Whats the best 4 stroke kit, available on the market today

Discussion in '4-Stroke Engines' started by Spanner, May 16, 2012.

  1. Spanner

    Spanner New Member

    Hi all, Having fitted a 4 stroke kit recently, what is the best for stroke kit out there at the moment. the one that I fitted seemed on paper to be a good thing but once assembled and ridden it really didnt live up to my expectations. so rather than throw good money at another lemon, what is the best, most reliable, well tested, kit. and why?

  2. LR Jerry

    LR Jerry Well-Known Member

    I use the Staton Inc crank drive kit on my auto shift bike. I live in Tennessee so there's lots of long grades and steep hills to contend with. I use the Robin Subaru EHO 35 engine. David Staton is really good person to deal with. The setup I used allowed me to keep the auto shift feature on my bike.

    From what I read there are several good kits and dealers out there. You should contact several of them then evaluate which dealer and kit will work best for you.
  3. jbcruisin

    jbcruisin Member

    I like my EZ drives.

    <a href="http://s472.photobucket.com/albums/rr82/jbcruisin/EZ%20bike/?action=view&amp;current=100_1093.jpg" target="_blank"><img src="http://i472.photobucket.com/albums/rr82/jbcruisin/EZ%20bike/th_100_1093.jpg" border="0" alt="Photobucket" ></a>

    <a href="http://s472.photobucket.com/albums/rr82/jbcruisin/EZ%20bike/?action=view&amp;current=QMatic008.jpg" target="_blank"><img src="http://i472.photobucket.com/albums/rr82/jbcruisin/EZ%20bike/th_QMatic008.jpg" border="0" alt="Photobucket" ></a>
  4. loquin

    loquin Active Member

    Define 'Best' ...

    • price
    • performance
    • quality/reliability
    • ease of installation
    • appearance
    • maintainability(how easy is it to work on?)
    • spares availability
    • rider weight
    • terrain
    • climate
    • ...
    and, there are probably more things to consider. They ALL enter in to the mix, and every person's definition of which of these factors are important, and which are less so, is different.

    For the first seven factors, think about them, and give them an importance weighting, of 1 to 10, say. Then, when comparing the various kits, you could assign them each a estimate of how well they meet the factor you're considering - also, from 1 to 10. When you've done that, multiply the two numbers together for each factor, add the results all up, and compare the numbers... the bigger the final number, the 'Better' that kit is ... for YOU.

    In my case, (I want a system that is well made, very reliable 'out of the box', that I can spend my time riding, and not adjusting/fiddling with/repairing,) my personal importance weightings would be

    • price: 5
    • performance: 6
    • quality/reliability: 10
    • ease of installation: 5
    • appearance: 1
    • maintainability: 8
    • spares availability: 9

    I've attached a spreadsheet with my evaluation of some of the kits. Adjust it with your importance ratings, and your 'intangibles' (weight/terrain/climate, etc.) In my case, climate is hot and dry, so friction drive gets good performance marks. In a wet climate, not so much...

    Attached Files:

    Last edited: May 17, 2012
  5. 4strokr

    4strokr New Member

    If you're looking for best price, there is someone selling a 4 stroke kit in southern CA. for $299 with free shipping, it sparked my ear, but they will not answer the phone or return messages, honor their warranty claims(broken gearbox). For what I thought I saved, I've spent in repairs. The HuaSheng engine is really good, the drive train is where it counts. Grubee has a good one and ThatsDax is a good place to look
  6. Spanner

    Spanner New Member

    Thanks for the imput, read the spreadsheet, what are you on about LoL, What I want to know is, what takes off like a 2 stroke with minimal pedalling, it has to fly over the steepest hills, Be bulletproof with no manufacturing faults or suspect materials or weakspots, or false claims of superior performance. Eg: is the skyhawk 4gt a worthy kit? its been around a while now, how are people finding it, or is there something better?
  7. Anigai

    Anigai New Member

  8. LR Jerry

    LR Jerry Well-Known Member

    The engine is only one part of the equation the drive system also plays a big part.

    Here are important questions to consider when building or buying for yourself or others:

    1) What is the predominant riding terrain?
    (Level ground, hills, asphalt or dirt etc...)

    2) What type of physique does the primary rider have?
    (Large, small, short, tall or health issues etc...)

    3) What will the rider's local laws allow and require them to have?
    (Lookup and personally read these laws.)

    4) What kind of bike is being motorized?
    (Mountain, road, whizzer or recumbent etc...)

    5) What is the bike to be used for?
    (Shows, long trips, around town, off road or racing etc...)

    6) How much of a budget is to be used for the build or buy?
    (All at the start or as you can afford projects etc...)

