Honda and HuaSheng possable Carb MOD

Discussion in '4-Stroke Engines' started by bideronit13, Oct 2, 2011.

  1. bideronit13

    bideronit13 Member

    I posted this at another site a few months ago and was going to try it and still am interested. I noticed after I posted it at the other site all the carbs disapeared on ebay and when one shows up the price is higher.
    I really want to try it but am worried about the fit as my carb area is in question so Im going to ask the seller to measure for me. I took another look at my space again and theres no way it will fit on my bike but you can try it.
    I really like this because the intake mount looks perfect for the GXH50 and HuaSheng clone.
    Another tight part of the MOD is the throttle assembly on the carb. The carb comes from a Honda Elite CH80 and theres an electrical choke that could be hooked up to the on off switch or maybe bypassed.

    http://cgi.ebay.com/ebaymotors/H41-...rcycles_Parts_Accessories&hash=item4842332f3c

    Check it out!
     
    Last edited: Oct 2, 2011

  2. bideronit13

    bideronit13 Member

    Another hint is that at smallenginewarehouse.com you can look up the jets for the GX100 and see that the Jets for th GXH50 are the same part number. This makes the fittings interchangeable. So you can fit a GX100 Jet in the GXH50.
    I say this becasuse there's other jets options for the GX100 that arent listed for the GXH50.
     
  3. darwin

    darwin Well-Known Member

    You can buy a diaphram carb to fit the hs or honda at bicycle engines, instead of gravity feed you get a sort of fuel injection and one would think better performance.
     
  4. HeadSmess

    HeadSmess Well-Known Member

    diaphgrams all the way. you can mount the tank anywhere :)

    and the twin needle butterfly throttles are sooooo easy to tune in :D

    old style slides a lil bit harder to get just right but are good, and these new fangled rotary barrel slide things are impossible to modify :shout: all the ones ive met at least...

    what actually fits on directly, iunno :(
     
  5. bideronit13

    bideronit13 Member

    Can we see some pictures please?

    The last time I checked for any after-market carb on the market like the diaphragm carb its been sold out for almost a year.
    I checked bicycle-engines and I don’t see it in the inventory any more.
    Maybe you can help out and supply a link if I’m mistaking.
    Thanks Again.
     
    Last edited: Oct 10, 2011
  6. darwin

    darwin Well-Known Member

  7. bideronit13

    bideronit13 Member

    I want to run the CH80 mod, so I'm looking for a machine shop to make a custom manifold so I can fit the carb in my build.
    I appreciate the help though.
    I couldnt help it so I went and purchased a Honda Elite CH80 Carb. Paid about $72 for shipping and everything.
     
    Last edited: Oct 11, 2011
  8. bideronit13

    bideronit13 Member

    I should get it in a few days. I cant wait to take it all apart. Its a used carb. I seen they also sell diaphragms for the carb but only time will tell and I'll take plenty of pictures. It seems the 1986 carb used a diaphragm. I purchased a 2006 carb. I'm really qualified at fine tunning carbs so its gonna be a breeze either way.
    I dont know if you all heard about the Honda GXH50 but the thing sounds like a motor with a blower on it already and has plenty of power. I just want to un-corke it a little more so I can pull a trailer.
    See Ya Later!
     
    Last edited: Oct 11, 2011
  9. darwin

    darwin Well-Known Member

    Yea honda 50 is a sweet motor and the best mab motor out there in my book. For friction drive w/adapter and clutch your looking at 500 bucks kinda pricey.
     
  10. bideronit13

    bideronit13 Member

    If you look at it at the standpoint of if using friction drive or anything other then the SBP shift kit you might as well get a clone.
    The Honda is key to the shift kit because low vibration and high performance. So friction drive or any other drive other then SBP 4 stroke kit is kinda like putting a Ferrari on a moped which would just limit the thing.
    The SBP shift kit allows 50MPH with low RPM = low wear on the motor. So a good mod would just make it that much better of a performance package.
    I have a couple more tricks up my sleeve concerning several more mods. I dont want to expose to much because if I do at this point people might say I was crazy or something like they do already from time to time.
    Its all part of having fun.
    Well from the stand point of reasoning as the several lines below the technology will fit rite in as the Pipe mod I already have is a smaller outlet so I need to enrich carbuetion.

