Need Advice?

Discussion in 'Photos & Bicycle Builds' started by twitch0601, Jan 9, 2015.

  1. twitch0601

    twitch0601 New Member

    Hi, I am New to this site and to motorized bikes in general. I have looked into building one before but life happened. So now i am looking to build my first one soon. I just need some help and advise.

    First off, I am looking into buying a skyhawk frame, but there are 2 different ones. I would like to use the 4 stroke 7g motor kit. I am wondering if anyone knows for sure if that kit will fit into the GT2-A frame? i know that the info on it says it will fit a 4 stroke but every build i come across online people use the GT2A-S frame. I really want to get the GT2-A frame because its about 65 dollars cheaper. Would i have to cut off the motor mount? or what?

    Second, I am asking because i have a KHS downhill bike that all the parts will fit on the Frame and i really want to use that frame because i hate the look of the tank that comes with the kit.

    If anyone knows anything about the frame or motor, please help me out. im not looking to go crazy with diferent parts and upgrades and shift kits. i just want to start off simple. Im not looking for speeds or distance, just a project to get me started.

    Thank you to anyone.

  2. HeroesNeverQuit

    HeroesNeverQuit New Member

    Not a builder but if you mean 4 stroke 7g motor kit as in the ghost racer 7g T-Belt engine kit then your bike will not be able to go on the roads as that engine is not E.P.A. compliant. Just thought I would let you know.
  3. KCvale

    KCvale Motorized Bicycle Vendor

    Yes the 49cc HS142 4-stroke will fit in the GT2-S (the S is for Straight bar), just barley.
    It's the same engine that has been EPA for years, the EPA just haven't got around to certifying them again because of last years government shutdown so they throw those stickers on them to get them imported.


    That is a jackshafted 3-speed internal shifter but the engine sits the same as direct drive.

    The GT2-A has an S shaped downtube ( I know, confusing) and would make mounting a 4-stroke much easier.
    You may have to cut some of the 2-stroke pedestal off, maybe not, and maybe you could even tie the base to it, I have not tried one of those frames yet but I know the geometry.

    Also note that none of the GT2 frames has are real Grubee's, they are knock-offs, that doesn't make them bad and I haven't seen one, just a heads up.

    You do know what is involved in building a bicycle from scratch from just a bare frame correct?
    It's not even painted.

    If you want the most bang for your buck and the best ride I recommend going the way I did, a 4-stroke jackshaft kit and 3-speed internal.
    The $200 SBP shift has your entire bottom bracket and much better engine base included, and I got that yellow rimed 3-speed wheel set for like $130 delivered.
    That leaves nothing but the front fork, brakes, and tires to buy.

    Hope that helps ;-}
  4. twitch0601

    twitch0601 New Member

    Thank you for the advise guys

    To, HeroesNeverQuit, thanks for that heads up, i just moved to California and i didn't even think of that.

    To, KCvale, your bike looks good man, great work, very bright. I actually have lots of experience with building bikes, cars, painting, pretty much everything. but i dont have any building a bike with a motor. So i figured i would ask the people who do it all the time. Hell, i have even built a tall bike once and thought about putting a motor on that.

    I think im going to go ahead and get the gt2-a frame cause i like the s-shaped downtube.

    Im just a little confused on the motor. I wanted to pick up the ghost racer 7g but i guess its not epa certified? is that a big deal? can anyone even tell. what should i do? put a sticker on it?

    Is there a better 4stroke kit thats already certified without killing my pocket?

    thanks again for the help, i am researching and learning alot, i just like to ask anyways in case i cant find any answers.
  5. KCvale

    KCvale Motorized Bicycle Vendor

    The HS 142 IS EPA certified... for 2014 and every year before.
    It's just a sticker above the 2014 EPA sticker because the EPA has been backlogged.
    Just pull it off or cover it with another sticker like I do if it's EPA or not.


    The EPA is catching up, Don Grube finally got 2015 EPA certification for the Skyhawk 2-stroke engines making then the ONLY epa certified Chinese engine allowed into the US and he has a shipping container coming ;-}