III lost(click on the parts tab for black friday deals! 
Motorized Bike General Information, Maintenance and Troubleshooting
Tech Support Weds, Sat, Sun (855) 400-JAKE  ext.2

Below you will find basic questions and answers to motorbike related stuff. The questions we mostly get when we answer the phone. Maybe this will help you get acquainted before you call, and also can help once you've purchased and/or built a bike. safe riding! and due to bike building, we rarely answer. its a time thing...

Here is an instruction manuel some folks like:

"I got it the day after you shipped it. I love it. Thank you for building this for me! I got it together in about 45 minutes, and it runs great. Way better than my last bike."
– Zachary Bloom, the stars and pipes bike

What the Hell ARE these things?! Motorcycles? Bicycles? mopeds? scooters?!
Fear not, the answer is surprisingly dry and simple: showcasing the creativity of the dept. of motor vehicles, these are "motor assisted bicycles". the catch is, they have pedals; so we go with "motorized bicycles"

How long have they been around, you ask?

     Harley Davidson Made a motorized bicycle in 1903, and they called it a "motor-cycle". As with anything, modifications were immediate, and the frame became larger, stronger. The wheels became smaller and thicker, the idea of suspension was introduced. the suspension made stronger, more durable. As years passed, the pedals became stationary, and gears were introduced, etc, etc...The evolutuion of the motorcycle was iin full swing.
        In the '50's there was a resurgence of the lightweight motorcycle, or motorized bicycle. ( Harley-Davidson., Indian, and others had long since grown to bigger heavier, "motorcycles" since 1903) and the lightweight powered  2 wheeled vehicle came back in the form of a motorized bicycle called a "whizzer". The whizzer became quite popular and had great success for many years until the Laws and other factors took them out of fashion with the mainstream public. Whizzer engines are now a sought after commodity, and have never fully disappeared.
Where have they been?
As far as we can tell, it was in 2008 that the motorized bicycle was resurrected. the MB forum (motorbicycling.com) went online in 2009, and slowly but steadily these bikes have been gaining popularity. Some folks are even racing them, including us. Check motorbicycling.com for race information. 

The races are more of an excuse to get together and see everyone's custom bikes, talk bikes, have a few cold ones, and get in some riding without stop lights, roller-bladers, or police.

These motored bikes are a GREAT way to get around town without sitting in traffic, and they don't kill your wallet. Riding at 30mph, they are a great alternative transport that is sweeping the nation. As gas prices approach $5.00 per gallon, it's time for a motorbike. just think, that's $1.50 to fill this tank, and 3x the mpg of a prius.

FAQ # 1:"can I still ride it like a bike?"

You'll still be able to pedal the bike and ride like normal. Then, When you feel the need, you start the engine by releasing the clutch lever. it's that simple. You can stop or start the engine as you ride. Twist grip hand throttle (like a motorcycle) controls speeds from 15 - 35mph. The engine drives a sprocket on the left side of the rear wheel hub, which creates a totally independent drive sprocket and chain on the left side, that does not interfere with your human power drive chain on the right side.

FAQ #2: "are these things legal?"

Yes. They are considered a "power assisted bicycle", and you must obey basic traffic laws and wear a helmet. In CA for example, A rider must be at least 15.5 years old with a learners permit, or:

California DMV website states:
What is a moped or motorized bicycle?
  • There are two types of motorized bicycles, defined in the California Vehicle Code (VC) Sections 406(a) and 406(b).
  • Section 406(a) VC refers to a moped or motorized bicycle as any two or three wheeled device having fully operative pedals for propulsion by human power, or having no pedals if powered solely by electrical energy, has an automatic transmission, and a motor which produces less than 2 gross brake horespower and is capable of propelling the device at a maximum speed of not more than 30 miles per hour on level ground.

Motorized Bicycle (Section 406(b) VC)

  • Driver's License not required but rider must be at least 16 years of age.

