how far can you go on a 2stroke motorised bike

Discussion in '2-Stroke Engines' started by ant797, Mar 25, 2013.

  1. ant797

    ant797 New Member

    hi im planning on doing a 56km around 2hours max on a 2 stroke mountain bike its a japanese kit i think from ebay just wondering if they can make it that far non stop

  2. BAM

    BAM Member

    Yes give her hell when I go for a ride I go though a tank in a day 60 70 miles!
  3. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    What do you think will happen if you ride it for 35 miles non stop?

    I really doubt that your kit is Japanese, if it is the typical 2 stroke kit
    it is made in China.
    Do you have the kit?
  4. grinningremlin

    grinningremlin Active Member

    I've regularly rode 45 miles non-stop with the RS EH035, and Tanaka PF4000.I read one of Grouchos posts a while back, he wanted to test his ride and did a trip with the EHO35 without killing it for 6 hours ( I believe), drive-thru eating and filling while running.
    As long as you pay attention to the way it runs, and run it kindly I'd say go for it.
  5. Dankoozy

    Dankoozy Member

    The PF4000 is used on high end brushcutters that might be used the whole day. There is no wai engines like that should have any problems running for a long time, definitely not if it's a bit cold or average temp so the wind keeps it cool - the very cheap chickity China stuff might have bother but really they shouldn't and even if one of those packs up it's not the end of the world

    Vary the throttle a bit, some 2 strokes don't like being ran at the same r.p.m for a long time
  6. Samdallas214

    Samdallas214 Member

    I have a cheap 2 stroke china kit ( A Happy times) nothing extra just the basic kit. I pull a trailer home it took me almost 3 hours with out a problem my average trip is around 1-1/2 hours at a time without a problem. The only rest was at red lights
  7. roughrider

    roughrider Member

    I'll be riding my HT 225 miles in about a week and a half. I plan on doing a 100 miles or so a day. I'll be taking along quite a few spare parts and tools.

    I've heard how unreliable these engines are. But I am of the opinion that the reliability of the operator is senior to the machine. We'll see how my China girl does.
  8. Skyliner70cc

    Skyliner70cc Active Member

    I've run my china "happy time" motorized bike for 7-8 hours non-stop in very unforgiving conditions-mainly on forestry service/access roads and atv trails in the mountain. When I stop to tighten the front chain every 2-3 hours on my SBP shifter kit (really guys at SBP, you should fix this issue with a chain tensioner) I leave the bike running. I have two gas tanks and carry about 1.5 gallons of fuel and another 1/2 gallon in my backpack.

    Yeah, those china HT engines are junk :) Did I mention, until someone else steps up, I'm the unofficial high altitude record holder on a HT engine. Took mine over Cottonwood pass twice last year 12,126 feet AGL on top and a very long and refreshing ride and my china HT had no problem on the 10% grades! I did have to stop at 10,000 ft AGL and move the needle clip one notch to lean out the mixture.

    If you build it right, a HT will last thousand of miles. The only problems I have had were with my SPB shifter kit-front chain loosening and sloppy freewheel crank. My DAX engine is almost 5 years old-purchased in 2008- and runs like a swiss watch. My other engine is at least 3 years old and is an Ebay special.

    Oh yeah, I ride mostly full throttle up steep mountain grades at slow speeds.....that HT engine can get quite warm in these conditions.

    In 10 year of buying, building, and occasionally selling motorized bikes, I've had only two engine failures:
    About 7 years ago, I lost a piston/head assembly when the small pin in the piston that prevents the rings from moving fell out and allowed the ring to rotate and catch on an exhaust port (I now epoxy this pin in the piston if the piston has one-some HT engines don't)
    Second failure was wrist pin cage bearing failure about 4 years ago. My fault for not replacing it but it was a quick build.
    If you buy a HT and slap it onto your bike as is, then you will probably experience problems.

