Newbie Needs Some Advice

Discussion in '2-Stroke Engines' started by packrat79, Jul 10, 2008.

  1. packrat79

    packrat79 New Member

    I just got my first motored bike kit, a basic 49cc engine from an Ebay vendor by the name of powerkingshop. It took me two days and many hours of frustration to get the thing working, thanks partly to poor instructions and also to the overall cheap design of this thing. I have it running anyway, but there are some big issues that detract from its performance, some of which will have to be corrected.
    1. Vibration. While my gel seat absorbs enough vibration to keep my posterior quite comfy, the vibration at the pedals is enough to badly assault the nerves in my feet. I suspect I haven't mounted the motor solid enough, and also I probably need some kind of suspension for the motor itself (one guy here posted some pics of his idea, but no clear instructions on how to do it).
    2. The other major problem is that the thing doesn't seem to have enough power to get up steep hills. Many of the remote trails I enjoy biking on - and even our own driveway - have some very steep inclines that I'd rather not have to walk up. I'm not sure if there's anything I can do about this or not, other than upgrade to a more powerful engine.
    Another problem is the clutch; it requires a very hard squeeze to disengage, which I must do if I need to slow down (especially on turns) without stalling the motor. Again I don't know if there's any way around this.
    I'd appreciate any advice you could offer me regarding these problems. Obviously it will take a lot of time and experimenting to get optimal performance from this thing - but it's still easier than saving the money to buy a real motorcycle.

  2. stude13

    stude13 Active Member

    hi 79; ok you got it and found some drawbacks. brand new and having problem with steep hill. they take serious break in time and much tinkering. readreadread then ask. i would pull up a chair in the shade, pop a cool one and stare at what you built. ill have one with you. mitch
  3. BoltsMissing

    BoltsMissing Active Member

    You may need to post some pictures of your build

    Some instructions here:

    Your power range will not happen till the engine is runin after about 500 to 1000 kilometers

    Fuel ratio for runniun is 16:1
    Then 20:1, I have heard some go a slean as 25 or 30:1
    Use high quality 2-stroke oil Stroke Fuel-Oil Ratios.htm

    Your clutch is stiff cos you need to oil the cable, then again a picture would help to see if it's fittted correctly

    Augi used to say, READ READ READ !
    There is heaps of info. here.

    All the Best

  4. packrat79

    packrat79 New Member

    I've posted a couple of pictures of the motor mounts. As you can see, it did not fit well and required a lot of improvising. You'll also notice that oil has been spitting out around the muffler gasket - perhaps it isn't tight enough?
    The clutch is even more of a problem though. Even if I move the clutch arm directly by hand, it still requires a LOT of pressure to move. This morning while trying to grip the clutch control (which required both hands to do) the cable actually broke off at the handle, so now the entire cable will have to be replaced. I can't see why the clutch requires such force to disengage - nothing I did seemed to make much of a difference.
    There seems to be a problem with the throttle too; while riding the bike around the yard this morning, the throttle stuck full on after starting (the handle still moved but didn't seem to do anything), and in my panic I forgot to hit the kill switch and ended up having to jump off at almost 20km/h.
    Needless to say I'm very disappointed in this rig. Everything about it seems to be poorly-built - not surprising since it was made in China. I've taken the motor off while I try and figure out this mess, but I'm considering leaving it off for good. Do-it-yourself or not, nothing should be this troublesome to install and operate.

    Attached Files:

  5. BSA

    BSA Guest

    For gods sake put some spacers on the studs on that front motor mount, it will make it much stronger and safer.

    Last edited by a moderator: Jul 13, 2008
  6. eljefino

    eljefino Member

    You did read here first before buying the kit? Nothing you've found is unexpected.

    For the clutch, take the cover off that side, pull out the cylinder-and-ball, grease everything, and put them back in the order in which they fell out.