So there it is, the long and the short of it. Time for some fun. and ladies ride em too! in fact a lot of riders are women. if you're a gal (or a guy thinking about getting one for your special gal)  a motorized bicycle is not out of the question, and very easy to ride if you can ride a bike.

F.A.Q. 3 :
        "how long do these engines last?"
We have heard of engines lasting for years, and seen them last 2 laps on a track. The more high performance mods are made, the shorter the life. "the bright burnung candle lasts 1/2 as long" theory. These engines are ridiculously affordable compared to a motorcycle or car, and easily replaced. Think about it:  If an engine blows up, replacing it is less than a tune-up for your car.

JakeBike. 30mph on 150mpg.
Hand made to-order. We custom build motorized bicycles specifically for you. We work with you to design the perfectly tailored ride for your wants, needs, desires. we'll get you  on the road to gas savings in style with our fuel efficient vehicles! you cant beat that with a stick! these bikes are just way cooler then a bland economy car. they punctuate who you are.

Only the best customer service and support. any questions you have will be answered within a day. After your purchase we're  always available to answer questions, and work is warranted  6 months. engines 90 days.

Motored Bikes are one of a kind, and an extension of the owner. the more you personalize your bike, the more it becomes an extension of who you are, and how you roll!

E-mail jake@jakebike.com
with additional questions. We check E-mail Daily, but are rarely able to answer the phone due to the busy shop. Apologies. this is also about to change very soon coming for 2014 we will have a new call service operator system

Motorized bicycles are not a replacement for a car or motorcycle. They are a vehicle from a bygone era. they are what the motorcycle was in 1910. They require regular tightening of nuts and bolts, as well as parts lubrication. Lubricating the chains and greasing gears and bearings is a regular part of MB ownership. Back in the day, women rarely drove because of a lack of power steering, and cars had to be cranked to start. They were brutish machines that required gloves and tools. These bikes are from that era, with a little more moderno. If you are not a machanically inclined person, this may not be the vehicle for you. We also do not offer a refund if you cannot get it started. You must read the information, do the research on motorbicycling.com, and do the work. We will help you, but not those who throw attitude. Although,  If you live in the los Angeles area we offer a service plan to our customers who choose not to "wrench" on their bikes. Basic Mechanical knowledge is required to own a "jakebike", *NEW POLICY- due to recent events, we reserve the right to determine if a customer is suitable for ownership. If you feel that you are not mechanically inclined, perhaps try a motorcycle.
       When you order a bike, or want a refund, I will ask "what is the password?". it is TigerTiger. this will let me know you have read the above material. Especially if you call me 3 days after receiving it wanting a refund because you cant get it started. PAH!

This is "Homer". Homer was jakes first motorbike. Homer went through many incarnations and experimentations before finding his new home with Jason P. We hear that Homer broke his seat tube and is now reclining in a living room in Whittier. We hope to have Homer join us in the window of our new retail location in Santa Monica, Ca.. Homer is currently in "Board track" attire, seen on the gallery page. :)

2.4 MB

                                                                    I got my kit, now what?! 
Click the above file for a complete printable tutorial instruction manual from the factory!

Why 2 stroke engines Need an Expansion Chamber
(added option on jakebike)

$125 version  $150 & $400 versions
The 2 stroke engine is a very simple design, and has 3 major components. intake, combustion chamber, exhaust. In 4 stroke engines, the exhaust pipes basically direct spent gasses away from the engine and vehicle. In 2 stroke engines, the exhaust is the 3rd point in the triangle of the power production process and should not be over looked!
Here is a great article written by Eric Murray, of motorcycle.com. READ THIS!:

You know that changing the exhaust pipes on your two-stroke motorcycle can have a marked effect on the engine's power characteristics, but do you know why?

Simply put, it's because the two-stroke exhaust system, commonly referred to as an 'expansion chamber' uses pressure waves emanating from the combustion chamber to effectively supercharge your cylinder.

