More Problems. Start from Scratch or Lay Down More Money?

Discussion in 'Whizzer Motorized Bicycles' started by Nolan, Jul 21, 2009.

  1. Nolan

    Nolan Member

    So I took my whizzer down local motor shop because I had past my knowlege of engines. The guy there fixed the timing and some other stuff, now it stays running and can go full speed on flat, but it doesn't have enough power to go up hills as the compression is 60-70 lbs.
    Valves passed and air test so that leaves the cylinder. He mentioned there is a chance it could be fixed with new rings, but may also need to be bored out for a new piston and rings.
    Motor still has a rattle from the crank or arm and only does it when motor has little or no resistance, such as coasting down a hill or when on a high idle. Flywheel seems to be spinning straight, it doesn't rub on the magneto if it is set close.
    I have now spent around $1100 on just the engine alone and almost killed my desire to own it.
    The question is, should I just buy the next professionally restored engine I come across and sell this one off for parts on ebay, take it to some one who can professionally rebuild it, or keep putting money into it until it runs? It is almost halfway though summer and won't have time to work on bikes when school starts.
    Last edited: Jul 21, 2009

  2. RdKryton

    RdKryton Active Member

    Hi Nolan
    A little history may be in order here. Is this an older engine? 40's or 50's? 60 to 70 pounds is too low for the compression. The compression should be tested with the throttle wide open while peddling the bike on the stand. Did your mechanic check the head to make sure it is not warped. The rattle scares me though. Quenton Quenther should probably take a look at it before you sink any more money into it. He is a long time member here and is easy to contact. He has forgotten more about Whizzer engines than most "experts" know. He rebuilt the H model engine that I have. PM me if you want his contact info.

    PS Don't give up on it. A good running Whizzer is a fun ride and it will always turn heads. I love both of mine.
    Last edited: Jul 22, 2009
  3. WZ507

    WZ507 Member

    Whizzer Fix


    With the ignition system squared away, you have three potential areas to deal with to obtain the drivability you seek; 1) a good valve job, 2) a good piston/cylinder fit with fresh rings, and 3) a properly fit connecting rod/crankshaft assembly.

    A satisfactory valve job simply requires tight valve guides, and good valves and seats ground properly.

    The piston/cylinder assembly should be fit at about 0.003-0.004", but can be as loose as 0.006" and still provide excellent performance. If it had 0.006" clearance, I'd clean it all well, hone it lightly, install new rings and it would perform perfect for your needs. Used pistons are also available and inexpensive, and one in good condition would work fine for you.

    The knocking you hear is likely from the connecting rod fit on the crankshaft journal (assuming you have an insert style crank). It is very common for the bearing inserts to pound out and once worn, they behave as you described - under load they are silent but when up on cruise and loaded lightly, or when decelerating with no load they knock. The knock is more annoying than dangerous, but ultimately needs to be remedied. This could possibly be resolved by simply replacing the bearing inserts if the crank is in good condition (very common fix). If not the crank must be reground undersized, and a complimentary sized bearing set installed.

    Unfortunately it all costs money to do, but when you're done, at least you know what you've got. Buying a "rebuilt" engine on ebay is buying a "pig in a poke", and there is no way to know what you are getting.

    Have you invested $1100 on repairs alone?
    Last edited by a moderator: Dec 15, 2015
  4. Nolan

    Nolan Member

    Its a Early J Engine with the high compression head. I mentioned the full throttle part to the guy testing it. He opened it up to fix the timing and the markings looked as if they were nearly sanded off so it might have been rebuilt with old parts at one time.
  5. Nolan

    Nolan Member

    $1100 total about $400 in new parts so far. Engine was $835 when it got to my door, came with a tank, sheave and mounts which were all spray painted over rust. And belts that were all wrong anyways. So pretty much it was a bad buy right off the bat, but I was still in school so I didn't get it on a bike until two and a half months after I bought it.
  6. Mountainman

    Mountainman Active Member

    it appears that somebody may have gotten you

    yes it appears that somebody may have gotten to you
    all the compression tests that I have ever done or seen done
    were just with
    turning over the engine a couple of times at verly slow speed
    such as when done on a car -- disconnecting coil wire
    don't want the THING starting
  7. Nolan

    Nolan Member

    So a bore is around $40, what do pistons, rings, arms and cranks cost? I'm gonna have to open it up and see what I actually need.
  8. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi Nolan,

    Compression on a good "J" motor should be between 90 and 115 pounds. The hi fin/ high compression head might bump the numbers up a little. Insert crankshafts are normally less noisy than the needle bearing versions, and less expensive to rebuild.

    The price of the parts will vary greatly between different vendors, but if you need info on options, just contact me at, or via cell phone 252-475-0406.

    I have a large supply of both vintage and new edition Whizzer parts in stock if needed.

