Why is the chain tension so loose? >1950 Schwinn Whizzer<

[Real Steel]

I'm setting up the rear wheel on my 1950 Schwinn Whizzer. Its like adjusting four things at the same time! No matter what, the original chain ends up looser than expected.

I can't tighten the chain any further because the drive belt (AX-62) is already taught.
I tried one size longer belt (AX-63) but it makes the chain too tight.
If I removed one link from my skiptooth chain it would be too tight.

Right now with the AX-62 belt the chain seems very loose and the rear axle sits as far forward on the dropouts as I'm comfortable with.

I wish Whizzer had designed their system with an adjustable idler pulley for the belt! But they didn't, and this bike will stay all stock.

Any ideas? Do chains stretch with years of use? Am I missing something here? Am I over-thinking this?

 

[THE STIG]

both belts have to the right sizes . if front belt is to short, the clutch is closer to engine then the rear is off

profile pic ??? engine looks high also

 

[Real Steel]

both belts have to the right sizes . if front belt is to short, the clutch is closer to engine then the rear is off

profile pic ??? engine looks high also

Profile and belt photos:

 

[THE STIG]

i use AX26 belt, whatever that crosses to gates. the center of crank bolt - center clutch bolt is 8" engaged

 

[Real Steel]

i use AX26 belt, whatever that crosses to gates. the center of crank bolt - center clutch bolt is 8" engaged

Verified. I get 8".

 

[THE STIG]

my rear belt is ax62........chain issue???

 

[Real Steel]

my rear belt is ax62........chain issue???

Is there such a thing as 'chain stretch'? I'm pretty sure this is the original chain.

 

[THE STIG]

Is there such a thing as 'chain stretch'? I'm pretty sure this is the original chain.

absolutely

 

[Real Steel]

absolutely

Hmm, maybe that's it. I would guess the chain would need to be shorter by about 3/8 inch. Could it have stretched that much?

 

[THE STIG]

lay chain flat and compress it , then put it apart... theres a spec (i don't know it) see how much longer it gets