In reality, expansion chambers are built to harness sound waves (created in the combustion process) to first suck the cylinder clean of spent gasses--and in the process, drawing fresh air/gas mixture (known as 'charge') into the chamber itself--and then stuff all the charge back into the cylinder, filling it to greater pressures than could be achieved by simply venting the exhaust port into the open atmosphere. This phenomenon was first discovered in the 1950s by Walter Kaaden, who was working at the East German company MZ. Kaaden understood that there was power in the sound waves coming from the exhaust system, and opened up a whole new field in two-stroke theory and tuning.

An engine's exhaust port can be thought of as a sound generator.

Each time the piston uncovers the exhaust port (which is cut into the side of the cylinder in two-strokes), the pulse of exhaust gases rushing out the port creates a positive pressure wave which radiates from the exhaust port. The sound will be be the same frequency as the engine is turning, that is, an engine turning at 8000 rpms generates an exhaust sound at 8000 rpms or 133 cycles a second--hence, an expansion chamber's total length is decided by the rpm the engine will reach, not displacement. Indeed, the only advantage to this crude pipe system was that it was easy to tune: You simply started with a long pipe and started cutting it off until the motor ran best at the engine speed you wanted. Of course those waves don't radiate in all directions since there's a pipe attached to the port. Early two strokes had straight pipes, a simple length of tube attached to the exhaust port. This created a single "negative" wave that helped suck spent exhaust gases out of the cylinder. And since sound waves that start at the end of the pipe travel to the other end at the speed of sound, there was only a small rpm range where the negative wave's return would reach the exhaust port at a useful time: At too low of an rpm, the wave would return too soon, bouncing back out the port. And at too high of an rpm, the piston would have traveled up the cylinder far enough to close the exhaust port, again doing no good.

Indeed, the only advantage to this crude pipe system was that it was easy to tune: You simply started with a long pipe and started cutting it off until the motor ran best at the engine speed you wanted.

So after analyzing this cut-off straight-pipe exhaust system, tuners realized two things: First, that pressure waves could be created to help pull spent gasses out of the cylinder, and second, that the speed of these waves is more or less constant, though it's affected slightly by the temperature of the air. Higher temperatures mean that the air molecules have more energy and move faster, so sound waves move faster when the air is warmer.

A complicating factor here is that changes in the shape of the tube cause reflections, or changes, in the sound waves: Where the section of the tube grows in diameter, there will be sound waves reflected back towards the start of the tube. These waves will be the opposite of the original waves that they reflected from, so they will also be negative pressure waves.

Aha! The next important discovery was made--by gradually increasing the diameter of the tube, a gradual, more useful negative wave could be generated to help scavenge, or pull spent gasses out of, the cylinder.

Adding Divergent Tubes, which used to be called "Megaphones," to Two-Stroke Pipes Helped Make Useful Power

Adding Divergent Tubes, which used to be called "Megaphones," to Two-Stroke Pipes Helped Make Useful Power

Putting a divergent cone on the end of a straight pipe lengthens the returning wave, broadening the power band and creating a rudimentary expansion chamber.

So, to sum up, when the negative wave reaches the exhaust port at the correct time, it will pull some of the exhaust gases out the cylinder, helping the engine to scavenge its spent exhaust gas. And putting a divergent cone at the end of the straight (parallel) "head" pipe broadens the returning wave. The returning negative wave isn't as strong, but it is longer, so it is more likely to find the exhaust port open and be able to pull out the exhaust gases. As with plain, straight pipes, the total length of the pipe with a divergent cone welded on determines the timing of the return pulses and therefore the engine speed at which they are effective. The divergent cone's critical dimensions are where it starts (the distance from the exhaust port to the start of the divergent cone is called the "head" pipe), while the length of the megaphone and the rate at which it diverges from the straight pipe determine the intensity and length of the returning wave--A short pipe which diverges at a sharp angle from the head pipe gives a stronger, more straight-pipe-like pulse. Conversely, a long, gradual divergent cone creates a smaller pulse of longer duration.