    Have fun,
  9. btr

    btr New Member

    Keep Hope Alive

    Nolan I'm getting a new cylinder from Mr. Guenther Monday. He's the man! I tried to buy a high-fin milled head from him other day. He told me to wait till I put on the new cylinder first, then decide because he's looking out for me not to spend too much. He's been helping me save my brand new 2008Ambassador. I know what you're going through, I've been going through it for past 7 months. Last night I took it apart again & all day today I was running around to 3 different NAPA to get the shorter side belt I needed, just another typical weekend for 2008 Ambassador owner who still hasn't given up. Photos taken last night @ 1:30 AM. By the way, this is not only my first Whizzer but also my first motorbike/motorcycle/Board Track Racer.

    Attached Files:

  10. btr

    btr New Member

    Whizzer metal

    Got the oil stick today Mr. Guenther. Thanks
    Here's a pic of the latest metal breakage on my bike. Happened yesterday 4 miles from home when I hit the start button. Ordered a new one this morning and wondering what's going to break next. Here's a list of things that either fell off my bike or broke so far.

    Rear Fender Tab (Prerequisite for riding) made a new one
    Air filter cover & top of air filter (found it on a street)
    swing arm top center bar and reflectors (found it on a street 2 miles from home & realized I rode 150 miles without it)
    Speedo cable (lucky wasn't the brake cable)
    motor cover rear bracket (made a new one)
    Oil stick (My fault, I dropped it 10 inches off the ground)
    Starter mounting bracket

    Just when I was having fun again.

    Attached Files:

  11. Nolan

    Nolan Member

    Well, it look like its gonna be around another $250-300, I'm getting the cylinder bored, new piston, rings, gaskets and crank and rod assembly. If I can those parts quickly I should have it done in time for the Whizzer ride at the Iron Ranch swap meet. In situations like this I try and see it as paying for a class, so I'm trying to learn as much as possible from the people helping me out.
  12. bill green

    bill green Member

    Hi Nolan If your trying to make Al Schermans Iron Ranch Are you in the portland , Vancouver area ....Bill Green Vancouver Wa 360-601-4486
  13. Nolan

    Nolan Member

    I'm up in Bellingham so its a bit of a drive, but there aren't many good swaps near by so its the only one I usually go to.
  14. bill green

    bill green Member

    Hi Nolan I look forward to seeing you there...Bill
  15. Nolan

    Nolan Member

    Thanks everyone for the help, I just got the bike running today and its perfect. Heres the full rebuild list. From Memory Lane I got a new magneto, piston (.040 over), rings, gaskets. From Quenton I got a crankshaft and rod assembly. I had to get a custom wrist pin bushing made valves lapped and cylinder bored out. I managed to get it all together myself and had fun baking bearings and freezing crankshafts so they'd fit.

    I'm not supposed to run full throttle yet, but I couldn't help going full on one run down the street. It pretty much it flies, probably getting pretty close to 40 MPH thanks to the high compression head and new piston.

    I would like to say that you should be vary careful buying vintage engines off of ebay. I got mine from a member with username flywheelfarm, who claimed this engine was fully rebuilt and ready to run ($800 with some other parts). It turned just about everything possible was wrong with it and it has taken me $600 and five months to get it running right.

    Pictures and video soon.
  16. RdKryton

    RdKryton Active Member

    I'm sorry you got slammed on the original deal but I think it's great you got it sorted out now. We have some very very knowledgeable Whizzer experts here. Quenton has probably forgotten more about Whizzers than I will ever know. Can't wait to see the pictures and video.

    Last edited: Sep 22, 2009
  17. Nolan

    Nolan Member

    this is how it started...
    <a href="" target="_blank"><img src="" border="0" alt="Photobucket"></a>
    I'm sure someone has done this before, but running the H controls upside down gives a huge advantage. you can adjust the throttle just like a twist grip and you never have to take your hand off so its much safer.
    <a href="" target="_blank"><img src="" border="0" alt="Photobucket"></a><br /><br />

    <a href="" target="_blank"><img src="" border="0" alt="Photobucket"></a><br /><br />
    the brass tailpipe end just came from the hardware store, to match the brass brazed joints on the frame.
    <a href="" target="_blank"><img src="" border="0" alt="Photobucket"></a><br /><br />
    I got this front brake off of ebay for 20 bucks, its off of a Norwegian bike, unfortunately it doesn't have that much braking power. the little stars are to take up the space around the spokes cause the holes are to big.
    <a href="" target="_blank"><img src="" border="0" alt="Photobucket"></a><br /><br />
    Light should be working soon, its an early 30's Rollfast
    <a href="" target="_blank"><img src="" border="0" alt="Photobucket"></a><br /><br />
  18. RdKryton

    RdKryton Active Member

    Very very nice. Does the copper tip on the exhaust restrict it much?
  19. Nolan

    Nolan Member

    It doesn't seem like it since I have plenty of power. But it does give a little more pop to the exhaust sound.