    The secret to engine longevity: 32:1 with 1/4 to 1/3 of your oil being pure degummed CASTOR oil. Nothing beats it for engine protection and though it burns a little dirtier, I've never had an issue with it as our engines don't have power valves in the exhaust.
    Last edited: Mar 26, 2013
  9. roughrider

    roughrider Member

    Brass Tacks


    But I got a question. You say, "32:1 with 1/4 to 1/3 of your oil being pure degummed CASTOR oil." Now, I KNOW people argue about this. I must have read 50 threads on the subject--among which your voice, Skyliner was strong. In the end, I went with the instructions that came with my kit--20:1.

    BUT, I've been blending Maxima 927 with high end synthetics at 5:1. I've had to jet the carb a bit lean to make up for the extra oil in the mix. But I am SO wary of using less oil! Your experience really trumps mine, but even so, I can't help myself. When I am ignorant, I just "follow the recipe."


    Specifically, Do you use straight Maxima 927 with no blending with other oils? That stuff is pricy, as I'm sure you know, though, I just bought two quarts of the stuff.
  10. V 35

    V 35 Member

    I'm running Opti 2 in 2 China Girls, so far, so good . During break in , I added some Synthetic Oil to the Opti 2 . I know a little about breaking in 2 strokes, having owned a bunch of them. Use extra Oil ! Make the first batch with about 20 % less fuel = richer mixture . Run the engine briefly, let it cool throughly first few runs. The heating, and cooling tempers the alloy, retorque bolts, and enjoy. Opti 2 is an interesting product, its formula is attracted to heat, so it nails the hot spots . Conventional lubricants tend to run away from heat, try it with a piece of tin, and a propane torch, pour down some oil, heat underside of metal, watch oil run away from heat.
  11. Skyliner70cc

    Skyliner70cc Active Member

    I purchase Sig degummed 1st press castor oil by the gallon. I then mix it with the cheapest 2 stroke oil I can find at Walmart. Sometimes its Yamalube, sometimes its Pennzoil, but most of the time its Supertech 2 stroke oil.

    How much oil I use and what ratio of castor/non-castor oil I use depends on the upcoming ride. If I ride on bike trails in the city then I burn 50:1 and use 20% castor. If I intend to ride very slow up steep hills in the mountains then I'll burn 32:1 and may go 50% castor on these blends. if I intend to go on a long cross country ride on smooth dirt roads and asphalt then I'll burn 32:1 and run 20-25% castor.

    I pay $23/gallon for pure castor and about $13/gallon for cheap 2 stroke oil.

    Optilube isn't anything special except its marketing gimmicks about being attracted to heat and it being having a eutectic mumbo jumbo blend. Its a very viscous oil and has very little solvent carriers versus other oils. Less solvent carrier means more lubricating oil and less you have to mix with gas for desired effect. There isn't anything special about it.

    If you are comforable with 20:1, go ahead and use what you want. I've neve run 20:1 even when my engine was new and never had any problems.
    Last edited: Mar 26, 2013
    roughrider likes this.
  12. roughrider

    roughrider Member

    Method? Science? Procedure?

    OK. Skyliner and V35? I'm listening. I appreciate your input!

    What I get is that you can't HURT your engine by running too rich. And by "rich" I mean your gas/oil ratio. At worst, you will just lose power.

    Unfortunately, the term "rich" also means your air/fuel mix. It's too bad our terms are confusing, but there you go. Yet, I get that Maxima Castor 927 is great ****e. (At $70.00 a gallon, it better be!)

    Backing off, getting more theoretical, if you are running a lot of oil in your gas mix, you are actually running a LEAN air/fuel mix, so you may need a bigger jet. I get that. I know. Not a lot of people do. That's what I have. At 20:1, I need a pretty large main jet for the engine to run smoothly at full throttle. This I know from many, many tests. I also know that running the extra oil keeps my engine a LOT cooler, but I lose top speed. I can feel the heat in the engine when I touch it, and I have a speedo. I'm OK with that. After all, it is better to finish last in a race than to not finish at all.

    So my current situation is an engine that runs well and cool, but maybe lacks top power. I know I can increase the speed and acceleration by running less oil and a smaller main jet. I can HEAR, and, FEEL, the engine whining and straining even when my speedo says, "Oh Yeah!"

