The *BEST* Solution for "THE" tensioner/pulley

Discussion in 'Motorized Bicycle General Discussion' started by longhorn6, Nov 1, 2009.

  1. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    The chain guide or tensioner allows for fine adjustment once set up properly, while half links and 1" of drop out adjustment can't.

    That's the reason for the tensioner, cheap as it may seem.
     
  2. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    I've done that too!! it works very well! Look at the 'Paul Frank' bike on my website...
     
  3. Nashville Kat

    Nashville Kat Active Member

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    Yes- tensioner on the pedal side-

    THEY CALL IT A "DERAILLEUR"!!!!!!!

    This takes care of the tensioning between the two chains at least- And you have a pedaling choice- at generally no more weight than the standard tensioner- which in fact is HEAVIER than a lot of derailleurs. (of course the extra cogs add some weight too)

    Like others have said here, you still may have some allignment problems- this can usually be anticipated by simply sighting before installing- is the back sprocket behind the motor sprocket? remember axle spacing is possible too.

    And some chain rear dropouts may unluckily not allow the correct motor chain length like Veniceboy has said- but probably will more than not.

    Mountain bikes may make good builds, but so many have VERTICLE DROP-OUTS (like criterium racing bikes). Verticle drop-outs leave no margin for chain adjustments.But the best bikes for build, at least as far as chain tensioning, are ones with long horizontal dropouts- some may even have screw adjustment, like Campagnolo road dropouts.
     
  4. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    A derailleur doesn't work well with a coaster brake tho...
     
  5. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    I've found that the best way to get rid of the tensioner is to use a combination of 1/2 links (& or) different size sprockets on the pedaling side chain to get both chains the same tension.
    The 1/2 links don't work very well on the engine side!!
     
  6. Nashville Kat

    Nashville Kat Active Member

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    No- a derailleur doesn't work with a coaster brake, so I was talking more about when you may be deciding what bike to build-

    Coaster brakes are convenient- but handbrakes work well- especially with a dual brake handle, or things are cluttered otherwise-

    I've put an alloy 27 x 1 1/4 rim on my cruiser- which is lighter and really rolls better than the 26 x 1.75. But the best part is that I was able to put a Campagnolo side pull brake on- and it really is a great brake! Much better than the original cantilever.
    I thought about a bigger wheel for the back, but am gonna leave the 26" on, just to not have to mess with it. I'd have to get another caliper brake with a fairly long reach too, because the micargi frame support is drilled through at an upward angle.

    Anyway it sorta looks cool like a Harley with a bigger skinny wheel on the front. and rolls better too.
     
  7. Dan

    Dan Staff
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    I kinda cheat on the half link thing. If it needs a half link, I just tip the engine either way. Another shortcut that I certainly wouldn't advise, but use with success.

    Not sure I have ever had a single carb bowl that was dead flat and plumb.
     
  8. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    I usually mount the engine first with the rear mount square & straight into the seatpost tube. I just get the engine mounted where ever it sits best & then deal with the chain issues (if any?) after that.
     
  9. xlite

    xlite New Member

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    2door, Kevlarr, and Venice seem to have experience with both approaches and have a grip. Most of the other guys are just talking through their hat or religious fervor (what else is new).

    If you have chosen a good platform it's easy to do without a tensioner and you'll be rewarded with higher reliability and performance. If you went for looks instead of function and ended up with an oddball "problem" bike then you must live with the consequences and the tensioner may be required.

    And I can't imagine what these guys who say "you'll have to cut your chain" are talking about. Every install required removing links tensioner or not. Often you wonder if some of the guys have even SEEN a HT let alone installed one.
     
  10. sportscarpat

    sportscarpat Bonneville Bomber the Salt Flat record breaker

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    New around here and my first attempt at a motor bike and my solution to the idler sprocket. I will try to post a picture. Here goes. Well, the attachment worked. I used a #41 Diamond brand chain, an 18 tooth idler sprocket with bearing insert, tig welded a small laser cut tab to the bottom of my frame. The weld on tab is slotted to corectly adjust chain tension. Works great and have had absolutely zero problems.
     

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  11. 2door

    2door Moderator
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    Very Very nice. Its less welding and more eye pleasing than mine. Good work my man. Thanks for sharing.
    If I'm seeing this correctly, (master link just leaving rear sprocket?) I'm not being picky here but you should really turn the clip on your master link around. The closed end should enter the engine sprocket first. The way you have it, it can get kicked off by interference with the sprocket/ clutch actuator case. Just an observation that might prevent a chain loss. If I'm seeing it right.
    Tom
     
    #31 2door, Nov 3, 2009
    Last edited: Nov 3, 2009
  12. Prasinos

    Prasinos New Member

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    Having no pensioner would be nice no doubt but don't forget that no matter how tight your chain is it still may need a tensioner. Ive built 10 bikes now and some have output sprockets that are almost a half inch out of line with the rear sprocket and the tensioner fixes this. It would be a real pain in the butt to fix this problem without it. For the record, i like having a spring tensioner but i have no problem with the stock one. Besides having to bend some to get them to line up there are little to no problems once set up.
     
  13. sportscarpat

    sportscarpat Bonneville Bomber the Salt Flat record breaker

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    No tensioner would be nice and I could have done that, but what I found in my application is that the chain would rub the frame chain stay. By lifting the chain in this area it allows the chain to clear the frame. Sometimes the bike tells you what it needs.
     
  14. Dan

    Dan Staff
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    Very cool! Really like the looks and function. Purty work Sport.
     
  15. Nashville Kat

    Nashville Kat Active Member

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    RELIGIOUS FERVOR?!!!
    You want some religious fervor? I'll give you some religious fervor!

    Question: Why are Mormons buried EIGHT feet underground?
    Answer: The two extra feet is for the bicycle.

    Prasinos says above: "Having no pensioner would be nice..." Must be a Republican. Ya
     
    #35 Nashville Kat, Nov 3, 2009
    Last edited: Nov 3, 2009
  16. Dan

    Dan Staff
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    Dang Tom! With glasses on and magnifying glass, (no kidding) still am not sure but think your right. Great catch.

    Chain coming apart is a really bad thing at speed. I really can't see if it is reversed though Sportcarpat.

    Tom makes fun of me for remembering it as a lil rocket propelling the chain. I remember the ball bearing chain cages on the bottom bracket by; protect your balls, face 'em inward" (LOL, I are slow and actually need these weird lil ways to remember stuff)
     
  17. BarelyAWake

    BarelyAWake New Member

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    I bet he's got a 5' monitor... geez

    Good eye Tom lol
     
  18. bandito

    bandito New Member

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    With IE8 you can magnify up to 400x by 1 click on the bottom of the screen.
     
  19. Dan

    Dan Staff
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    my best bud is blind and uses "zoomtext" doubt he would have cought that. Amazing Tom
     
  20. 2door

    2door Moderator
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    Photo Shop...I can ANYTHING with Photo Shop. Actually I saw his master link on my old 80s vintage monitor at work. I downloaded that pic to PS and enlarged, enhanced it and used a shapening filter. It looks like its backwards but I'm not absolutely positive. I'm still waiting for a reply from him to confirm.
    Tom
     

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