    A smaller outlet opening end increases backpressure. This effectively decreases the powerband to create more low-end torque. It also decreases exhaust tone and enriches carburetion.

    A larger exhaust outlet end decreases back pressure. This widens the powerband at the top end. It also increases exhaust tone and leans out carburetion.
     
    Last edited: Oct 11, 2011
  11. bideronit13

    bideronit13 Member

    Last edited: Oct 11, 2011
  12. bideronit13

    bideronit13 Member

    Anyway I removed the Carb and attached a picture. There’s a plastic governor you can see in the picture as the governor is round and the port is square so it can be ported a little also.
    I have another guy checking his inventory for the specs on the manifold so it looks good.
    I took the restrictor/governor off. I thought it was epoxied but lucky Honda aint that cheap.
    I attached another photo.
    So probley better off with a custom spacer anyway.
    Another thing it wont hurt to port the square port to a round port because I can alway go back to the restrictor plate if needed plobley wont need it but it wont hurt like I said.
    Then just get a round mount on there and away the horses go.
    Im going to find out the quality of the crankshaft roller bearings then get ahold of king bearing they do me good with percision bearings. well see what going on.
     

    Attached Files:

    Last edited: Oct 12, 2011
  13. bideronit13

    bideronit13 Member

    I just figured it out and it kinda easy but what has to do with easy is SickBikeParts is going to own the 4 stroke 50CC class at the races.
    The last test I ran with my shifter I ran the throttle wide open and speed shifted that mean without letting the throttle go.
    It ripped all the way for over an hour before I brought it home in one piece. The next morning I made a mistake and broke the chain. With this mod I guarentee you SickBikeParts has the winning setup for you race bicycle racer.
    See Ya Later with the goods to back it up.
    Next time you try to get over on someone you should make sure you can fool them because I aint the one. Im going to give it all away rite here. Bye Bye easy

    Another design I’ve been working on for this project is a fiberglass packed tunable exhaust.

    I was going to have a machine shop create a prototype but now I have solved it for an easy solution is just to modify the regular 4-stroke exhaust pipes already sold with an insert for the fiberglass packing and using my dremel to redesign the power band.
    I just picked up some fiberglass packing for $11.20 off ebay. I'll show how to make the exhaust soon.
     
    Last edited: Oct 13, 2011
  14. bideronit13

    bideronit13 Member

    I received the carb today and attached a picture.
    To get the ch80 carburetor able to perform on the GX50, what is needed is to remove the starting enrichment thermal valve and seal off the internal vacuum chamber. If this is not done the choke will remain on and you would need a 12V battery to allow the choke to turn off.
    The reasoning behind this is the GX50 motor needs less gas to start then an 80cc motor. So the starting enrichment thermal valve is not needed. Killing two birds with one stone.
    There are also a lot of features on this carburetor like the limiter cap allows high altitude adjustment, air mixture screw (after 1985) that's factory set to 1 ½ turns out.
    The throttle assembly adjustment screw conducts the idle adjustment.
    So now I'm just waiting on parts.
    One bad ting about it is I'm going to have to buy a Honda Elite ch80 throttle assembly as the cable for the carburetor wont interchange with the basic motored bicycle stuff. But on the other hand the cable is real heavy duty so there will be no worry operation.
    I attached another picture with the carb and a penny in the slot were the starting thermal enrichment valve used to be. I'm just going to silicone over the penny.
     