    I guess what I'm asking is how to find out where the "sweet spot" is in a methodical way. I will not sacrifice reliability for speed. That must be accepted as given. Also, I'm needing to be persuaded that 32:1--or more--mix won't leave me stranded somewhere between Bakersfield and Los Angeles with an engine with a fried top end.

    Right now, using a 927 mix with good oil and a slightly rich main jet, I can cruise for hours in the flats without my engine overheating, and my spark plug is a nice, tan color. It ain't broke! Maybe I don't need to fix it!

    If anyone can recommend a nice, scientific way for a nerd like me to determine the correct oil/fuel mix, I'd love it.

    Last edited: Mar 26, 2013
  13. geebt48cc

    geebt48cc Member

    Rick, I would just try to play it safe. You said it all when you say, "It ain't broke! Maybe I don't need to fix it!" I've found that there are so many different combos of ratios????????????? The way I see it, as long as motor performs well, I would stick with the richer of the so many evils!!!~

    I'm sure thats the reason that you get so many opinions is there are so many different locations,temps,etc. Uno, just as long as your doing castor with a reputable synthetic ratio, your good to go!~ Really, when it comes to ratios, is all just good common sense.

    Double cheer,

  14. roughrider

    roughrider Member

    Chef vs Cook

    I hear you loud and clear, Glen. It's just that--now--I have a mechanical itch I need to scratch.

    I spent a few years of my life working as a cook in a lot of nice restaurants. Among the many fine cuisineers I worked worked with, I would only occasionally find the type who went beyond the "recipe." Why? Because he (or she) UNDERSTOOD the chemistry, the principles, the variations in ingredients and conditions... You get the idea. Such a one was a true chef, not just a cook.

    Now, see, this is a good example of that quality that gets beyond a cook. It shows understanding. I'm trying to dig that. That's all.

    At this point, I'm really just trying to figure out a methodical way to test various mixes without frying my engine. I have a "cookbook recipe." It works. But I am SURE I can improve on it.
  15. roughrider

    roughrider Member

    Just a little follow up...

    Thanks to the combined wisdom of the gurus here (Jaguar, Fabian, Geebt48cc,) I have managed to get the purrrrfect mix. My bike runs so cool now, I discovered that I had to run her really, really hard just to even get the motor hot. For a while, I was wondering why I seemed to be experiencing a loss in top speed and this odd fast then slow surge.

    Answer: Warm her up.

    Problem: She runs so dang cool!

    Relevant: How long can you run a two-stroke? Forever. But you gotta get her tuned. This Saturday, I'm taking her on a 40 mile trip in the hills up as steep a grade as the US offers. We shall see!
  16. ant797

    ant797 New Member

    good stuff thanks for the reply
  17. geebt48cc

    geebt48cc Member

    Rick,Rick, you go BIG GUY!!!!~ Sounds fun!~ Yeah, you'll do fine on trip. Key is, just to watch what everybody else does.

    Listen, sense bike is newer, do the obvious pre-flight stuff with bike. Remember to torque that head right at 12, in a Z pattern, PSI in tires, and lube /tighten chain. Man, wish I was going.................

    All the best!~


    PS- You'll also need to look into getting some SLIME for your tubs. Uno, a little more insurance on flats, when your out.
  18. roughrider

    roughrider Member

    Put a hundred twenty miles on her in two day's riding. Yep. Worked fine. Only glitch was the JBWeld sealing a gas tank leak gave out ever so slightly. I suspected my fix would not work, and it didn't. I've been rubbing bar soap around the stud where the leak is until I finish making the rear rack for my other tank. That bar soap trick WILL get you down the road. I learned that from my brother-in-law on this trip. Man, I just love folk wisdom!

    I have a story I'll be posting about the trip. Took a lot of pictures. Got some pictures of a lightning storm!

  19. Mikenike

    Mikenike Guest

    How the hell are you pulling a trailer on a bike, even with a cheap motor? I call BS!