Every time I ride it something breaks! Grrr...

Discussion in 'Rack Mounted Engines' started by heathyoung, Oct 16, 2008.

  1. heathyoung

    heathyoung Member

    Hey all... I'm sure everyone has this issue but anyways... Maybe I have worse luck :(

    Setup is an Australian sourced (from china?) Gebe knockoff, with a 31cc ~1hp (700W eep!) 4 stroke, 16 tooth drive pulley (to keep rpm low so it doesn't exceed 200W limit).

    So far... Belts come off regularly - alignment is OK, tension is OK, problem comes from the lack of a dynamic tensioner (as per Gebe design). Made up my own dynamic tensioner with two bearings, some scrap metal, a spring and some bolts and nylock nuts - solved.

    Stupid engine has to be tilted back too far, and the fuel filler leaks fuel out as a result. Made up a cradle from scrap aluminium and turned it around so the filler faces the front of the bike, not the rear. Tygol hose is expensive, but good stuff!

    Sum-ting-wong brand sparkplug dies without warning, replaced with NGK, no problems. Revs better.

    Backfire blows airfilter housing off in traffic, gets run over by a truck, unrecongisable now. Replaced entire housing with cheap pitbike K&N knockoff + 40mm plumbing end cap. Noiser, but revs better.

    Fuel filter picks up air (very bulky design) when tank low. Replaced with smaller 'whipper snipper' type.

    Bolts always fall off/bend. Replace with good quality high tensile bolts, with lock washers etc and nylock bolts.

    Sheared off weld on clutch going downhill. Really poor penetration on weld. Stupid drive pulley kept unscrewing itself on the way home, had to keep on the throttle and brake to stop it. Got the local exhaust guy to weld it back on, much better job.

    Positives: Gets me to work on time with some exercise, costs about $3.00 per week in fuel as opposed to $50 per week in the car. Clutch is holding up very well, expected a lot more wear the way I ride.

    I'm not sure what else is left to break :p

    Negatives: very little power due to poor gearing - I'm going to get an 11 tooth I think - to better suit the motor and the very steep hills I have to push the bike up (grrr...) Engine is cantakerous, always starts, but when it gets good and hot, tends to ping (even on 98 octane) and leans out + misfires.

    'Shoulda bought a gebe with a tanaka, or built my own (which is what I am in the process of doing - slowly - probably using this engine and a CVT).

    Anyone else have as much luck as me?

    Heath Young

  2. AlphaGeek

    AlphaGeek Member

    Sorry to hear about your experiences. Sounds like you bought a hobby and not a solution.

    As a thoroughly biased GEBE/Tanaka owner, I think you were exactly correct with this statement in your post:

    That said, hopefully you're through the worst of your component failures so you can focus on getting things running properly. From what I've read here and on the other motorized-bikes forum, owners of the low-end Asian motors do eventually reach a point where they get things running to their satisfaction. And then the seasons change and you have to adjust the carb again. :)

  3. Mountainman

    Mountainman Active Member

    that's a LOT TO DEAL WITH !!!!!!!!!!!!!

    for the COMMON MB man or woman


    not sure that if most knew this before hand -- they would buy

    because many only truly want to do one thing --

  4. Slay

    Slay Member

    What the **** is a GEBE knockoff?????
  5. vegaspaddy

    vegaspaddy Member

    Dont Even Ask !!!!! Slay
  6. heathyoung

    heathyoung Member

  7. seanhan

    seanhan Member

    Well I don't know about the GEBE knockoff , but there Kill Switch looks cool !!!!!
  8. heathyoung

    heathyoung Member

    Its probably the most reliable part of the kit actually. Cable's too short though...
  9. loquin

    loquin Active Member

    BTW - a 1 HP motor is about 750 watts, no matter what the RPM...
  10. heathyoung

    heathyoung Member

    Not according to any dyno graph for an engine.

    Engines produce pretty much the same torque across the RPM range, but the power goes up along it - the power output of the engine (whilst obviously not linear) will increase with RPM. An theoretical engine that produces 700W at 7000 rpm will produce 200W at 2000 rpm.

    Restrict the engine by loading it up (use up all the torque so it cannot rev any harder even at WOT) and you get yourself a power restricted engine. Fix up the gearing so it revs better, you remove the restriction. This is the reason for the very silly 16 tooth gearing - it restricts the engine power something awful (but it does go well down hills :)
  11. heathyoung

    heathyoung Member

    Now I broke a belt on the way to work :(

    I did find out that if you cut through the middle of two teeth, stick them together with superglue and reinforce with gaffa tape you can still use the belt :)
  12. heathyoung

    heathyoung Member

    Replaced the diaphragm in the carb, no more splutters... BUT.

    Sheared the bolt out of the clutch again, it flew out at great speed and hit a car - driver wasn't happy, but understood when I told him the country of origin of the kit...

    I've had it, seriously... A CT110 looks like more intelligent transport than this thing.
  13. bluegoatwoods

    bluegoatwoods Well-Known Member

    Thinking about it, I had a car once that sounds a bit like this. A '79 Thunderbird. I won't bother with details; you can imagine.

    It's the only car I ever abandoned.
  14. fetor56

    fetor56 Guest

    I talked with a guy a few weeks ago that had one of these Black Star setups & he had to do extensive modifications to get it working properly,so your not alone...welds break,bits fall off.Bad design,bad materials,bad model maybe & he wasn't impressed.
    I've gone for the Dax Titan system & it's been great(with my own mods).......even if i had a GEBE i'de still modify it.
  15. heathyoung

    heathyoung Member

    Its pretty badly designed - **** welds on the clutch bell, I ended up removing the circlip, belting out the bell from the bearing and drilling though the bell and shaft and putting in a cotter pin (3mm) - its lightening itself (bits keep falling off).

    Th carb is a joke, 10mm (!!) and the ports are only 10mm so going bigger is pointless.
  16. EasyHardLivin

    EasyHardLivin New Member

    oh god... i got similar problems with mine. i got a 69 cc motor from CHINA... Ironically it's always other things that causes problems, not the motor itself... Clutch, carb, bolts breaking, bla bla... ya seems like more hassle than fun with these chinese pieces of ****.
  17. heathyoung

    heathyoung Member

    Sigh... I've officially got the ****s with it now.

    It sheared the cotter pin on the way to work this morning, and I started tapping a thread through it... and the TAP broke :(

    So not very happy... I'm going to complain to the seller, this is not fit for purpose, not fit for sale. Serious junk.

    I'll gladly send the whole lot back to them.
  18. fetor56

    fetor56 Guest

    Do that(tell the seller)...he may do something about it or he may not but atleast u would have tried your best.
    Good luck & keep us posted for the Oz ppl. :)
  19. heathyoung

    heathyoung Member

    The seller is very unlikely to do anything I think. I've sent emails regarding all of the problems I've been having, I have just about fixed the clutch problem I think... Ebay looks like a good place to get rid of it.

    Its ****ting me off how much I had to fix on it though - no-one with the happytime frame mounts seems to be having as many issues...