    Seek the answers to these questions in order to get the most out of the bike you're building or buying. We're here to help with any questions you may have. The purpose of the "Questions to Consider" is not to overwhelm or confuse you. Rather help you focus in on what will work best for you and help you develop a building and/or buying philosophy. This site has lots of people who can help you but the only way they can is by asking questions. Any one of the questions to consider somebody here can help you with.

    A fool never learns from their mistakes.

    A smart person learns from their mistakes.

    A wise person learns from the mistakes of others.

    Good luck with your build or buy.

    "I became rich by hiring people smarter than me". Andrew Carnegie
    Last edited: May 18, 2012
  9. The_Aleman

    The_Aleman Active Member

    I have nearly 5000 miles on my HS and 5:1 4G through a SBP kit, the motor itself has been bulletproof, aside from the carburetor gumming up kinda easy.

    I had a few problems with the 4G clutch and clutch drum, but nothing a replacement didn't fix. Grubee has improved them since I bought mine 2 years ago.

    IMO, the best all-around kit is an EZM Q-matic with Huasheng. My brother bought the very first retail production Q-matic, it's proven to be pretty reliable over the last 2.5 years. His being an early model, it had some pulley problems leading to early belt failure, but since that's been sorted out he hasn't had any problems with it. It's a foolproof system that takes a lot of abuse.

    Also, I wouldn't say the Honda is necessarily better than the Huasheng. For sure the Honda is a lil quieter, built tighter, but it won't necessarily outlast a Huasheng. My brother has a GXH50, had to rebuild it before he hit 2K miles. There's several people on this forum with over 10,000 miles on their Huashengs. Vote with your wallet, not your emotions.
  10. dimsdale

    dimsdale New Member


    I baught an EZM and could not be more inpresed! With a small amount of maintance and mods this kit will reach 45mph and up. Engine and trans combo is simply brillant! You will spend more time riding than fiddling with it.
    When I first got my bike going there were lots of cheap 2stroke bikes running around town, 8months later there are none around they have all gone the way of the dodo.
  11. loquin

    loquin Active Member


    Well,in Australia, you're legally VERY limited as to engine output. 200 watts (1/4 HP!) I believe.

    A motorcycle or commercial moped would fit all your 'specs,' (the "fly over the steepest hills" is the kicker!) but not much else.

    A 50cc Honda with a Staton gearbox, or a 35cc class honda/rs with a pocket-bike CVT, geared for a top end of 25 MPH/40 KPH would also probably work well. (takeoff at low speed, hill climbing ability, decent top end) The fact is, a single gear ratio setup won't work well for all your requirements, unless the engine is quite large.

    (FYI, setting up a weighted matrix with the various criteria that you find important/unimportant is a good way to determine the 'best' of almost anything for yourself... As I said, what's 'best' for you, may not be 'best' for me, or 'best' for someone else, as everybody's criteria for 'best' is a little different.)
    Last edited: May 20, 2012
  12. loquin

    loquin Active Member

    As far as Honda not being necessarily better than H/S... That is true. But, the odds are, it will be. Honda and Robin/Subaru BOTH have top-notch manufacturing facilities and both have a great quality control system in place. That being said, it is still possible to get a 'lemon,' but if you do, these two companies are known to stand behind their products.

    With the H/S engines, we have no idea what kind of quality control system they use, and they don't necessarily have any sort of reputation to maintain.

    I bought a 78cc HF 4 stroke engine, and it had a small casting defect on the engine cover (near the shaft seal) that let the oil seep out. I caught this before the engine was installed, but it took 8 weeks for parts to get shipped from China to fix it. If I had installed that engine right away, and ran it, it could have easily have ended up trashed pretty quickly...
  13. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi Everyone,

    Just returned from the event in Dawson Springs, KY, and just wanted to let everyone know we tried to "trash" the Q-Matic drive via Drag Races and Roller Road tests. Final results concerning probems are as follows:

    The bicycle chain came off during one of the tests. The bicycle chain, not the motor drive chain, and the bike still won the dirt drag race. It was the chain on Jay Cruise's bike, and only effected applying the brakes at the end of the run. Who needed to stop anyway, LOL.

    There were several EZ bikes at the event, however we spent most of our time testing the Q-Matic drive on the larger motors [99 CC HF]. We just wanted to see if we could break one of the drives on the more powerful motors. We tried everything we could think of to abuse the drive system and all the EZ bikes are still working just like new.

    Guess our new slogan could be "Race Proven".

    Have fun,
  14. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    Hi Quenton, it's only 4 days to the SoCal Motor Bicycle Racing event
    on Sat June 2nd at Grange Motor Circuit.
    It will be the 4th race on go kart tracks in CA since June 18th 2011.

