Another copy '.' cheapest yet... 25cc..propane? eh?

Discussion in '4-Stroke Engines' started by HeadSmess, Feb 3, 2011.

  1. HeadSmess

    HeadSmess Well-Known Member

    so, yet another search has revealed this wee beasty...

    after much needling and messaging, ive managed to get this guy to ship two to AU... :bowdown: a LOT of needling... it still comes to a reasonable price, compared to buying, say, a honda... with no delivery....

    propane could be funky....looks like ill be changing carbs or rigging up a "filling station"... helps having a 1000lb bottle around the place :)

  2. Silvaire

    Silvaire Member

    You probably already know this, but these Lehr trimmers use a Chinese built copy of the Subaru EH025 engine. They also have a propane fuel system. I don't know if the Lehr engines differ from the Subaru engines internally in design though. Propane engines often have higher compression ratios and more advanced ignition timing.

    I have 3 or 4 of these Lehr trimmers as well as one of the Lehr blowers. I am fairly impressed with the engines, although they are not as nicely finished as the Subaru. Much of the rest of the trimmer is poorly designed though, and Lehr has had a lot of customer issues. Sears used to sell Lehr trimmers with a Craftsman label, but they had too many of them returned so they discontinued them.

    GoPed offers a scooter with this engine, and calls it the ProPed.

    Way down my project list, I'd like to try putting a Lehr propane carb onto the larger Subaru EH035. It will bolt right on with no modifications. First though, I'd want to measure the compression ratio of the Lehr engine to see if they have a higher compression ratio.
    Last edited: Feb 7, 2011
  3. HeadSmess

    HeadSmess Well-Known Member

    yep, engines turned up today, and there you are... subarus. i didnt know until then and i may have known earlier if id read this... cant say we get much choice in AU... and info? i searched...

    at a visual level, im giving em about an 8/10...pretty good, but havent seen an actual suby to compare...

    pretty happy with em though...make a cute pair :) and without the shaft and clutch, should be running just as smooth as a leaf blower. ie, no issues... :) ? and at the price theyre at...

    yet to get any gas to start em up, but love the setup! very cute....wonder if pulling the "carb"(mixer) apart is a good idea? lol
    Last edited: Feb 13, 2011
  4. Silvaire

    Silvaire Member

    Not Subarus - COPIES of Subarus - made in China by/for Lehr!

    These are neat little engines, but I wouldn't expect too much for power from them though. The Subaru EH025 (gasoline) is rated at 1.1 hp, and GoPed rates the Lehr engine on their ProPed as being 1 hp.

    I don't think I would try doing anything with the fuel system other than just running it as it is. For occasionally used yard equipment I really like propane. Although the instructions say to remove the propane tank when not in use, I just leave mine on all the time. Only on one trimmer did the propane leak out, and that was over a matter of several months. Even after sitting for a month or so, it's just switch it on and give it a couple of pulls and its running. Not having a gummed up carb to disassemble and kit after it's been sitting over the winter is a real pleasure.

    If you want to go with a friction drive, Staton offers a kit that will accept these engines:

    This kit, with the 54mm clutch drum and either the 7/8" or 1" roller is a simple bolt on and go for the Lehr engine. The only thing you will have to fabricate is a throttle cable to fit the slide type propane carb.


    I forgot to mention, but you can buy (or make) an adapter to refill the small 1 lb. disposable propane bottles from a larger tank. There is plenty of info to be found on the web as to how to do this. For a propane powered motorized bicycle it wouldn't be cost effective to be buying and throwing away 1 lb. disposable bottles when they would probably only take you about 20 miles or so on each bottle.
    Last edited: Feb 17, 2011
  5. HeadSmess

    HeadSmess Well-Known Member

    yeah, yeah, copies, i know :p

    anyways, ive fitted one up as a brushcutter anyways...had a shaft or two handy, didnt i? nice... not as nice as the neighbours honda, but hella cheaper!

    im never ever going back to friction drive, no siree bob! been there, done that, 15 times over the years... now its gears,chain, pulley.

    on one im using the clutch and gears from a 1/5 rc buggy, hardened steel, bolt straight on, just have to whack some (accurate) holes and a bearing in a piece of alloy, fit a sprocket... done.. then find another frame...

    propane fillings a breeze. as i said, i have a 450kg bottle handy... 450kg! 1000lb...

    at 20 freakin dollars a bottle at the hardware, theyd wanna be refillable!

    wondering what using propylene would do? they have propane and propylene, 'lene burning hotter... gotta get propylene anyways cus thats the only kit available which is cheaper than buying a 2nd bottle n torch seperately...

    im hoping, maybe... the manual says 2 hrs runtime... id assume thats while using, not sitting there idling... with my current setup, at an average speed of 50km/h... do the maths. and you do idle on the down hill runs... ive only ran one for ten minutes or so... ill find out sooner or later!

    else i may be looking at a slightly larger bottle... :p
    Last edited: Feb 24, 2011
  6. HeadSmess

    HeadSmess Well-Known Member

    :whistling: hows about using a gas bottle as the frame? :whistling:
  7. Silvaire

    Silvaire Member

    I'm sure you could, but why? The small disposable bottles are a convenient size and one or two or possibly more (either the skinny ones used with touches or the fat ones used with camping products) can be mounted within the frame triangle or on a rack. They can then easily be exchanged with full bottles that you have previously refilled and have on hand. Unless you have a filling system using a pump to refill the bottles, you pretty much have to put the bottles in a freezer first in order to get them to take a full 1 lb. charge. Lastly, most propane vendors have a minimum charge for filling anything, and going to a station for a propane fill up is a rather lengthy process compared to filling up a tank with gasoline.

    Anyway, let us know what you end up doing with your Lehr propane engines.
  8. Htown

    Htown Member

    Weld a tank into the main tube
  9. HeadSmess

    HeadSmess Well-Known Member

    :p i was being silly.... having two bottles, one always filled is the best idea :)

    but now my heads hurting...

    looking at a 2 speed auto shift...

    hardened gears, all set up, these engines can sometimes exceed 4 horses....or about 4 times the power that this little LEHR can make...

    im just concerned about the ratios... 3.353:1 shifting to 2.22:1 is pretty abrupt... these buggies can spin the wheels, no probs, but on a pushie... ??? i sense bits breaking possibly... or needing to be silver soldered together...

    i wonder if its worth the money? machining all those parts is way too much work, while adapting existing stuff is easy :)... and i could always have the first ratio changed...

    my maths work out that with these ratios (after the final redux) id hit 35km/h no probs, shift and hope for about 65km/h in 2nd gear....