jeyboi wrote:

Simpleone wrote:Thanks for the maths, good to see that I was right about the load on the chain also why companies like Shimano make tougher freehubs for 29ers.

So by your reckoning a chain is under more tension in on a 29er than a 26er for any given gear assuming the same force is exerted on the crank?

If the same force is exerted on the pedals (say 50kg) and the gear combination is the same, say 36/20 (not the same gear inch though). Then the chain tension is exactly the same (120kg).
The only thing that changes is the resultant force that the wheel/tyre is creating. In this case it is 15.1kg of force at the contact patch for a 26" vs 13.8kg for the 29er.

Bike nerd? Maybe.

Garth wrote:Bike nerd? Maybe.

Who cares? your replies are based upon real life not internet 'facts'. Which is probably the one thing which has prevented this from becoming 'another' one of 'those' threads

Keep up the good work.

are we talking sram kgs or shimano kgs??

My bad, I should have expressed the forces in Newtons.
Everybody knows that the kg are only valid for what planet I'm on.

So you are an Alien then Garth...........

evilroyslade wrote:So you are an Alien then Garth...........

We prefer the term "freak"

Garth wrote:

jeyboi wrote:

Simpleone wrote:Thanks for the maths, good to see that I was right about the load on the chain also why companies like Shimano make tougher freehubs for 29ers.

So by your reckoning a chain is under more tension in on a 29er than a 26er for any given gear assuming the same force is exerted on the crank?

If the same force is exerted on the pedals (say 50kg) and the gear combination is the same, say 36/20 (not the same gear inch though). Then the chain tension is exactly the same (120kg).
The only thing that changes is the resultant force that the wheel/tyre is creating. In this case it is 15.1kg of force at the contact patch for a 26" vs 13.8kg for the 29er.

Bike nerd? Maybe.

what about for the same Inch then ?

Two bikes with the same gear inch (distance traveled with one crank rev) but different wheel sizes will have the same chain tension as long as the front cogs are the same size.

As the front cog reduces in size for the same gear inch, the chain tension increases.

Garth wrote:Two bikes with the same gear inch (distance traveled with one crank rev) but different wheel sizes will have the same chain tension as long as the front cogs are the same size.

As the front cog reduces in size for the same gear inch, the chain tension increases.

Shouldn't you be out riding your bike?

Meh - I reckon Garth should be running 1:1 - might give everyone else a chance

Yer, but even Garth won't be able to pull that ratio for long

RussS wrote:Meh - I reckon Garth should be running 1:1 - might give everyone else a chance

would 2:2 have the same amount of torques?