In addition, the negative wave is also strong enough to help pull fresh mixture up through the transfer ports.

And while adding a divergent cone to the head pipe produced great tuning advantages, it had its limitations, too: The broader negative wave from a megaphone can still arrive too early and pull fresh mixture out of the cylinder. That's exactly the problem that Walter Kaaden had with the factory MZs. He realized that putting another cone, reversed to be convergent, on the end of the first divergent pipe would reflect positive waves back up the pipe. These positive waves would follow the negative waves back to the exhaust port, and if properly timed would stuff the fresh mixture that was pulled into the pipe back into the exhaust port right as the piston closed the port.

In addition to head pipe length, divergent and convergent cone lengths, an expansion chamber has three more crucial dimensions. The length of the straight 'belly' between the divergent and the convergent cones, the length of the tailpiece 'stinger', or muffler, and the diameter of the belly section. The stinger acts as a pressure bleed, allowing pressure to escape from the pipe. Back pressure in the pipe, caused by a smaller-diameter or longer stinger section, helps the wave action of the pipe, and can increase the engine's performance. This, presumably, happens since the greater pressure creates a more dense, uniform medium for the waves to act on--waves travel better through dense, consistent mediums. For instance, you can hear a train from a long way away by putting you ear to the steel railroad track, which is much denser and more uniform than air. But it also causes the engine to run hotter, usually a very bad characteristic in two-strokes. 

Kaaden immediately realized a large power gain, and the expansion chamber was born.

The length of the belly section determines the relative timing between the negative and positive waves. The timing of the waves is determined by the length of the straight pipe. If the belly section is too short, positive waves have a shorter distance to travel, and return to the exhaust port sooner. This is good if the engine is running at a higher speed, bad if you want to ride on the street. The diameter of the belly section is crucial for one simple reason: ground clearance. It's hard to keep big, fat pipes off the ground, though V-Fours have solved that for now since two of the pipes exit directly out the back.

A complete two-stroke pipe has properly tuned header, convergent, belly, divergent and stinger sections--a difficult process.

As the forces in a two-stroke pipe design have become more well-understood, designers have been able to create engines that take more advantage of them and in fact require an expansion chamber to run at all. For instance, a modern pipe has a gently divergent head pipe to keep gas velocity high near the port, a second cone of "medium" divergence, and a third divergent cone with a strong taper. A belly section connects to multi-angled convergent cones, which should exit in a straight line into the stinger for good power. As you can see, modern two-stroke expansion chambers create a complex scenario and are quite difficult to tune.

Mandatory Maintenance Instructions

1. How to Adjust Clutch if signs of slipping or squealing are encountered:
A) Disengage the clutch by pulling handle bar clutch cable lever inward and push the lock button in.
B) The bike should now roll easily. Release the clutch lever and bike should slide the rear wheel.
C) If the rear wheel does not slide when the lever is released this means the clutch needs adjusting.
D) Remove the clutch cover and then remove the locking screw that holds the Clutch Adjusting Nut.
E) Pull the clutch lever arm on left side of engine inward. Back off the Clutch Adjust Nut ½ turn CCW.
F) Release clutch lever arm and check for 1/16" slight clutch arm free-play.
G) Readjust *Clutch Adjust Nut as required to get the required 1/6" clutch arm free play.
H) Now Repeat the B) roll test. Rear wheel should now slide when the handlebar lever is released.
I) Be sure to re-install the small locking screw in outer edge of *Clutch Adjust Nut.
G) Good idea to place a small gob of grease at gear mesh area. Use grease sparingly! Then replace cover.
H) Squirt light grade oil down clutch cable sheathing to reduce friction and make for easy lever pull.
2. Carburetor
Carbs now sent to the USA per instructions from the Dept. of EPA the idle and air fuel mixture screws must be epoxy sealed or made non adjustable at the factory to avoid end-user tampering. NOTE: Carbs sent to all other countries DO NOT have these air/fuel adjustment restrictions. Depending on clean vs. dusty riding conditions, clean air filter every 5 to 20 hours of operation by removing the filter cover to access the screen and element. Wash element with a de-greasing agent such as Simple Green™ or Purple Stuff™. Be sure element is completely dry before re-assembly. NOTE: If engine runs poorly clean tank shut off value filter.
3. 3 pt. Spark Plug
Remove spark plug and inspect for excess carbon build up. Clean, re-gap to .0.036" of an inch if necessary. Check plug after every 20 hours of operation. New spark plugs are available from your dealer. Be careful using aftermarket spark plugs as heat range and threads differ greatly. the stock plugs are around an 8 heat range. 7 hotter, 9 cooler. A 6 seems to be a good performance upgrade. An extra plug is included: When replacing the spark plug in an Angle Fire head it's best to use a 3 point electrode spark plug P/N Z4JC to ensure total combustion. ( Ask your selling dealer for it by part number. ) Electrical components such as magnetos and spark plugs are not warranteed.

