Curious about the engine, :question:

Discussion in 'Motorized Bicycle General Discussion' started by mapbike, Jan 8, 2015.

  1. mapbike

    mapbike Active Member

    Joined:
    Mar 14, 2010
    Messages:
    5,380
    Likes Received:
    1
    Does anyone have any experience with these engines I see popping up more and more on ebay and a couple other places, I know they been around for a while but I haven't really heard anything about them.

    These look to have the wider 40mm intake bolt spread and the little shorty china-lume intake, I'm thinking most of what I'm seeing means these are fairly new kits since they seem to have the new CDI that has the better rubber plug boot instead of that junky one that all the older kits have always had.

    [​IMG]

    [​IMG]

    [​IMG]
     
  2. maniac57

    maniac57 Old, Fat, and still faster than you

    Joined:
    Oct 8, 2011
    Messages:
    4,486
    Likes Received:
    3
    I've not seen that intake, but the motor has been around awhile under a few names, gt5 etc.
    The 40mm intake brings better ports and port timing along with the wider front mount saddle for larger frame tubes. I have one like this sitting on my bench except it had no intake when I got it, so not sure it's the exact same motor.
    [​IMG]
    This shows the wide intake needed for these jugs.
    [​IMG]
    Been seeing the longer bent clutch arm awhile too, usually only on the better quality motors regardless of intake size.
     
    #2 maniac57, Jan 8, 2015
    Last edited: Jan 8, 2015
  3. mapbike

    mapbike Active Member

    Joined:
    Mar 14, 2010
    Messages:
    5,380
    Likes Received:
    1
    Maniac57. I'm thinking these are PK-80 40mm stroke engines since all the sites I've seen that sell these as their only engines or kits sell the Type A pistons and not the GT5 Type B pistons.

    About the longer bent clutch are, a few year ago I bought an engine only from BGF that is painted with a shiny gray paint and it has the longer bent arm, it came with a good looking crankshaft that is drilled and the transfer ports in the jug and case are the biggest I have ever seen and they are even shaped differently just a tad, it has silky smooth bearings in it also and like you said the one I have does have the larger front mounting area that fits perfectly on the Huffy and other larger cruiser frames, mine doesn't have 40mm wide intake stud spacing since as far as I know they hadn't made those yet back then and I'm thinking the Grube Super Rat was the first to have the 40mm intake stud spacing.

    These ones that I'm seeing now don't say anything about having the larger front mounting saddle.

    More than anything I'm curious about whether they have a good crank and rod in them, based on the shape of the transfer port areas hat extend out on the sides of the case I know they aren't the same engine as what I got from BGF back then but the rest of it looks the same basically right down to it being painted silver and all the hardware for the covers being flat blade screw driver type fasteners and Hex head bolts directly under where the jug meats the case.

    An example of the engine I have in the pic below, look at the transfer port area on the side of the case and notice the shape the ports are larger and with mine the jug was made that that its ports matched the case, even the base gasket was shaped differently just a little and matched the larger ports.

    [​IMG]

    [​IMG]

    [​IMG]

    And below is a completely different type engine that has the 40mm intake stud spacing which may be a GT5 TYpe, I'm not sure.

    [​IMG]
    [​IMG]

    Oh well maybe the only way for me to find out for sure what they are is to just buy one and have a look see at it..LOL..!

    I was just thinking that surely someone on here had bougt one of the from and ebay seller and might know a bit more about them as far as quality. they look to me to be a newer version of the old original PK-80/Power King Engine that was about the best that there was a few years back, but the the case isn't exactly the same because of how the transfer port is shaped on the case of this engine, Pirate Cycles used to sell some of what looked to be the original PK-80 but I think they were a lesser quality Re-pro of them.

    Hmmmm, once I get past tax season and all I may have to just get one of these coming in the mail so I can find out what it is, might be a good candidate for a build to sell, I want to build a couple bikes to sell this spring and I'd like to find the best quality for the least so I don't have to charge to much for the bikes, these kits are actually cheaper than rose326 and I like the longer clutch arm and shorty intake that give more room and these come with the newer CDI that doesn't require a boot upgrade.

    Thanks maniac57, looks like we both have an idea what these may be like in some ways but I still have a question or two that may not get answered until I get one in front of me and get the jug pulled off and the side covers so I can see some of the guts of the whole thing.

    Map sits and scratches head in Central Texas this morning where it is 14F degrees... dang its cold for us down here today damp and just plain bone chilling....!
     
  4. curtisfox

    curtisfox Well-Known Member

    Joined:
    Dec 29, 2008
    Messages:
    4,083
    Likes Received:
    47
    So were did you get that from?....Intresting.............Curt
     
  5. mapbike

    mapbike Active Member

    Joined:
    Mar 14, 2010
    Messages:
    5,380
    Likes Received:
    1
    Hello Curtis, I found several sellers on ebay that have these kits, a couple are in California and others mainland China.

