Schwinn Searcher, Centrifugal Clutch, Pull start, Shifter Kit Review

Discussion in 'Photos & Bicycle Builds' started by Skyliner70cc, Feb 2, 2009.

  1. Skyliner70cc

    Skyliner70cc Active Member


    Schwinn Searcher:
    :icon_cry:price of this bike has increased from 169 to 219 plus tax. New versions of this bike have a different frame geometry that made it difficult for me to use my traditional front mount system with a sick bike parts kit. The new frame has less room for an engine and my carb didn't fit (it hit the top of the frame). Another drawback of this new version of the Searcher is that it no longer has the Megagear 34 tooth 1st gear sprocket. This is almost mandatory for Colorado riding. Another drawback of the Searcher is the worthless kickstand (on both old and new versions). It flexes and fails.
    First Searcher I bought had a crossed threaded crank. I could not install the new crank parts from the SBP shifter kit.

    Boy Go Fast Centrifugal Clutch (dual start-pull start) engine:
    For 175 dollars shipped I got: A dented (with paint damage) gas tank, a throttle cable that was too short, a terrible paint job on the engine that was scratched up and uneven, and a carb that leaks fuel when engine is not running, and a very crappy muffler (lousy chrome, downpipe was bent and dented in the curved section, and welding that was done by a 3rd grader. The welds on the can are so bad that I used another muffler from another vendor. BGF would not respond to any of my emails and I am contesting this purchase for a partial refund to cover the many parts I replaced.
    The engine has good power so far (30 minutes total time), the carb leaks fuel when engine isn't running (WH Carb), and the centrifugal clutch was engaged the entire time until the pads/shoes on the clutch got bedded in. Idle must be kept very low as to not engage the centrifugal clutch. It works as advertised and not having to pull a clutch lever in when coming to a stop is VERY NICE. The clutch engages rather quickly so I do pedal to 3-5 mph before I roll the throttle on. The pull start is AWESOME. It took only 2 pulls to start this new engine and it was so easy to start! Unfortunately, the pull start rope failed after 6 pulls and I will need to repair it. This engine has dual start so I am still able to start this engine with the pedals.

    Shifter Bike Kit:
    Works as advertised but for its cost, I wish that I didn't need to file and sand the jackshaft to make all of the components that slide onto it to fit. I wish SBP would have this done on the factory. This is a real unnecessary PITA.
    JB weld the small aluminum 90 degree bracket between the right side place and the back engine mount plate. After JB weld cures, then drill out the holes and reinforce with the screws provided in the kit.
    You will need spacer washers with the BGF auto clutch engine between the left drive sprocket and the left engine shifter kit plate.
    Use epoxy putty and fill in the spaces on the rear frame mounts (muffler clamps). This allows more area to contact the frame tubes and less chance of damaging the frame tubing when tightening the mounts.
    Use corrugated plastic to place on the vertical seat frame tube so rear mount shifter kit mounts do not scratch the paint when moving the engine up and down to tighten the chain.
    File the keys that are used on the shifter kit gears and slotted jackshaft so that things can be slid back and forth easily.
    Do not ride the bike without the chain jump guard. I was in ahurrry and my chain jumped in first gear and got wrapped around the crank. The nuts on the freewheel catch the chain and make it very difficult to remove. In future installs, I will reverse the direction of the freewheel nuts and have the nut sticking out by the crank. No nut for chain to catch on.
    I have a 7 speed cassette on my bike and placed an extra (fairly thick) washer on top of the spacing nuts on the freewheel so I would have chain clearance in 7th gear. My last searcher build didn't allow me to use 7th gear because the chains rubbed.

    For the clutch lever, I used a three piece gear (front derailleur shifter) that was combined with a brake handle. It takes 3 clicks to fully engage and release the clutch. A great option to have with an auto centrifugal clutch but not something I would put on a regular kit because it cannot be engaged quick enough.

    Front Engine mount on the BGF engine is wider than the rear mount. I could not use the rear engine spacer as a spacer for the front mount as I have on other builds. Also, I had to drill out (widen) the livefast motors mount holes for their oversized mount system to make things work. All muffler clamps and front mount u shaped brackets had heat shrink tubing placed over the clamps to protect the paint. The lifefast motor's bracket coudln't handle the torque and was replaced with a 1 7/8ths muffler clamp bracket that could handle much more torque (i like things nice and tight).

    More to follow as I can recall from memory.
    Last edited: Feb 2, 2009

  2. Ghost0

    Ghost0 Guest

    Nice write up, very detailed. I liked your idea about tacking the bracket in place prior to drilling. We could put the flats on the shaft but it would add about 15 to 20 dollars to the kit. As you mentioned on the front chainrings it would be better to have the nuts outside rather than in but there is not enough room between the crank and chainrings for the locknuts. Now lets see some photos of the beast.
  3. eltatertoto

    eltatertoto Guest

    well you just built my dream bike...too bad i have to sell all my stuff lol
  4. Skyliner70cc

    Skyliner70cc Active Member

    Its my dream bike too. The only thing it needs now are the following:
    a. speedometer
    b. A freehub instead of the threaded on freewheel. The threaded freewheel is very weak and I've had 3 fail on me-2 with shifter bikes and one from just pedal starting a single speed bike.
  5. byronmill

    byronmill New Member

    How does BoyGoFast dual start work?

    I have some question on how the dual start functions. I sent off a message to BGF on eBay, but his response does not make much sense. Response was "just pedal fast enough and the centrifugal clutch kicks in and the engine starts". That does not seem mechanically possible. Is there some mechanical override or bypass of the clutch that would fully engage the drivetrain with engine crankshaft while pedaling in order to start the engine? Any feedback would be appreciated.

    Seems like he sells a lot of these engines. Have others continued to have the same problems and dissatisfaction that Skyliner spells out here?

  6. Skyliner70cc

    Skyliner70cc Active Member

    I pedal start or pull start each of my engines that have a centrifugal clutch. A compresison release sure would help the pedal start.
  7. byronmill

    byronmill New Member

    Skyliner, do you have any information, pictures or details on how the pedal start overrides the centrifugal clutch or you just know that it will work by pedal starting. You mentioned compression release on pedal start. Why would that be an issue on pedal start and not using the pull start. I would have thought it would have been the other way around. Seems like you could get a lot more force applied by pedal start than the pull cord, especially if you got the bike moving first.
  8. Skyliner70cc

    Skyliner70cc Active Member

    No, sorry I don't have the details for you. All I know is how I start my two bikes that have the centrifugal clutch. I have high compression slant head and it takes a lot of body weight pushing down on the pedal to get the motor spinning for a start. I'm fortunate that my engines start almost instantly. Pull start is easier to start than pedal start but rarely use the pull start anymore....they break easily.
  9. Wheres my dog

    Wheres my dog New Member


    Just a note in the interest of safety... I had a Schwinn Searcher as well, and had a bad wipeout one time when the headset came loose.

    As much as I ever tightened it and kept watching it, it always came loose again!

    Maybe they changed the headset to a better one, but just a word of caution for you sir.