Whizzer ignition timing.

Discussion in 'Whizzer Motorized Bicycles' started by RdKryton, Apr 16, 2008.

  1. RdKryton

    RdKryton Active Member

    Hello all
    I have been doing some reading about advancing the timing on a Whizzer. It has raised a few questions for me. I believe I can do the mod without much difficulty but I am wondering if it is really worth it? Do you gain enough performance to make it worth the time and effort? Does it help the top speed or bottom end torque? I hope Bill and Quenton chime in on this.
    Thanks

    Jim
     
    Last edited: Apr 16, 2008

  2. KilroyCD

    KilroyCD Active Member

    Jim, your bike is already scary fast. Are you trying to keep up with Quenton's new engine? :lol:
     
  3. RdKryton

    RdKryton Active Member

    You never know. lol Not really but if I can increase low end torque, I'm all for it.

    Jim
     
  4. bill green

    bill green Member

    Hi jim Ive never advanced my whizzers timing If its like mose 4cycle one lungers when you advance timing you get better top end and drop torq this is down to fuel octane,cam,and compression.so I think Im saying (I dont know).try asking Quention.... BILL I dont Know Green
     
  5. RdKryton

    RdKryton Active Member

    LOL Thanks Bill
    I have not read anything that says what the advantages are of advancing the timing. Maybe Quenton will offer some insight on this tomorrow.

    Jim
     
  6. bill green

    bill green Member

    JIm there is A post on the net about A guy around salem oregon that ign. adv.was part of his build. Bill Green
     
  7. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi Jim,
    Everything you wanted to know about Whizzer ignition timing. First the article everyone is referring to was written by a friend of mine, Ron Dow [Texas]. Part of the motor was modified by Raceway Products in OR, and the balance by Ron Dow. The motor in question was an original WC-1, but never won any competition. Shortly after the article was written Ron contacted me to build a NE motor, and he said it was the fastest Whizzer [flat head] he had ever tested period. I watched this motor exceed 75 MPH on the "Roller Road" [speed dyno] at Metroplolis, IL several years ago [before they changed the "load" on the Dyno to slow the top speeds down by 10 MPH]. I have advanced the timing from 14 degrees [stock] to 41 degrees BTDC, and unless you have a lot of special changes to your motor the advanced timing will in fact degrade the power at lower RPMs. Another problem is how to advance the timing and still have fire, the flywheel must have a magnet in the correct position or the spark will drop. It is possible to move the trigger plate to 23 degrees BTDC without a major effort, but you won't notice much if any difference, because it is only 9 degrees advanced from stock. Remove the trigger plate, move plate counterclockwise 7/16" of an inch, drill a new hole in the flywheel and thread to 5 MM. If you exceed 7/16" the magnets aren't lined up correctly for maximum fire, and the motor may become impossible to start & idle. I made several special plates to mount the trigger in a different location and slotted the plate so that I could adjust it. And I made sure the magnets are in the right location in refference to the trigger. It is hard to tell [without a Dyno] if the timing change make much difference, however another friend of mine [Gerd Lowack] mounted 2 plates, and 2 trigger assemblies and has a switch to alternate between the two, and he says it makes a big difference, but his motor is modified to the max. His motor is bored [major], camshaft is cut & twisted to alter the center lines, special head, mikuni carburetor, copper head gasket .010" thick, and major port work.
    If you want more information on this subject, just ask.
    Have fun,
    Quenton
     
  8. When the thread started, I thought the question was about advancing cam timing a tooth. I have milled .070 from head, opened intake restrictor, ported exhaust & advanced cam timing a tooth. the top end power is down right great, however until I get to 10-15 mph it is gutless. I wouldn't have a problem with this, but when coming to a steep hill & can't keep speed up it is a problem. My question is, will I have more low end power if I set cam timing to spec? I even have the "crappy" aftermarket auto clutch that has a lower ratio. (the one quenton loves so much.lol.)Top speed however is just about 45mph. I just can't belive how much power I have in the upper rpm's compared to lower rpm's. I would like to get a happy medium, but I still want as much top speeds as possible. Somehow I would like both! Didn't mean to hijack thread, but thought it would be helpful to thread. Thanks, Dan
     
  9. go-rebels

    go-rebels Member

    Hi Quenton,

    Can you post a pic of the timing gears showing stock and one tooth counterclockwise? When You pull the timing cover off and pull the cam out of the cover, how do you know the original location (rotation) of the cam given all the differences between stamped dots and dashes?

    Also, can you advance by TWO teeth or is 1) Low end torque is adversely affected, and 2) Does Pickup need to be moved as you described below?

    Stock = 14 BTDC
    One Tooth = 23 BTDC (no pickup movement needed)
    Two Teeth = 32 BTDC (???)
    Three Teeth = 41 BTDC (Big modifications required!)

