GY6 Swapping The Honda Ruckus: What To Expect From Your Swap

Travis @ Buggy Depot

Travis @ Buggy Depot

Founder of Buggy Depot and NanoEFI. Certified buggy nut, riding enthusiast and GY6 mad scientist. Contributor to the sport since 2002. Member #7 on BuggyNews Forums, and hosts the Yerfer.net and GX150 Yahoo Group archives.
Travis @ Buggy Depot

If you’re considering a Ruckus 150cc swap, this is what you need to know from the start.


Update July 25, 2015: This a reboot of our popular article from 2013, which was downloaded 100,251 times.  Thank you to everyone who continues to find this information helpful!


This article isn’t meant to cover installation practices, but is more of a heads-up for hang ups and issues you should expect during and after a GY6 swap into your Ruckus.  This article also won’t be talking specifically about the BDX swap kit, but covers general issues you may experience with any GY6 swap whether doing it yourself or purchasing a packaged kit.

The popular GY6 150cc engine

The popular GY6 150cc engine

What to expect during installation

Installation should take anywhere from 1 to 5 hours, but may take more depending on your experience and level of mechanical skill. I’m a doctor, not a mechanic! We frequently get asked questions from guys interested in swapping who don’t really have much mechanical experience. These guys are typically in search of a 150cc swap kit which will involve the least amount of head scratching and will run smoothly right after installation. While most packaged kits are straight forward to install (to varying degrees), the truth is, there will always be some tuning and tweaking after installation to get everything working correctly. Swapping for the novice in many situations is going to involve minor install gremlins that have to be worked out after the swap is complete.The main thing is sticking with it and asking questions along the way. We’re happy to answer installation and calibration questions for our customers, and we also believe there is no such thing as a dumb question, so by all means ask away. The expectation for the novice going into any swap should be that it’s going to be a learning experience and that extra time should be anticipated. Going into a swap with the right expectations and a healthy level of patience can be the difference between having a properly installed engine setup that purrs at idle, or a hack job that can barely be started. Take your time and ask questions!


What to expect for reliability

There are some reliability issues across the board with swaps that should be known.

Expect some bogging and hesitation issues (with vacuum fuel pumps)

The majority of GY6 swaps (including our kit) use the common Mikuni fuel pump, which is driven by vacuum pulses that the engine generates while running. They work well to get fuel to the carburetor, too well actually. The vacuum operated fuel pumps seem to frequently be too powerful for original and aftermarket GY6 carburetors, forcing extra fuel past the internal valve. This extra fuel then gets forced into the intake tract, which is then sucked into the engine. This impacts fuel economy and causes the bike to run rough and erratic at low speeds, often killing the engine when coming to a stop. We’ve setup a return line on our dyno to demonstrate how much extra fuel is being pumped by a Mikuni pump paired to a GY6. What you’re seeing is the extra fuel constantly exiting the float overflow tube of the carburetor and flowing back through our return line on its way to the tank. If you’re able to fabricate a return line to your fuel tank, this works well and solves the over-fueling issues. But this isn’t a reasonable solution for most swappers. We’ve experimented with restrictions in the line and other methods, with varying levels of success. The most elegant and effective method we’ve found of getting around this issue is to keep it simple and stick with the original Ruckus electronic fuel pump. The stock electronic pump seems to be best suited for this job, avoiding over-fueling issues with the help of the stock ECU or an external pump controller. Currently, only harnesses which use the original Ruckus ECU are able to use the stock fuel pump – but the ECU is big and bulky so most harness makers opt to remove it from the system. Our harness doesn’t use the stock ECU (removed for a clean install and to avoid clutter), but we are developing a special stand-alone controller which will drive the stock pump and also allow you to adjust pump output.

