Custom Frame For Thumper Motor

Discussion in 'Motorized Bicycle Welding, Fabrication and Paintin' started by culvercityclassic, Apr 8, 2011.

  1. tommyboy1442

    tommyboy1442 Member

    Joined:
    Nov 25, 2009
    Messages:
    239
    Likes Received:
    0
    who said anything about 4 stroke?
     
  2. culvercityclassic

    culvercityclassic Well-Known Member

    Joined:
    Sep 27, 2009
    Messages:
    3,071
    Likes Received:
    47
    I completed the chain tensioner that was needed on this bike. Purchased the sprocket from "Pirate Cycles" and must say the quality is top notch and well worth the price.

    I played with a few options and this worked out the best; it’s fully adjustable and works very well...hopefully no more chain issues.

    I guess I can say the bike is done...well until I get the alky motor done...JK
     

    Attached Files:

  3. scotto-

    scotto- Custom 4-Stroke Bike Builder

    Joined:
    Jun 3, 2010
    Messages:
    6,527
    Likes Received:
    5
    That's a beauty, it go's well with the brake anchor arm and micro adjustable!

    dnut
     
  4. bairdco

    bairdco a guy who makes cool bikes

    Joined:
    Aug 18, 2009
    Messages:
    6,333
    Likes Received:
    19
    that's a great lookin' tensioner. finally, something that works...
     
  5. silverbear

    silverbear The Boy Who Never Grew Up

    Joined:
    Jul 9, 2009
    Messages:
    8,186
    Likes Received:
    8
    Pretty slick, Bud...
    SB
     
  6. silverbear

    silverbear The Boy Who Never Grew Up

    Joined:
    Jul 9, 2009
    Messages:
    8,186
    Likes Received:
    8
    Pretty slick, Bud...
    SB
     
  7. culvercityclassic

    culvercityclassic Well-Known Member

    Joined:
    Sep 27, 2009
    Messages:
    3,071
    Likes Received:
    47
    I got The bike back running tonight and posted a video of how it sounds. Took it out in the neighbor-hood and almost looped it and when the front end came down it bottomed out real hard. I need to add some more dampening spacers back in the fork. The chain tensioner works great so far...

    This is a fun bike but i need to get more safety gear to wear for sure.


    P9070001 02 - YouTube
     
  8. scotto-

    scotto- Custom 4-Stroke Bike Builder

    Joined:
    Jun 3, 2010
    Messages:
    6,527
    Likes Received:
    5
    You must have put the big sprocket on eh? Welded the broken brake arm on mine today.....time to dial in the jetting now. So much fun ripping thru the neighborhood :D

    dnut
     
  9. silverbear

    silverbear The Boy Who Never Grew Up

    Joined:
    Jul 9, 2009
    Messages:
    8,186
    Likes Received:
    8
    You've done a beautiful job on that bike. What a machine! Nice center stand, too. No tip overs with that one.
    SB
     
  10. msrfan

    msrfan Active Member

    Joined:
    Sep 17, 2010
    Messages:
    1,714
    Likes Received:
    8
    Hey ccc, I was researching the comet specs and it's supposed to operate at 3100 rpm max. My motor revs up to 6400. Do you think it's a high speed balance limitation? I don't want to break my crank off and take my leg with it. Appreciate your input.
     
  11. culvercityclassic

    culvercityclassic Well-Known Member

    Joined:
    Sep 27, 2009
    Messages:
    3,071
    Likes Received:
    47
    Hey thanks for telling me that now...I rev it till it red lines at 9500... JK
    I am not sure what my bike revs to but I just made some changes and it really moves.

    What I do notice is the bike really shakes from the cvt at hi speed...but it also will Cruz very well. It's a fine line and the older I get I really don't feel like getting hurt.

    Tell me what you noticed when you rode your bike
     
  12. msrfan

    msrfan Active Member

    Joined:
    Sep 17, 2010
    Messages:
    1,714
    Likes Received:
    8
    Okay, thanks for the info. When I get mine going, I'll rev the motor without the belt and check the vibes.
     
