China 80cc Longevity Kings: List your milage and key to success!

Discussion in '2-Stroke Engines' started by Bronzebird, Aug 14, 2008.

  1. Bronzebird

    Bronzebird Member

    HT 80cc Longevity Kings: List your milage and key to success!

    Read that someone has over 6,000 miles and still going strong... Since I'm new to motoredbikes and have the 80cc Chineese 2 stroke as my introduction to the fuel sippers. I understand re-torquing heads and obvious outside parts for good maintenace before each ride. But what about the not so obvious, like good oil that worked for you. Flat or hill terrain. The 6K post stated wide open throttle for maximum oil to the crank and bearings?

    Also i have a left over part that looks like a bearing press. But no directions on how or where to use it? Do I need to check motor part with it before break in of my new motor?

    16:1 stated in black and white direction booklet for fuel ratio. Is more better or will this delay piston seat to cylinder wall.

    18:1 in the full color description manual.
    Last edited: Aug 14, 2008

  2. the do hicky thinga ma-jig Is a fly wheel puller in a sort of way.
    You don't need to worry about that tool unless something goes wrong.

    AS to the Ratio.
    16 to 1 is fine for breaking in for the meek. IF you tend to worry then run the 16 to 1 for a few tanks

    Careful and safe is always best when it comes to moving parts and heat.


  3. pedalpower

    pedalpower Member

    just went to Castor927 ~25:1. It hums at 25 mph at about 1/2 throttle. at this point I'm trying to get my clutching down for smooth take offs. I am wondering if an ounce of some other oil/stabilizer will help with our E10 fuel.

    my key: warm up-always.
  4. Bronzebird

    Bronzebird Member

    Castor 927 @ 25:1 is in first place for the moment

    Bob you have been an excellent resource of info since my feeble "PM" questions answered with the understanding of the learning curve for a noob.

    Warm up go it!
    1- How many miles have you gotten or have on the HT?
    2- Exhaust mods for 1/2 throttle at 25 mph?
    3-And taking off with the clutch? Is pedal start easier on the clutch plates for longevity? Just asking...maybe they out last the motor? (noob Q)

    I hope to see some competition and bragging rights surface from the Kings.
    Because I want to learn from the pros !!
    Thanks from the Oregon rider with hills.

    PS: Second break in ride was clocked with my wife's Prius at 15mph and 20 mph. Speedo quit working. Does the electronic ignition or Plug wire cause interference with the Cat Eye front tire speedo?
  5. Bronzebird

    Bronzebird Member

    So have you modified stock porting or intake and exhaust manifolds

    I see performance of air and gas flow enhancement to stock delivery. Making a seemless transistion from intake manifold to cylinder intake port and the sam for the exhaust side. Just wonder "how much of a difference" is noticable in MPG and increased HP.
  6. Skyliner70cc

    Skyliner70cc Active Member

    Castor 929 at 25:1 is too much oil. Try 40:1 and you'll like it. At 25:1, you are increasing risk of a stuck ring and fouling a plug. The 20% castor in this oil goes a LONG way in protecting your engine.
  7. 2,800 on my HT. I splurged for a jug of castor early on. Now because I'm poor I'm running 1/2 castor,1/2 valvoline from the auto parts store. Since I converted over to MOOP2 it does not collect any dust anymore. I've been adding Valvoline 2 stroke oil to my castor container so by now it's probably 25% castor 75% Valvoline.
    (But Cronus is catching up in miles.)
    My HT is showing NO signs of weakening whatsoever. In fact,sometimes I think it's actually improved overall.
    My secret is I ride it like an old man on a bicycle with a little more speed. But not a whole lot more. I don't lug it but I don't wind it out either.
    I run 18mph MAX speed when cruising with the occasional burst but since MOOP2 has but the rear coaster only because I want this bike to look original I don't ride fast at all. My cruising speed I would guess right now is 14 to 17 according to the speed radar sign. 44t sprocket.
  8. motoschwinn

    motoschwinn Guest

    3200 miles on mine

    3200mi and going strong on my early Kings motor. Still all the original parts. I used Quaker State 2 cycle from the word go. For those that put down this motor, and there are lot's of them on this site. Well the motor outlasted the bike! So it's now on Motoschwinn II.

    Attached Files:

  9. I will admit ..
    I have one of the first Bikes I ever Built ..It has been thru **** and Back.HeHeHe

    It has over 4000 Miles On the " Rat BIKE "
    And the steering head bearings and races are Wasted from all the pot holes i have hit at 30 mph Not to mention the salt damage from dropping it in the water off the boat:grin:
    A couple Times ( I don't want to get into that one).