    Here is a link to one of them that I have dealt with in the past, very nice people and they shipped quick and had good follow up through messaging to make sure I got what I ordered and that I was happy with my purchase.

    http://www.ebay.com/itm/NEW-Hand-St...332?pt=LH_DefaultDomain_0&hash=item3a9e44f094

    I may try one of these soon for a build to sell locally just to see how they are put together, I'm curious about which crank and rod these have in them and if these are Hybrid type engine with Type A piston and jug but with the 38mm cranks which kinda jacks up the port timing, a little jug shaving and piston ramp on exhaust side helps to fix that issue, but I cant find any specs on these to know if they're 40mm stroke engines or the 38mm stroke hybrid type, I know they use PK-80 type piston and jug since the sellers that sell these have the replacement top end kit and you can see that the piston is a Type A piston.

    One thing I will do if I order one is I will chuck the intake up in the lathe and bore the ID out a bit, in the pix you can tell its very thick and has a small ID.

    Map
     
  6. KCvale

    KCvale Active Member

    Joined:
    Feb 28, 2010
    Messages:
    3,890
    Likes Received:
    19
    The REAL Grubee GT5a 2-stroke with 2015 EPA should be hitting the US shore to Don Grube's Midwest warehouse by early March FYI.
     
  7. mapbike

    mapbike Active Member

    Joined:
    Mar 14, 2010
    Messages:
    5,380
    Likes Received:
    1
    Thanks KC, I'll be interested to know what has been done different with those engines compared to the others we have available now.

    Map
     
  8. curtisfox

    curtisfox Well-Known Member

    Joined:
    Dec 29, 2008
    Messages:
    4,083
    Likes Received:
    47
    Thanks map i have never owned one but this sounds intresting and may order one. I sorta 4 stroke man..................Curt
     
  9. mapbike

    mapbike Active Member

    Joined:
    Mar 14, 2010
    Messages:
    5,380
    Likes Received:
    1
    They may be good engine and they may be a big crap shoot... but the price is right to check one out I think just to curb my curiosity, someone is gona have to get one and see what its all about to know for sure, we know they're out there but so far no one here has rang in and said oh yeah I have that engine and its great or oh no I have or had one and it was junk... I just like to know what all my options are.

    I know for a fact that the engines that Neil Senior/ motorbicycleracing sells and the engines that Dax sells are top notch and honestly there mau not be any of the rest of them that really hold a candle to them, I know Fred Chelminski speaks highly of the MBR and DAX engines and I have four of them myself, one of them has developed to much end play in the crank after I ran it klike I was trying to blow it up, so I need to go into it and figure out what has happend but as far as being smother than all the other I've had they are and they produce good power with some basic mods.

    Well if you do order one Curtis and beat me to the punch be sure and keep me posted on what the quality lokes like.

    map
     
  10. KCvale

    KCvale Active Member

    Joined:
    Feb 28, 2010
    Messages:
    3,890
    Likes Received:
    19
    Basically, they are legal to import ;-}
    Skyhawks are made in the YangDong China factory and they make a damn good engine.
    If I'm not mistaken that is the base DAX starts with too as they don't have a factory and darn sure don't have EPA to import them yet if they did.
     
  11. curtisfox

    curtisfox Well-Known Member

    Joined:
    Dec 29, 2008
    Messages:
    4,083
    Likes Received:
    47
    Won't be anytime soon as got to many other projects going on.............Curt
     
  12. GoreWound

    GoreWound New Member

    Joined:
    Dec 1, 2014
    Messages:
    480
    Likes Received:
    0
    I didn't know this, good thing I bought one! The only local seller I could find had Skyhawks.
    I haven't test driven it yet (soon hopefully, damn winter) but when I do, I will be reporting back with what I find.
    I don't have a good camera but if anyone wants a specific picture taken of the motor let me know here or in the build thread over in Lowriders & Choppers, I would be happy to oblige.
     
  13. mapbike

    mapbike Active Member

    Joined:
    Mar 14, 2010
    Messages:
    5,380
    Likes Received:
    1
    Curtis I just looked over on JNMotors.com and see that they are selling the type engines that I posted the pix of.

    The intakes are odd ball, the standard we're used to is the ones with a 32mm center to center bolt pattern and then we have some now with the 40mm spread, these engines with the shorty intake are a 35mm spread, a tad wider than standard but not as wide as the wider ones, no aftermarket intakes for these girls, and there kit says the ones they have come with a standard 410 bike chain like the older grubes used to do and some may still be that way, I'm not sure.

    They also come with the NT Speed carb which is a good extra in my opinion since fuel line size isn't as big a deal as with the regular NT carbs.