Expect charging issues with 8-pole Stators

GY6 engines usually come with 6-pole or 8-pole stators which typically don’t output enough power at idle to charge the battery while running the headlights. This is a minor inconvenience most of the time, but can lead to a dead battery and huge headaches under the wrong conditions. The simple answer to this is to upgrade to an 11-pole stator, but this isn’t totally necessary.A side note, if you have severe battery charging issues (while riding), this isn’t normal and there is a fault in the system. Contact the maker of your harness and try to get an answer as to what’s going on.


Expect less longevity than the original Honda 50

But also expect less expensive replacement parts! In this way the cost of maintenance equals out, especially if you consider all the extra power of the GY6 150cc. Factors that affect reliability: Air-cooled Cylinder Design This is an area where the original Ruckus engine really outclasses the GY6. The GY6 is air cooled (versus the liquid cooled stock engine), which means that the GY6 is generally less forgiving to less-than-excellent maintenance habits and won’t last as long as the 50cc Ruckus engine if not well taken care of. On the other side of this coin, GY6 parts are generally far less expensive than the 50cc parts and easy to get from dozens of vendors online. Our best advice is to practice preventative maintenance – frequent and timely oil changes and routine air filter checks. Electrical System Wire quality, internal wire connection methods, and fuse protection play major roles in how long your electrical system will last before popping a connection loose or frying something. Unfortunately, there aren’t really any established resources out there that compare the quality of wiring practices between harness brands. Warranty Coverage varies between vendors who offer warranty against defects. Be sure to check with the seller for warranty details. The BDX warranty:

  • Engine & Power train: 2 years/10,000 miles
  • Electrical System: 5 years/20,000 miles
  • Engine Mount: Lifetime

What to expect on Maintenance

Oil Change Intervals (1000 miles per change)

The Ruckus service manual specifies an initial oil change after the first 600 miles, and then changing the oil routinely every 2500miles. With the GY6, we recommend an initial oil change after the first 100 miles, with subsequent changes every 1000 miles.Recommended engine oil type is 10w40 of a reputable brand. Synthetic is not necessary, but should not be used at all until after the break-in period. Final gear oil should be replaced every 2500 miles.

More Vibrations

The GY6 vibrates. A lot. This will cause nuts and bolts to come loose if not properly torqued. Things like aftermarket mufflers may also repetitively loosen over time if not properly supported. A dab of red Loc-tite 272 works very well for larger fasteners, while blue Loc-tite is better for smaller fasteners. One of the most important fasteners of the swap is the rear axle nut, which secures your rear wheel to the engine. We offer a vibration resistant locking nut.


Expect way more speed and power

We’ve talked mostly about the downsides of GY6 swapping, so closing this article with the positive aspects of swapping seems appropriate.

  • 55 – 60mph top speed The numbers speak for themselves. With double the horsepower rating, you can match and maintain traffic speeds, even up decently sized hills.
  • Big time acceleration boost Again, this goes without need for much explanation. Expect a lot more torque for stop and go traffic. Roughly speaking, the GY6 will accelerate a Ruckus from 0 to 30mph about the same as the original engine reaches 0-15mph.

Bottom line: Swap it yourself!

We advise against having a local mechanic shop attempt to install your swap. Small engine shops aren’t familiar with the Ruckus and can end up having just as many questions as you would, but they’ll be charging you per the hour to learn the same information that you can get at no charge. If you feel totally over your head for the install, it is best to seek out one of the many shops that deal specifically with Ruckus installs. Many can be found on the forums. However, we highly recommend using the swap as an opportunity to learn and get yourself familiar with the workings of your swapped Ruckus.


Need help with your Swapped Ruckus?

We get a lot of calls and direct messages from Ruckus owners that have non-BDX swap kits (sold by other vendors) that are looking here for technical advice.  We’re happy to lend a hand, but be aware of the following:

Visitors asking for advice please note: In order to quickly help troubleshoot your problem, confirmation is needed from you at each step that you understand any directions offered and that you have followed them completely. 

Please provide relevant details of your results, so that one of our Techs or Engineers can figure out the next troubleshooting steps for you. Help us to help you. Thank you.