    The difference between cursing and having a good time with these kits is a sense of humor. Lack that (go into "I got ripped off" mode) and the little idiosyncracies will get to you.
  7. As well as the front, you need to make a SOLID mount for the rear. I dont know what is stuck in there between the mount and the frame, but I guarantee that will break.......I would mount the rear solid and in place then worry about how to mount the front. The torque from the engine wants to pull the engine backwards and to the left, so rear is very important....
  8. Skyliner70cc

    Skyliner70cc Active Member

    No go on the engine mount. Please for the sake of your safety do it correctly (use search engine). You are asking for a chain to fly off and cause problems such as sudden stoppage or whipping off and hitting your leg or cracking your engine case...ask me how I know.
  9. lildeezul

    lildeezul Member

    I also bought and ride and powerkingshop off of ebay.

    personally i think its pretty darn good. The instructions were clear to me.. and went on with ease.

    It comes with a plate... for the big round frames.. look at my albums, i think i have a picture of my mounting setup.

    As for the clutch issue,,. yes they are hard to pull, becuase ONE the arm is very short, you need to move it over a couple of splines, or do what i did, and make a pulley system for mine.
    Look in my albums for my clutch setup.
    I hadnt have any problems with my Powerkingshop engine, i also purchased the 49cc. (the 80cc are the same price). one steep hills, what i do is just peddle, with the motor. it doesnt require much energy...
    but my motor pulls strong, i also have a problem with the vibration once going down hit around 30 and 35mph...

    but also, on they ebay page, they advertise that this motor achieves 250 mpg, which is wrong, its about 125-150 mpg.

    The only problem i had with my is my chain tensioner ( crappy_), and that it gets to top speed to quick. but all i got to do is change the rear sprocket.

    i wonder if i can put a 36 tooth sprocket on my 49cc, and still be able to peddle hills. with the motor
  10. Skyliner70cc

    Skyliner70cc Active Member

    For hill climbing a 55 tooth rear sprocket is your best bet. I use a 50 tooth on my 70cc engines and they are perfect. I don't need to go faster than 25mph and love climbing hills that are steep.
  11. packrat79

    packrat79 New Member

    Your pictures are too small to make anything out, do you have larger versions?
    The pulley idea seems like a good one, I also thought of adding an extension to the clutch arm so that less force is required to move it.
    You're also right about the tensioning wheel; it simply wouldn't stay in place, and I ended up having to drill through the frame and lock it in place with a bolt. Also I don't think the cheap plastic wheel will last long so I'm going to look for a sprocket to replace it with.
    The motor mounts will be the hardest thing to figure out. Someone on here posted pictures (perhaps the ones I tried to view now) of a suspension mounted motor; if someone could provide some detailed instructions on how to built that, I would appreciate it.
    I didn't expect this to be a simple install, but I didn't think it would be quite to challenging either. I think if these things are ever going to catch on, they'll have to become more manageable to those lacking in mechanical skills - and patience.
  12. lildeezul

    lildeezul Member

    oh yeah... Troy made the suspension motor mount i also thought about doing that as well..

    Oh yeah,, with the tensioner, i also drilled a hole through my frame, but it will still move.
    it was ****. i discarded it, and took some links out of my chain so it will be tight enough without a tensioner..

    go to

    that is my album, i have pictures and vidoes of my fourweeler, and bike
  13. GasKicker

    GasKicker Member

    I can see only tragic results coming from your motor mounts. Fortunately, there are many threads on here concerning motor mounts, engine vibration, chain tensioners, clutches, etc. Read alot and you will be fine. But, please do something about those motor mounts right away.

    The problem with simpifying the installation is that there are differences in the bike frames we choose to put these on. There is no "one size fits all" solution.

    Just my opinion.

    FYI: I have gottten 9 kits from Powerking. The instructions are almost useless. Every bike frame build is a little different. Sometimes the kits are different. Overall, I'm satisfied that I got what I paid for.
    Last edited: Jul 17, 2008
  14. Ghost0

    Ghost0 Guest

    To improve the clutch arm movements remove the extra spring. The clutch cable assembly comes with 2 springs. The large one is to be used as a heat shield to keep the cable housing from melting against the cylinder. The other spring that goes between the cable adjuster on the engine to the clutch arm should be discarded. It is not necessary and only makes pulling the clutch in harder. Also make sure to lube the cable.

    Check this our for good mounting technique.
    Last edited by a moderator: Jul 17, 2008