A warning to those looking to mod their motorized bicycles:

Most, if not all, of the hacks and mods featured on this site were made by individual hobbyists. If you are new to working with 2-stroke bicycle engines, please by aware that there's a possibility that a mod featured on this site could seriously damage your engine. Please don't try any mod from this or any other site unless you fully understand what you are doing. The owner of this blog will not be held responsible for both material and bodily damage caused by performing a modification featured on this blog. Also remember that opening up your engine may void your warranty!

Sunday, October 30, 2011

Extra muffler silencer

Well, that's one way of doing it!  I honestly don't think the stock engines are really that loud, but if you really need to make her quieter, this is another(albeit ugly) way!

Monday, October 24, 2011

Cleaning up your electrical

If you have come across other pictures of my bike, you'd have seen my electric wires hanging out and simply clamped to the bike with zip ties.  These 2-stroke kits pretty much just have the electrical connections hanging out and I really hate that.  Also, I chose to zip-tie my CDI instead of using bolts(since it's plastic and apparently breaks easily), but that caused the CDI to move around and the plug wire would often be hanging out the side. 

Well recently, some guy was tailgating me and I made a sharp right turn and, well, I wiped out.  Got some road rash, but at least I got the opportunity to revise my set up!  I wanted something both visually and practically superior, so this is what I came up with:

  • I moved my CDI to the top bar on my frame.  That way it won't slide much even if you zip-tie it.  For some reason I just think it reduces clutter that way instead of having all the wires smashed up on the one bar on the bottom.
  • Shrink tubing: People say to solder the wires and use electrical tape.  I decided to go with something nicer looking and less sticky.  You can get shrink tubing at Radio Shack or anywhere that sells electronics supplies.  Just cut a piece, slide it over the bare area on the wire and roll a soldering iron over it to make the tubing shrink.  A heat gun may work well too.  It looks great and creates a nice seal to prevent shortage.
  • I took all the wires, including the ones coming from the kill switch, and ran them through a piece of flexible cable tube that I cut out.  This looks MUCH better than having all the wires visibly hanging out.  You can buy cable tubing from Radio Shack or Wal-Mart.  Then I just zip-tied the tube to the bottom frame. 
  • Used silicone sealant on the CDI(where the plug wire comes out) and where the magneto wires come out of the motor.  This in combination with the shrink tubing and cable tube should make this setup really water resistant.
P.S. Yes, I know that some paint is missing on my bike.  That's due to B-12 Chemtool and the fact that I spray-painted my frame.  One of the next things I plan on doing is patching those areas.

This post is sponsored by B-12 Chemtool: The world's most powerful paint-thinner!

Tuesday, October 18, 2011

Soda can head gasket

Sorry, I don't have any actual photos because the camera I used got jacked up and the photos were lost. :(

You don't need to spend money to replace your head gasket!  If the one you have is in mostly okay shape, you can cut your own from an aluminum soda can!

Simply cut a large piece of metal off a soda can.  Notice how it still retains the shape of the can?  There's an easy way to flatten out the metal; take a clothes iron and iron it as flat as you can.  It won't be completely flat, but you can get it flat enough to be useable.

If this doesn't make sense, the first part of this video shows how this is done.

Once you have made a nice piece of flat aluminum, trace your old head gasket on it with a permanent marker.  Then simply cut out your new gasket with a razor blade or an exacto knife.  Most of it is simple to cut, but the stud holes can be difficult; the key is to try cutting them a little larger than you'd think you'd need.

When you have placed your new head gasket on your engine and placed the head back on, push your bike forward with the clutch engaged to make the piston move.  If there are any air leaks, you should hear(and feel) the air come out around part of the head.  This is very important to check for because air leaks are very bad for your engine.  The first soda can gasket I made had too much cut off from the center and that's where an air leak came from.  I did a better job on my second soda can gasket, and so far there are no leaks.  If you want, you can use Copper Kote to create a better seal.

Are there any advantages to a soda can head gasket?  Other than costing virtually nothing, soda can metal is much thinner than the stock head gaskets, so if you're looking for both a quick fix and less compression, a soda can head gasket might be the way to go.

$5 solid tensioner mount

There are plenty of tensioner mods involving a spring, but sometimes people have issues with a spring-loaded setup.

This mod will give you a tensioner that is both solidly mounted and one that definitely won't fall into the spokes!

Saturday, October 15, 2011

Backwards cylinder jug

Isn't it strange how the stock engines have the intake on the rear and the exhaust in the front?  Of course the reason for this is to make these kits easy to install on most bikes.  But if you want a more logical approach to running your engine, it is possible to turn around your cyclinder jug so that the exhaust is in the rear and your carburetor in the front.  If you're looking to increase intake flow and to get the smelly exhaust behind you, then this might be a good mod for you.

Before you go spinning your jug around, please keep in mind that you have to do a few more changes in order to make your engine run properly with this setup.  Read more to learn what to do!

Candlestick velocity stack

A velocity stack eases the flow of air into the carburetor.  Wikipedia says that a velocity stack for an engine does two things:
  1. Allow smooth and even entry of air at high velocities into the intake tract with the flow stream adhering to the pipe walls.
  2. Modify the dynamic tuning range of the intake tract by functioning as a resonating pipe which can adjust the frequency of pressure pulses, based on its length, within the tract.
In other words, it works like this:

Instead of permanently polishing out the NT carb intake like others done, you can get a similar effect by having a velocity stack.  Bairdco made one out of a candle holder from a swap meet.