    I'm gonna go backk and look closer at the pics I posted after I post this to see if the other come with 410 chain and Speed carb, I wouldn't care for the small weak 410 chain myself, but the speed carb is nice and I can make my own intakes if I need to so that odd spread wouldn't be a big deal for me.

    http://www.jnmotorsbikes.com/product_p/jnm1289.htm

    Map
     
  14. maniac57

    maniac57 Old, Fat, and still faster than you

    Joined:
    Oct 8, 2011
    Messages:
    4,486
    Likes Received:
    3
    Okay now you have me curious to see if it's the high pin piston 40mm stroker.
    I have one of Neil's "GenV" 40mm stroke engines to compare it to if it turns out to be a high-pin engine.
    I'll de-jug it later tonight and let you know what I find.
    I really have no idea where this engine came from and it's the first assembled 40mm intake/wide mount engine I've seen so I have nothing to base any guesses on.
    But without having them side-by-side, it doesn't look like my GenV...might be wrong
     
  15. mapbike

    mapbike Active Member

    Joined:
    Mar 14, 2010
    Messages:
    5,380
    Likes Received:
    1
    LOL....


    Yeah I was kinda shocked when I read that these engines in question actually have a 35mm intake stud width.
     
  16. maniac57

    maniac57 Old, Fat, and still faster than you

    Joined:
    Oct 8, 2011
    Messages:
    4,486
    Likes Received:
    3
    All the other wide intake engines I have seen here were normal 38mm stroke engines.
    The only 40mm stroke I have seen in Memphis is my GenV. None of my customers has ever brought me one. And the only guy who had ANYTHING out of the ordinary only had the one wide intake engine and a few oddball 49cc's. Everything else about the engine was typical 38mm chinadoll. Just a better jug.
     
  17. mapbike

    mapbike Active Member

    Joined:
    Mar 14, 2010
    Messages:
    5,380
    Likes Received:
    1
    Well Maniac, because of the odd ball 35mm intake bolt width I went another route today and ordered an engine that specifically shows to have a 40mm stroke, I have no idea whether or not the lower is of good quality or not, I'll know for sure when I get the jug off and see the crank and rod, I'm gonna build a FOR SALE bike and this kit had a good amount of parts that I like and the price was good so I went ahead and stuck my neck out on the deal, may have been a mistake but then again it may be a good one, time will tell.

    $119.85 to my door

    [​IMG]
     
  18. Davezilla

    Davezilla New Member

    Joined:
    Mar 15, 2014
    Messages:
    2,708
    Likes Received:
    2
    Hopefully that engine will work for you, I know a lot of ebay sellers tend to over exagerate what these engines can do and all but most the time when they list specs like stroke length they're honest on that part...
    I've seen sellers claim these things put out 5hp or can make a bike go 40mph right out of the box or say they got a 19mm carb along with a picture of a speed carb next to a digital caliper and they're measuring the clamp instead of the actual carb throat, some of them have claimed the 40mm bolt spacing and then they show a pic of them measuring with the caliper on the bolts instead of at the center of the bolts etc...

    Of course, most of us already know what to beleive and what to ignore in their listings, but we definitely want the 40mm stroke and the good bearings on the crank. The jugs are always a gamble anytime we buy from a different seller because some have really nice transfers and others not so nice, and you definitely don't want oddball intake bolt spacing which would make upgrading nearly impossible.

    Hopefully this kit will work for what you intend, since it's a seller and not a keeper, you still want a good quality base engine that has room for upgrades by the end user. It doesn't have to be 40mph fast, but it should be reliable and able to push a bike up to around 30 (give or take a few mph), but I'm sure it'll have both reliability and decent power after you're done with the basic upgrades you mentioned.
     
  19. mapbike

    mapbike Active Member

    Joined:
    Mar 14, 2010
    Messages:
    5,380
    Likes Received:
    1
    Thanks Dave, yeah One thing I always look for is the bloated up claims of power and speed, I figure if they'll lie to ya about that then most likely they'll lie to you about all the rest, this seller didn't really make any claims the best I remember, just a list of what the kit would include and the engine specs which I asume are written down on something they comes with the engines.

    I'm hoping it has the good no markings rod in it like the dax engines, that will identify it as having a caged lower bearing and possible the better main bearings, if that is the case this is a very good deal on these kits in my opinion.

    Time will tell though and of course I'll share what I find good or bad.

    Map
     
  20. YesImLDS

    YesImLDS Member

    Joined:
    Jun 29, 2013
    Messages:
    954
    Likes Received:
    2
    Hey I bought one of those engines for my friend. It has a different intake pattern and is a GT5 I believe. His runs VERY well and could keep up with mine with very little mods done. The intake is a shorty intake and is far superior to the other stock intake that comes with these. In fact, I got another one of the intakes and drilled the holes out to fit onto my engine and it ran quite a bit quicker compared to my stock ported intake.

    Here it is after I ported it out and put it on my carb.
    http://i.imgur.com/rEeZgdo.jpg
    As you can see I had to modify the mounting points to get it to fit.

    Anyways it's basically the same engine, but with a different intake. Everything else was the exact same, but his seemed to run quite well.
     

Share This Page