23 thoughts on “GY6 Swapping The Honda Ruckus: What To Expect From Your Swap

  1. Steven

    Thank god I found your website I have a gy6 150cc doing the swap myself of coarse, I was wondering if I should do all the body work and whirring first or ,engine first.

    • alistair young

      Actually the info here has put me off im no mechanic and at that stage in life where i would love just to buy one already with the gremlins sorted out…… god! why didnt honda make a more powerful version of this?. i know that it was aimed as a sort of urban shopping bike and built for economy not speed thrills but in all the years it was manufactured you would have thought that honda thru feedback would have introduced a more speedy version.

  2. joey

    Hi, ok I brought a 09 ruckus about 2 weeks ago off of Craigslist. It’s a 150cc gy6. Now the problem I’m having is the bike has no power like a 150cc should, I thought about changing out the CVT kit, it’s has 11 pole stator. The most the bike will do is probably 25mph. Thanks I really need help on where to begin.

    • Travis @ Buggy Depot Buggy Depot

      Joey, can you give more details about what other symptoms are you are seeing that might be contributing to the lack of power? Hesitation, backfiring, etc. If the bike is doing anything else odd it would be helpful to know.

  3. joey

    The bike sometimes take several time to turn over, it hesitate and shuts off,if I ride it and most time come to a stop it shuts off.its also backfires when I try to start it up and sometimes when driving it.not quite sure if I eats up gas or not. Thanks joey

  4. joey

    I also checked the oil and it’s filled to the top. I’m not sure if that’s a big difference or is effecting the power.

    • Travis @ Buggy Depot Buggy Depot

      Overfilled oil won’t cause a power loss, but it will cause oil to spew from the valve cover.

      Part of the problem sounds like over-fueling (described in the article above), combined with lack of fuel during startup. First step should be to get clear fuel lines if you don’t already have them. You’ll want to watch to see if the fuel drains back to the tank when the engine is off. If so, that probably explains the hard starting. Gas doesn’t reach the carburetor for some time while cranking. This leads to a prematurely dead battery often from needing to use the starter so much.

      For the power issue and backfiring while riding. Here is a test to see if your pump is over fueling. Get the engine running the best it can, and to the point where it is showing symptoms then turn off the engine. If you have a vacuum-operated fuel pump, disconnect and plug up the vacuum line coming from the intake manifold. Make sure to plug up that vacuum line, or it will throw the test off. Start the engine again and ride it around. The engine should run much better for about a minute (until the float bowl runs dry). Reply with your results.

  5. joey

    Ok, now the bike have been starting right up, but still lack of power and i think it’s burning too much fuel. How can I over come this? Thanks

    • Travis @ Buggy Depot Buggy Depot

      Joey, did you perform the test I outlined for you? It is unclear in your response.

      Visitors asking for advice please note: In order to quickly help troubleshoot your problem, I need confirmation from you at each step that you understand my directions and have followed them completely. I need details of your results in order to figure out the next steps for you. Help me to help you. Thank you.

  6. joey

    I don’t understand what u mean, but I realized that my automatic choke is not hooked up to anything, so i can’t not make adjustments to rich or lean it out. This could possibly be my problem as far as the fuel going in and out the carb. I took the carb out and there is fuel in it. Is the automatic choke important that it has to be hooked up? If so how do I fix this matter?

    • Travis @ Buggy Depot Buggy Depot

      Joey, the automatic choke isn’t adjustable (it’s automatic without any settings). It’s not likely the problem judging by on the info you’ve given so far.

  7. ricky

    would a 2013 vip motor fit a 20o8
    ruckus

    • Travis @ Buggy Depot Buggy Depot

      With a proper swap mount and harness to support it, yes the 2013 VIP 150cc engine will fit.