4. Exhaust system
After 50 hours of operation check exhaust pipe for excessive oil and carbon build-up. If muffler is clogged your dealer has replecements.Make sure attaching nuts are tight and no exhaust leaks are occurring. Be sure to use supplied support strap to secure exhaust muffler to a solid anchor point on bike frame or engine.
A) To remove inside catalytic exhaust insert loosen the retaining screw on end cap and remove.
B) Pull cap and baffle out of pipe. Note: Some catalytic inserts are welded in and cannot be removed. If you need a replacement muffler contact your dealer. 2010 models have an air shield welded on the outside of muffler again per EPA rulings. This insures hot run so catalysis can clean the exhaust.
C) Clean with degreaser, rinse and dry. Re-assemble: File muffler attach flange to have smooth flat surface.
D) Always use a new exhasut gasket and good idea to use double nuts on muffler attach studs;
*NOTE: Excessive periods of low speed operation, idling or leaving fuel petcock in the “on” position during shut down periods may cause the Spark plug to foul with excessive fuel/oil mix, muffler to become clogged with unburned fuel as well. inspect the plug if the engine begins to run rough, has a hard time starting, or runs rough at max cruise speed.
5. Standard Bike 1/2x1/8” Chain is included in kit. HD 415 is available as an option.
Every time the bike is ridden check the tension of the drive chain by:
A) Rolling to bicycle forward to remove slack from the bottom of the chain.
B) Find the center and push downward on the top of chain while measuring the deflection.
C) Tighten chain by loosening rear axle nuts, and pulling wheel backwards, simultaneously tightening nuts withou letting the chains slack.  if deflection is more than ½ inch call for assistance.
6. Head Bolts
Tighten all fasteners after each five hours of operation. Most important to check Cylinder head bolts : Tighten in a X pattern to 15 ft/lb using a torque wrench. A two piece cylinder and head design engine requires head bolts be kept tight. Important: Check head bolts before each and every long ride, vibration can cause them to loosen and blow a head gasket. Caution: Do not over torque or head bolts may break off. ( Twisted or broken head bolts due to over tightening is not covered by warranty. )
7. Right side gears:
Remove cover plate and keep small amount of heavy grease on gear train. Do not over grease as leaks will occur and also may adversely affect clutch operation. Regular greasing if required will help reduce gear wear and keep gear train quiet.
8. Left side drive:
Routinely pack grease on the clutch 47mm long push rod located at the 10T sprocket and also in cover hole around the lever cam. This will make easy clutch lever operation.
Items, tools and extra service parts in tool kit; Typical Engine ID plates.
General Information
Obey all traffic regulations. Always wear a helmet while riding. Remember that you are riding a motorized bicycle and other traffic may not be able to see you. Never operate your motorized bicycle on a pedestrian through way or sidewalk while the engine is operating. Never operate your motorized bicycle in an unsafe manner. Check local and state laws before riding on streets & wear a helmet.
IMPORTANT: PLEASE READ THIS: Gas and OilMixture for Fuel ratio
The engine is a 2 cycle design, therefore, a gasoline/oil mixture is necessary to keep it from seizing. During the break-in period (1st gallon of fuel), the ratio is 16:1. 16parts gasoline to 1 part 2 cycle oil. After the break-in period, the ratio is increased to 24:1. 24 parts gasoline to 1 part oil. The engine crankshaft bearings are lubricated from the oil in the gas mix. A rich break in mixture ensures bearings will not cease. !WARNING! Remember safety first: Wipe up any spilled fuel. NEVER fuel a hot engine or light a cigarette while fueling. Especially don't try to light a cigarette from the hot engine. This could result in sudden fire, personal injury, loss of eyebrows.  Always move your motorized bike at least 10 feet from any fueling area before attempting to start it. do not try and cook an egg on the engine or exhaust pipe. this will make the engine sticky, and may damage the painted finish. Also, Never leave the tank fuel cap off after fueling as rain water will contaminate the fuel and cause engine failure.
Step #1. After filling tank with the correct oil/gas mix open the tank fuel valve. Fuel line is in the open position when the small lever is pointed down. Move choke lever to the on (up) position. This is the small lever on the right side of carburetor.  All the way Up the choke is on. All the way Down the choke is off. Move progressively downward to off position during engine warm up period.
Engine Starting procedure for Lever Clutch Models:

