bobber build.
 
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2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
From one 'skinny' to another, welcome to the forum. We're glad you've benefited from the information available here and advoided some of the problems that can be had with a first time build.

35mph isn't an unreasonable expectation. It is pushing the top for a stock engine and low gears. A 40 tooth sprocket, even a 36T if you don't have big hills, will help as well as proper carburetor tuning. You'll want to gap your plug to about .024 for starters and run a good fuel/oil mix, something in the 32:1 to 40:1 unless you go with one of the exotic/synthetic oils which require much less; 50 or even 100:1.

Watch your spark plug color and shoot for a nice brown. Explore some of the expansion chamber exhausts but you'll also have to re-tune the fuel/air mix using them. Also be aware that the Chinese 2 stroke engine perform better and better as they accrue miles. They're somewhat slow to break in and the more miles you put on them the better they'll perform.

That said, please concentrate on the bike before worring too much about speed. Brakes, bearings and frame integrity are critical.
Have fun and ride safe.

Tom
 

biknut

Well-Known Member
Sep 28, 2010
6,631
409
83
Dallas
Hi Skinny, welcome to the forum from Dallas.

As usual Tom's advise is golden. I'll just elaborate a little on some of his comments. An important thing to know about oil ratio, is follow the oil manufacturers recommendation. Most dino based oil will be about 32:1. Synthetic is usually 40:1 - 50:1 and up.

The best modification I did to improve bottom end was to add a expansion chamber from SBP. Varying the length of the header changes where the power band is strongest. The longer the header pipe, the lower in the power band were the expansion chamber starts working.

A Speed carb is a good investment for smoother idle, and less 4 stroking. It uses the same throttle cable, and tuning is close to the same.

A good spark plug is a NGK B6HS, and sometimes a NGK BP6HS, which is extended tip. It's a good idea to buy your own spark plug wire, and cap at a auto, or motorcycle supply.

I assume it's about as flat where you live as around here, so I would recommend a 36T rear sprocket. With that gearing on 26" wheels you'll be able to cruise 35 mph for extended periods without over revving you motor.

You're probably going to want to buy a 66, and 68 jet. I run 66. Stock kit jet is about a 70.

Keep a close eye on all your nuts and bolts until you figure out what's most likely to fail or come loose. Especially keep an eye on your head bolt torque. The head bolts need
to be re torque 4 or 5 times in the first 600 miles or so. After that not so often. Be aware the acorn head bolts sometimes bottom out on the cylinder studs. It's a good idea to check them for clearance, and if necessary add washers under the acorns, or change them to open nuts. Most people torque the head bolts to 125-145 inch lbs. I use 125 in lb.

Hope you bike runs well for thousands of miles.
 

Skinnypartdeux

New Member
Jan 26, 2013
16
0
0
Louisiana
Thanks for the tips guys! I put about 30 miles on it today, just cruising around town here and there. And yes biknut, it's about as hilly here as the salt flats! Lol the first gallon of gas I mixed was at the recommended 16:1, I know everyone says that it's too rich a mixture, but I'm getting the same performance if not better than buddy's bike that is broken in and running 50:1 synthetic. I've mixed the second gallon at 24:1. I'll keep you posted on performance once I get through the 16:1. I'll look at getting one of the spark plugs you mentioned this week. I'm doing kind of a "bobber" build, 26" flat black beach cruiser with flat white accents, 25" ape hangers (black, of course) and .50 caliber ammo boxes for saddle bags, I want to put a 24" rear wheel on it, to give it more of a "thrown" stance, I know that I'll lose top end by doing this, but could I still achieve 35mph by using a smaller sprocket? I'll post pictures tomorrow when I get to a computer, using my phone right now.
 

Skinnypartdeux

New Member
Jan 26, 2013
16
0
0
Louisiana
The reason I keep at it with 35 is because that's the highest speedlimit I come across on any of my routes. I just want to be able to keep up with flow of traffic. Thanks again for all of the help!
 

wheelbender6

Well-Known Member
Sep 4, 2008
4,059
221
63
TX
Welcome to the forum. I've had my motorbike since 2008 and I'm still changing stuff. I fiddled with my suspension seat for a year or so until it worked to my satisfaction. Fiddled with clutch adjustment until I intalled a centrifugal one. I'm currently fiddling with my bullet headlight; hopping it up to make it brighter.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
Hey, I think I've seen that helmet somewhere. :)

Now that's what I call 'ape hangers'. Good job, Skinny. Thanks for sharing with us.
Have fun and ride safe.

Tom