biopace on singlespeed?

[letmetalktomark]

sod it,gonna go bio to see what its like,remember bitd it was a bit strange but hey,so am i lol

That's the spirit

I've always quite like the idea and no problems with my knees either

Also must make me odd too

M

 

[velomaniac]

Oval chainring on a SS can actually give you two gears one slightly lower when you need it.

Oval long point is lined up with cranks so that when the crank is at the top of its stroke, the point when the most power can be transferred from the rider, the gear is highest.

When cranks reach horizontal, lowest amount of power transfer, the gear has dropped slightly due to a decreased diameter which in turns helps to prevent loss of traction.

In short biopace chainrings on a SS off road is a good thing

Least thats the theory :roll:

 

[barry2017]

You're describing oval rings. Biopace is the other way round.
The reason I wouldn't want to do it is because they've got little ramps to make shifting between them easier.

 

[velomaniac]

Biopace chainrings are oval so don't get confused with other oval rings and are aligned with the longitudonal axis in line with the cranks as I describe. Oval chainrings, not biopace, from the road bike world were mounted with the longitudonal axis at right angles to the crank and evidense suggested they were bad for the knees unlike biopace which had involved complex ergonomic and biomechanical studies in their development.
Most non SS specific chainrings also have shifting ramps but as long the chainline and tension are good, unshipping a chain is unlikely

 

[RockyMountainHigh]

Friends don't let friends ride Biopace - IMO.

Ride fixed gear for a while so you're legs are loose and you spin a nice smooth circle.

 

[MJN]

Friends don't let friends ride Biopace - IMO.

Ride fixed gear for a while so you're legs are loose and you spin a nice smooth circle.

I'd go along with this,and so would my nuts(which are likly to have a close relationship with the stem :cry: )+ biopace feels wierd and works wrong,the strange roadie ones are correct but still strange

 

[dekerfintheshed]

I ran s/s Biopace on the HKEK as Chris mentioned earlier. There's no issues with tight spots etc as exactly the same amount of teeth are on the chain regardless of ring position. I rotated mine (i think) one bolt hole a la Chris Bell Egg rings and it did feel a bit more powerful but that's probably psychological

 

[REtrouble]

A little late, but I've just stumbled across this by Sheldon Brown -

Biopace and Fixed Gear

People are often astonished to learn that I ride Biopace chainrings on fixed-gear bikes. They imagine that there will be tremendous changes in chain tension as the chainring rotates. In practice, this is not the case. A 42 tooth chainring will generally engage 21 teeth against 21 chain rollers, regardless of its shape.

There is a slight variation in tension resulting from the varying angle between the two straight runs of chain as the axis of the chainring rotates, but this has not generally been of a sufficient magnitude to cause any problem in practice for me.

 

[kaiser]

Gonna boing this for clarification, so no long words. Is the theory that the largest part of the oval goes in line with the crank arms?

 

[velomaniac]

YES