  13. Gbrebes

    Gbrebes Member

    Joined:
    Jul 16, 2010
    Messages:
    577
    Likes Received:
    20
    I just happened upon this thread, and I plan on switching out my centrifugal clutch with a comet clutch, so I got worried about this max rpm thing. I researched it a little on mini bike and go kart forums and re-read the specs and I believe it is stating that the range for the clutch engaging is 1200 min. to 3100 max. I do not believe that is the max rpm the clutch can handle.

    Please correct me if I am wrong.

    Gilbert
     
  14. culvercityclassic

    culvercityclassic Well-Known Member

    Joined:
    Sep 27, 2009
    Messages:
    3,071
    Likes Received:
    47
    Gilbert...I tried to find that information, can you post where you found it? The drive I have is a GTC brand just so you know; it works on the same principle as a comet.

    The bike runs good and I did a 35 mile ride today with no issues. The only thing I see is a new belt in the near future.
     
    #174 culvercityclassic, Sep 12, 2011
    Last edited: Sep 12, 2011
  15. Gbrebes

    Gbrebes Member

    Joined:
    Jul 16, 2010
    Messages:
    577
    Likes Received:
    20
    I found it here. In the first blue box under the picture of the drive pulley it states "engagement range: 1200 rpm - 3100 rpm. It also states that you can adjust the spring for driving in more hilly terrain.
     
  16. msrfan

    msrfan Active Member

    Joined:
    Sep 17, 2010
    Messages:
    1,714
    Likes Received:
    8
    Thanks for that info, Gbrebes, it gives me hope. I'll keep researching.
     
  17. curtisfox

    curtisfox Well-Known Member

    Joined:
    Dec 29, 2008
    Messages:
    3,999
    Likes Received:
    30
    Me thinks after it reaches the full 3100 and is full out it won't make any moves or changing no mater how fast you rev it. The only thing is the balance or vibration.
    Most of them are stamped and mass produced so could be out of balance.
    Might need to take it apart and weigh each piece or whatever it takes to balance it.....Curt
     
  18. scotto-

    scotto- Custom 4-Stroke Bike Builder

    Joined:
    Jun 3, 2010
    Messages:
    6,527
    Likes Received:
    5
    Mine engages at 2,200rpm and I'm keeping the idle at around 1,800rpm. It only takes a blip of the throttle to launch this rocket. It's a very fine line.

    On a side note, I just got pulled over by the cops (a few minutes ago) and they thought I have a very "interesting contraption". I agreed and told them it is my race bike and I'm out testing it. They told me to put lights on it as it is dark out now (after running my license) and I replied no problem, had them in my backpack. Ya gotta love that!dance1 one block away from home, after a 10mile tour!

    dnut
     
    #178 scotto-, Sep 12, 2011
    Last edited: Sep 13, 2011
  19. culvercityclassic

    culvercityclassic Well-Known Member

    Joined:
    Sep 27, 2009
    Messages:
    3,071
    Likes Received:
    47
    I really don't think we need to worry about the CVT; for one thing they have been in use for some time. I have not seen any cautions or warnings about over-revving or self destruction. It's an all around great design with a proven history.

    So I am going to race it, lug it and Cruz it till death do us part…and love it…

    Pictures: Playa Del Rey Elks Car Show Saturday
     

    Attached Files:

  20. culvercityclassic

    culvercityclassic Well-Known Member

    Joined:
    Sep 27, 2009
    Messages:
    3,071
    Likes Received:
    47
    The quest for the perfect race bike and daily rider...the latest to come out of the SPORTSMAN garage...this hub and adapter with a split sprocket for easy swaps with-out the removal of the wheel. Such a smart design...The request from Pat: see if you can break it...lol Thanks Pat....for the hub...it sure is a beauty

    Lucky for me I have an area that I have setup for hard runs and a practice track a mile from my house..The old Hughes Air Craft area...
     

    Attached Files:

Share This Page