    Attached Files:

    Last edited by a moderator: Dec 15, 2015
  15. bideronit13

    bideronit13 Member

    I guess since I'm putting a penny in the slot and the bike has poker cards on it. A good name will be "One Arm Bandit".
    When I was testing the bike last time I noticed at WOT or even half way the bikes rpm would flex.
    Today when I took apart the exhaust it doesn’t have a complete seal. I attached a picture but importantly is the steal ring that allowed an internal leak.
    So by this exhaust set up it should also take care of that. Parts are coming soon.
    If I cant get the intake correct with the parts I ordered that should be close I can just order another exhaust pipe then cut, port and polish it then use it for the intake
     

    Attached Files:

    Last edited: Oct 16, 2011
  16. bideronit13

    bideronit13 Member

    I'm getting real excited about the exhaust so I thought I put it out here.
    The end result after the internal and actually the exhaust is complete I plan to have three pieces of small fuel line sticking out the back of the pipe. Two pieces are going to be able to close with brass fitting. This gives the option of running one, two or three pipes allowing the tuning for low, mid range and top tuning.
    The rest of the design is almost complete down to a new idea of a red bull can if it fits. If not I'll find something that does and use O-Rings seals.
    For me I'm only going to have two fuel lines out the end so I can keep the staging correct. This is a rebuildible design so the insert can be taken out and re modified or rebuilt.
    I'm giving the credit to some members of my family.
    I attached a picture of the design for the muffler and if the red bull can dont fit just find something that does.
    I have some info after reading about the carb its that the carb has two screws for adjustment one being idle and the other air. It looks like a go.
     

    Attached Files:

    Last edited: Oct 18, 2011
  17. bideronit13

    bideronit13 Member

    Its important to create a seal in the front of the red bull can as best as you can with o-ring's or some JB weld previously dried. As long as its close it will be ok because the rear section of the can is sealed tight.
    I added a picture to make the seals simple as Im just going to use the top of a skaol can then JBweld it to reinforce and seal.
    Another good idea would be to reinforce the outside of the red bull can with thin wire mesh then JB weld it section at a time.
    When rapping the packing around the pipe there's a special tape the pro's use that would burn away later. It kind of needs the tape to insure you get enough of the packing in there. Wheter it burns away or not might not be an issue as long as the holes in the pipe are about 2 inches behind the seal.
    The rest is up to your imagination.
    I aint in a hurry so it might be while anyway.

    The last thing I was worried about was the limiter cap on the airscrew that limits airscrew adjustment and makes you buy new parts every time you overhaul the carb.
    So anyway I attached a picture shower were I'm going to machine off the blocker on the carb giving no more limits to what I'm doing.
    So anyway I have a green pen pointing to the part I'm cutting off.
    The only reason I was worried about it is because the difference in the combustion chamber size might need a new adjustment.

    There's no excuse for that being on there. I still cant imagine why its there.
     

    Attached Files:

    Last edited by a moderator: Dec 15, 2015
  18. bideronit13

    bideronit13 Member

    Check out this hog of a intake manifold. I need to order a few more parts but I only spend a certain amount a month on what I'm doing.
    I was using a small rotary tool and I'm going to need something better so I'll get a real dremel.

    The bore on the intake in the picture is to large (24mm) I just put it up there. It was off a crf50.
    There's an intake off of a Honda Trail 70 that's only 21mm bore. I'm going to get one of those.
    I thought the intake in the picture would be funny.
     

    Attached Files:

    Last edited: Oct 20, 2011
  19. bideronit13

    bideronit13 Member

    I was looking for an intake with 18mm intake hole and finally found one.
    Its going to need a little dremel work but it will be fine for cutting in half and using a hose to connect the two pieces.
    http://www.motorparts4less.com/products.php?id=38

    I don't know if anyone has ever seen one of these before but check it out, a universal intake adapter. The smallest intake hole I could find was 22.4MM and the one here is 22.5MM. Its not good for me The one above is a perfect intake hole size of 18MM.

    Ebay item number 330304544044
     
    Last edited: Oct 22, 2011
  20. Old Bob

    Old Bob Member

    Honda recommends a 7800 rpm limit on that engine, the big end on the rod is a plain bearing and not known to live at high rpm.With the intake opened up its going to rev beyond 8000 rpm.
     
Loading...