1. Pull the handlebar clutch lever inward, to disengage the engine from the rear wheel.
2. Pedal; (down hill if possible for first start)
3. A mid frame or rear wheel bike stand is helpful to start the engine in place.
4. Let out the clutch lever all the way out and continuing to pedal. The result is a direct engine hook up via the friction clutch with the rear wheel via chain and sprocket. The engine will now start spinning as you Pedal until motor starts. as it starts "popping", or firing, reach down and push the choke lever back down a bit with your LEFT hand, as you gently rev the throttle, coaxing it to start popping stronger.  you will find the "sweet spot" where it wants to fire. Accelerate slowly at first, and turn off choke after a few seconds of it running.
5. Twist throttle to increase speed, release twist throttle to decrease speed. To stop, disengage clutch (pull lever IN) and apply brakes. To accelerate, pedal and release clutch smoothly while increasingly opening throttle.
6. omit choke redundancy statement
7. As soon as possible  push choke lever all the way down. If engine races too fast, or too slow, pull clutch lever and lock in the notched catch, stop and adjust engine rpm.
8. If the rpm needs adjusting, turn the idle adjust screw (found on the left side of carburetor) in (clockwise)  to increase rpm, or out (CCW) slowly to decrease rpm. obtain the proper idle speed of about 1500 rpm. The engine is best not to idle. plugs will foul at extended low rpm.
To correctly break the engine in, do not exceed 15 mph or exceed 30 minutes of continual running for first tank of gas. Note: Engine will develop more power after break in.
9. To stop the engine, push Kill switch and turn off gas valve at tank. Turning off the gas will prevent fuel from being siphoned from tank. Warning Note: Never leave the tank gas valve in “open” position” when engine is not running or the bike is in storage.
10. After or before each ride check all mounting fasteners, including hd. Bolts, axle and brakes.
11. Warning Note: Engine lock up or piston seizure due to improper gas / oil mixture will not be covered by factory warranty. This the responsibility of the owner / operator to make sure the gas and oil is mixed correctly.

how to tell if you have a Grube or another make of engine. Grube's have their own piston/crank setup. the rod is longer, and piston shorter. This is hard to tell if you have nothing to compare to, so we have added these for you to check out!How to tell if your engine in a Grube or a different make.
Website Builder