Frame rear not wide enough for sprocket

Discussion in 'Frame Mounted Engines' started by impression, May 10, 2009.

  1. impression

    impression Member

  2. bamabikeguy

    bamabikeguy Active Member

    Have you got an estimate of how much clearance you need?

    Is the problem on the upper or lower or both rear stays?
  3. spad4me

    spad4me Member

    It appears to be aluminum DO NOT bend the stays.
    What is a snake stay ?

    You may need to use a shift kit ( to use the drive chain on the right side of the bike) , or get another bike to motorize.
  4. impression

    impression Member

    it's both and i would need to probably get about an inch more room in width so the chain would run nicely.
  5. bamabikeguy

    bamabikeguy Active Member

    AN INCH? Wow.....

    50% of the bikes I build require a small crimp in (usually) one of the stays, but I'm talking about making maybe 1/4"-3/8" inches deep dent. Then I add an extra washer or two, to that side of the axle, to give another fraction of clearance.

    I noticed that it had, standard equipment, a Weimann wheel, so I was thinking you were barely grazing the stay.

    I once "spread" the clearance wider, on a 24" bike, with a threaded rod as an axle substitute, to hold that part of the frame steady, then a car jack to push both sides out a bit. It worked, bike is still on the road years later.

    TIP- can you edit your title to say "Apollo Frame not wide enough for sprocket" That way another Apollo owner might see it and have the perfect solution....
    Last edited: May 10, 2009
  6. impression

    impression Member

    i think i'm going to wait for my shift kit to arrive :S

    kinda nervous about putting it all together, don't want to screw it up. as it cost more than the engine....

    that and the waiting for it to arrive is killing me :p
  7. bamabikeguy

    bamabikeguy Active Member

    Before you beef up the tire/tubes to your liking, just work with the wheel and sprocket first, without the tire and tube weight to contend with.

    It is so much less of a hassle, to check those clearances, without the tire getting in the way.
  8. cpuaid

    cpuaid Member

    maybe going down to a smaller sprocket would be easier than modifying the stay. a 36T is significantly smaller in diameter than a 44T thus giving you that 1" clearance you required.
  9. bamabikeguy

    bamabikeguy Active Member

    The fat tire cruisers, the ones with the 2.25 tires as standard equipment, from those $150 Schwinn Jaguars, to the Sun Cruisers and the $500 Treks, would be "wide" in back.

    Problems occur when you try to convert the bikes that originally came with 1.5"-1.75" tires, even some of the Comfort types with the 2.0" tires are a little tight.

    Bikes have a warning label nowadays, "Don't put a motor on this bike", and on some models, that is "fact" just because of the frame clearances.
  10. HI,

    A Top Hat Sprocket Adapter may help your problem but may require minor spacing with washers etc...each install is a little different.

    Basically the sprocket needs to be moved inward some.

    A less elegant approach I have seen done is simply moving the wheel over by adjusting the cones...of course that may cause you to lose a gear or two on the derailleur side and you'll have to space the rotor out too.

  11. Junster

    Junster Member

    If you have a shift kit coming anyway don't change anything. Go for a ride and get use to your new bike. Come home and drool on your engine. Then get on here and keep reading. Good things come to those who wait. Sry I hated the wait too. Maybe use this time to upgrade your motor studs etc.