     
  10. RdKryton

    RdKryton Active Member

    I know this is an old thread but it has new life so I will share the results of my testing. Let me start by describing my engine and the mods that have been done.
    2000 WC-1 upgraded to NE5
    Hi-Lift cam advanced 1 tooth.
    Head milled .070 and reworked by Quenton.
    Cylinder decked and valves recut and liquid tested.
    Minor porting work.
    26mm carb with a 110 main jet.
    Aluminum intake spacer modified to 1/2 thick, polished and tapered for the 26mm carb.
    Hi-Flow exhaust insert.
    The engine ran very well with the timing in the stock position. 14 degrees BTDC.
    I did the timing mod moving the timing to 23 degrees BTDC.
    It did not take away from the low end at all. I actually gained power all through the rpm range. The largest gain observed by me was mid range and top end. I now pull hills gaining speed when before it would just hold or slowly loose speed. The bottom end did gain a little more grunt but the best gains are from 2500rpms and higher. The modest timing advance is a mod that is easily done and if you don't like the results it is just as easy to undo. I believe I got such good results with this mod is because the engine has many other mods.
    Good luck.

    Jim
     
    Last edited: Jan 8, 2009
  11. go-rebels

    go-rebels Member

    What about advancing two teeth???
     
  12. Kep1a

    Kep1a Guest


    That would advance the valve timing only and likely make it an engine that will only idle at 1500 or higher and not be in its power range until 4500rpm or higher. But only if you advance the ignition timing on the crankshaft trigger to match the valve advancement. Not a good idea at all IMHO!

    Kep1a
     
  13. RdKryton

    RdKryton Active Member

    I don't know what effect that will have. I'm sure Quenton will chime in here with some information. It may very well make the engine impossible to start. I just don't know. Sorry

    Jim
     
  14. go-rebels

    go-rebels Member

    From my earlier post... can anyone post a pic of the gear alignment?
     
  15. Kep1a

    Kep1a Guest

  16. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi Go,

    Don't do it! Only advance it one tooth. For a while a couple of Whizzer dealers were suggesting 2 teeth, but the end result was less than stellar. Because of the piston cycle, the intake was open too soon and destroyed the intake charge pulse at low to midrange. The top end paid a price also with almost 800 RPMs less.
    Even if you advance the ignition timing it won't work correctly.
    A few facts concerning advancing the ignition, it can be easily altered from 14 degrees BTDC to 23 degrees BTDC. If the trigger is moved past the 23 degree BTDC, the magnet sync will decrease the necessary voltage and will lower the spark [or totally remove the spark]. In order to advance the timing, simply remove the trigger plate on the flywheel, move it forward [counter clockwise] until the rear edge is now covering 1/2 of the original hole. Mark the spot, drill & tap [5 MM threads]a new hole, insert screw thru plate[use loc-tite], tighten to flywheel. The best way to remove the original trigger plate screw is to use pliers and twist the plate as you loosen the screw [prevents destroying the screw].

    Hope this helps,
     
  17. go-rebels

    go-rebels Member

    Hi Quenton,

    I'm a little confused now.

    It seems that there are two ways to advance the timing:

    1 - Advance the gear one tooth. Any more and you advance the timing too far (poor low speed performance).
    2 - Keep the gear alignment the same and move the trigger plate on the flywheel counterclockwise until the rear edge covers 1/2 of the original hole.

    Either way you change the timing of the trigger signal relative to the rotational position of the cam an identical amount, right?
     
  18. RdKryton

    RdKryton Active Member

    We are confusing two different things here. Ignition timing is moving the trigger on the flywheel. That is only changing the time when the spark fires. Cam timing is advancing the cam one tooth CCW for different valve timing. Changing the cam one or two teeth CCW will not change the ignition timing. By the same token advancing the ignition timing will not change the cam timing. I hope this helps clear this up for you. It can be easy to confuse the two different types of timing.
    Advancing the ignition timing will probably only show a noticeable difference if you engine is highly modified however the cam timing should be done even to a bone stock engine. It will yield the most performance improvement but only one tooth CCW.

    Jim
     
    Last edited: Jan 9, 2009
  19. go-rebels

    go-rebels Member

    Ah, yes... my bad!

    1) Moving the trigger changes the spark timing, that is when the spark fires relative to the position of the piston. This is the "timing" that we changed on the old cars when we fiddled with a timing light.
    2) Moving the gear changes the timing of the valves relative to the postion of the piston. Shade tree mechanics normally never changed this on the older cars.

    RdK, thanks for the clarification!
     
  20. RdKryton

    RdKryton Active Member

    Glad I could help.
    Enjoy the ride. I can't wait for warm weather. It's supposed to snow here tomorrow. Booo

    Jim
     
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