    Anyway check out the video We made today for all the ..uhmm

    Heavy guys that call me asking if the kits will carry them.:shock:

    check it out



    Last edited: Aug 15, 2008
  10. Bronzebird

    Bronzebird Member

    I guess these are unmodified or cleaned up motors.

    Since I did not do any Dremal grinding on manifolds, I was wondering how many other motors did or did not? "Stock" is untouched out of the box like mine. Stock muffler too!
  11. Bronzebird

    Bronzebird Member

    Muffler is not stock any more...

    Ughh...8 holes one quarter inch drilled in the baffles. A bit over kill and noisey but so far I like the throttle response.
  12. spad4me

    spad4me Member

    To address your speedo problems.
    I use a super cheap like $6.00 speedo.
    Your plug should be clean, and about 17 to 23 thousands gap.
    You must use a resistor type sparkplug wire.
    You must mount the speedo sender on the rear wheel as far from the cdi as possible .
    And route the wire from the sender using the frame to help shield the wire from the cdi.
    I also use the gas tank with a big foam mount for the speedo display.
  13. alex

    alex Guest

    I have almost 4,000 miles on my old king's 80 engine, It has always started within 10-15 feet of popping the clutch. And I broke it in with 20:1 and now I have run it with 32:1 using castrol 2t oil. I was very disciplined when breaking it in, I never once went over 15 mph or rode it for more than 15 minutes for the first 50 miles.

    Oh, and I have no hills near me (except when I sneak onto golf courses)
    And I haven't done anything major to the engine except put a better spark plug wire on it and an expansion chamber.
  14. Bronzebird

    Bronzebird Member

    I got the speedo working again had to move the front fork sensor about 2mm from spoke magnet. Now it is working perfect again. (wierd interferance is gone)

    Expansion chamber question how much did that improve speed performance and MPG? Or did you loose MPG with more throttle gunning? 4K miles is very impressive, keep her going and maybe you will be in the 6K club! Thanks for the break-in tip.
  15. alex

    alex Guest

    With the expansion chamber, I noticed a big increase in torque and take-off but no real increase in top speed. And my mpg didn't go down any.
  16. You know? Me Too!!
    Yes. My engine outlasted MOOP 1.
  17. Bronzebird

    Bronzebird Member

    Reversed the exhaust mod back to almost stock.

    I plugged the quarter inch holes except for 2 at the top baffle. All bottoms were plugged and sealed the factory spot welds. The noise would be a great reason to get a cop to pull me over. Working on rules of the road and safety lighting and gear. I have seen two patrol cars and none seem to care I was cruising in the bike lane with my bike helmet and blue trail of exhaust from break-in fuel mixture.
  18. chrisnbush

    chrisnbush Member

    I got 1500 miles only :-( on my CH80 "no name" I purchased on eBay. Learned a LOT about engine mounts, air leaks (carburator side), tires, chains, grease (on everything), clothes to wear, clothes to not wear, bicycle tire bearings, tool kit (10 mm open end, crescent wrench, screwdriver with bit assortment, spare engine studs and bolts, spare plug, etc.), check all bolts prior to every ride of any duration, etc.

    Lots of hills here, my upper bearings were trashed, happend on the flat at low speed JUST AFTER posing for pictures at a local gas station JUST AFTER mixing a tank of gas + oil in the tank.

    I only ever learn by doing things wrong, sometimes a couple of times ! But thats OK.

    I just got my new DAX CH80 up, that I bought at Fall prices (!) on eBay. 134 with shipping - fantastic. Roller bearings upper, but bushing lower, may be better on the bushing anyway. For this build ->

    1. Fingernail polish a.k.a loctite on engine mounting bolts on engine side.
    2. Double nuts on mounting bolts, 2nd one as a security feature.
    3. Rubber mounts on the engine clamps (what works best is bike intertube split lengthwise about 6" long on both frame tubes).
    4. Rubber mounts on gas tank, cdi mount.
    5. Plumbers tape on fuel petcock threads into tank
    6. Plumbers tape on top of carb where cable mounts (this can come loose and cause air leak).
    7. I don't use any kill switch, had problems with the first one shorting out, couldn't start the engine and spent a lot of time figuring out why. I just dump the clutch at idle - don't know if this is good.
    8. I put washers + lockwashers on some bolts that don't have them, e.g. where chain guard attaches to engine.
    9. Grease front and rear bike wheels complete using a grease NEEDLE and grease gun.
    10. Dab of grease on drive gears under clutch plate cover. Lithium grease doesn't appear to spread real well here.
    11. Religious break in period.

    After break in, I will put cardboard (or coat with silicone) on underside of clutch plate cover, as I learned on the forum, as this cuts down on gear noise. A lot of noise indicates need for grease, I had to grease the old one frequently.

    My 2 cents