    There is a racing class for 50 cc 4 strokes and smaller so I am inviting
    you and EZ Motorbike to field a bike on the track.

    There is also a mid range class that a 99 cc HF with a Q Matic could
    compete in.

    This is racing on asphalt with corners on a challenging 7/8 mile 14 turn
    track with a 950' straight. 12 lap finals are 10 miles.
    None of us race or ride dirt drags.
    Winning on the track is a test of a bike that has meaning in the real world.

    An EZ Motorbike Q Matic has never won any of the 4 races, in fact a
    bike using a Grubee 4 G gearbox is the reigning champion.

    If you want to make the claim that the EZ Motorbike is "Race Proven"
    put your bike on the track and win some races! :D

    Here is Grange Motor Circuit.

  15. flashstar

    flashstar Member

    I still think that the 4g drive kit with a HS motor is a great deal. I've had more engine problems than issues with the 4g drive kit (make sure to reset your valve clearances before your first ride!). The only drive failure I've had involved the drive chain popping off the rear sprocket. I don't have a chain tensioner and sudden engine torque delivered in a turn caused the chain to derail.

    Anyway, I've only put about 225 miles on this bike so I will revise my opinion when I put more mileage on it.
  16. dorourke

    dorourke Member

    I just bought a flying horse 49cc 5g kit from BB with the belt tran. I haven't heard anyone mention anything about this engine and hoping to get some imput from other users. I had some problems with the two strokes and finally spent the money to support my adiction of riding. It comes with the 44t sprocket and they claim to use Japanese bearings. I'll find out in a week for myself if it was worth the money. any suggestions would be welcome.
  17. Happy Valley

    Happy Valley Active Member

    Lou, I know both this is an old debate and you favor precise information. I prefer the Japanese engines myself, own both Honda and Robin Subaru and have always held it's a toss-up between those two in quality. It has sometimes been suggested that since Honda went offshore with some manufacturing, their QC might have suffered but that always seemed based on rumor or misinfo about being in Taiwan or something rather than their dedicated facility in Thailand.

    That said, what do you make of this?

    Delivery Lead Time: 15-40days
    Minimum Order: 800pcs
    Supply Ability: 10000pcs

  18. Old Bob

    Old Bob Member

    Thats a rumor, Honda will thank you kindly for not giving it any credibility.
    Honda's commitment to quality in the Thailand plant is the same as any other manufacturing facility Honda maintains.
    They do not farm out any engine manufacturing.
    R/S quality has always been marginal, some neophytes justify R/S not deburring the piston skirts on the EHO-25 and -35 as being there to better scrape oil off the cylinder wall.... its just bad practice and a cost cutting short cut.The quality of the die castings for the engine aren't even the same color top and bottom of what are supposed to be match machined upper and lower assemblies. The color difference is a change in alloy composition and its subsequent difference in hardness will affect the bearing bore size and shape.
    R/S is lagging behind Honda in both quality and design but is better the cheap knock offs.
    MotorBicycleRacing likes this.
  19. Happy Valley

    Happy Valley Active Member

    Do you work for Honda or speak for them? It's not a rumor it's a trade website as anyone can plainly see. Further, it's a website showing a pic of a Honda GX35 and details of how minimum lots of 800 pieces are available with inventories up to 10,000 pieces originating from mainland China.

    Now whether it is legitimate, misleading or outright incorrect information I cannot say. That's why I asked the question but note I also posed the question to Loquin simply because I trust his precision and evaluation in many things mechanical. You're entitled to your opinion as well of course but unless you have credible proof contradicting the info in the trade website I'll consider whatever you contribute to just another guy's opinion. What I have seen is a history of argumentative posts on how great Honda is. Perhaps you're invested there or perhaps you sell them . I do not and don't think Lou does either. I own Honda engines and am very satisfied with them as I do Robin Subaru engines and am equally satisfied with them.....as an end user and consumer.....for the particular purpose of motorizing a bicycle. BTW, do you have a motorized bicycle?
    Last edited by a moderator: Jun 6, 2012
  20. loquin

    loquin Active Member

    I don't know if the chinese source is valid, or a knock off, but the fact that they are advertising them with the Honda logo certainly implies that they are genuine.

    Honda would have to verify they are now sourcing at least some of their engines in China before I would venture to say anything about the engines being built there. IF they are sourcing their engines there now, I am SURE that they would have their QC program in place and working, before they sell any engines from that source.

    However, I AM curious as to why Honda would allow their manufacturer to sell directly, instead of only through Honda. Typically, an engine maker would ONLY sell bulk quantities through their own sales department; they would NEVER allow a supplier to sell THEIR branded engines on the open market.
    Last edited: Jun 4, 2012