  8. ricky

    im looking for a good motor swap i heard you can swap 98 2 stroke zuma motor would that be a good choice

    • Travis @ Buggy Depot Buggy Depot

      The 150cc GY6 is the standard go-to engine for Ruckus engine swaps. It’s well supported with a solid following, and reliability of GY6 swaps is routinely being improved. As a personal preference, I’d stay away from anything 2-stroke for reliability among other reasons.

  9. Peter

    What’s all needed to do a full GY6 150cc swap? Links of parts will help. Thanks!

  10. stelios

    Hello to everybody and specially to the person that wrote this article…. I recently get on a pics from a fatty rockus … I totally fall in love … And I wonder … after percuating a ruckus (zoomer in greece ) Can I fit Sh300 engine ? Do you know if someone ever swap an engine like this .. ?

  11. Dan

    I bought a new motor for my lance 150. The old stator was 11 or 12 pole and the new one is 8 pole I believe. Rectifier has 3 yellow, one black and one green. New engine has green, white, yellow, red and blue wires. I am so lost, any help would be very much appreciated.

  12. Silver

    I am a little surprised that the GY6 150cc engine if straight swapped from a working scooter to a Ruckus would have massive over fuelling faults such that surely the standard scooter would have trouble being sold or massive reliability & warranty problems which would have driven dealerships nuts or a problem found before the engine was ever purchased for use in a Ruckus. I am also surprised that if a excess of fuel pressure is a problem a simple adjustable pressure regulator could not be fitted in the system as a suitable fix.

    Buggy Depot you are very brave to attempt to solve a problem with no close contact for sight, sound and smell, that Joey has given you (let alone the hands on testing you would obviously normally go through); he having bought what I assume is a failed project by someone else, Joey himself having apparently no idea about anything mechanical from the information given, and his problems possibly being any one or combination of excessive fuel, fuel starvation, vacuum leaks, ignition timing problem, and the excess oil he described (I also checked the oil and it’s filled to the top.). From the pictures I have seen of those engines if full to the top of the dipstick tube may see the lower half of the whole crankcase and bore swimming in oil which given crankcase ventilation back into the induction system may pose a slight difficulty including oiling up of the spark plug you have your work cut out for you. You also have no indication as yet by the information if the bike actually has compression (or as much as it should have).

    I am not knocking you, nor picking on Joey, just making the observation that at present the field is still wide open to possibilities with a lot of narrowing down to do with your eyes, ears and senses being that of a person who did not really understand the first thing you asked him to try. On a more positive note however backfiring that he mentioned and the several tries to get it to turn over lend itself to a thought of ignition timing being over advanced. Backfiring itself is often associated more with too lean or advanced ignition timing rather than an excess of fuel. (Unless the backfiring he is talking about is actually in the exhaust not the intake which is not really backfiring but some people call it that). May I be so bold as to suggest he checks his spark plug, maybe puts in a new one then attempts to run it for a few seconds or even for a minute or 2 then rechecks it and tells you what he sees, also the condition of the old plug. (Plug gap, old plug oily, fouled/sooty; new plug is it wet or dry). These things I have said for Joey’s benefit, I have no doubt Buggy Depot knows all this and a whole lot more.

    Good luck. I am curious as to how this will all go.

  13. Alexa

    What engine do i buy? i see just the normal gy6 150cc engines on ebay for around $200-$300, but then i see engine swap kits going for $2000!! I don’t have that kind of money and i just want to do a 150cc gy6 swap that is efficient and is not expensive

  14. Chris

    Hello I’m in the process of a Honda ruckus+ a gy6 Chinese 150cc VIP=chucks
    Which fuel pump would I use and would I use the ecu or bypass it? Need an answer asap thank you.
    PS I don’t have time to check this
    7025832618

  15. Fisher Warren

    I am about to swap my 2009 Honda Ruckus to make it a GY6, but I do not want to stretch it out. I want it to have the same factory look but just with a bigger 150cc motor. Any help would be appreciated

  16. Tom Lane

    Your advice is very helpful. We have been having no spark problems for the past few days. Now I know exactly how the GY6 works. Thanks.

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