5 speed freewheel

[Angelfishsolo]

Hi guys. I think that the smallest cog on my Shimano Cadet 5 Speed Freewheel has damaged teeth. I can pick up a new one for around F10 but there seem to be two types a 14-24 or 14-28. Considering this is going on my old MTB and I use the largest cog a lot on hills would I be correct in assuming the 14-28 would be the better option?

 

[sloe]

Get the one that most closely replicates what you've already got.

If there's any room/slack for playing around then yes a bigger number on the back wheel allows you to pedal up steeper gradients.

 

[cadseen]

yes 14-28 would be better for hilly terrains.

 

[Angelfishsolo]

Can I take it that by slack you are referring to chain tension? or is my brain just fried? lol

Get the one that most closely replicates what you've already got.

If there's any room/slack for playing around then yes a bigger number on the back wheel allows you to pedal up steeper gradients.

 

[jimboalee]

Cycle gearing is a strange subject. There are some ‘old wives tales’ which after 80 years still ring true.

Tale 1. Weigh your bike, with all its accessories and luggage, IN POUNDS. Reciprocate this number and multiply it by ONE THOUSAND. That is the gear length IN INCHES you will need to climb a 1 in 10 gradient after already ridden 100 miles.

Example ; 25 lb all up weight. 1/25 = 0.04. 0.04 x 1000 = 40. 40” gear length.


Be careful when you consider installing a bigger sprocket than what was standard. The upper jockey wheel might bounce on the tips of the sprocket teeth because it is pressing up against the freewheel block. I think this is the ‘slack’ that has been mentioned.

 

[sloe]

Example ; 25 lb all up weight. 1/25 = 0.04. 0.04 x 1000 = 40. 40” gear length.

Well that's it all simplified.

Clear ?

 

[Angelfishsolo]

I understand the maths but am curious how one factors in such variables are increase / decrease in body weight from pit stops , the changing luggage weight when supplies are eaten / replenished and of course the constant decrease in weight from tyre and brake wear.

Well that's it all simplified.

Clear ?

 

[Angelfishsolo]

Cheers - That said I have just rechecked the freewheel and it is a 14-28 so it's the largest I can get

Be careful when you consider installing a bigger sprocket than what was standard. The upper jockey wheel might bounce on the tips of the sprocket teeth because it is pressing up against the freewheel block. I think this is the ‘slack’ that has been mentioned.

 

[sloe]

Well when in doubt go large.

And never ever take my advice.

 

[Angelfishsolo]

I used to have a lady friend who said the same thing

Well when in doubt go large.

And never ever take my advice.

 

[jimboalee]

The equation, I admit, is very rough and ready. Just like the riders of yesteryear. Today bikes will propably have a lower ratio than the equation suggests, which makes it easier to ride up the hill.
Not so long ago, on a 39 x 23 fitted to a bike weighing 22.5 lb, Msr Merckx won several TdeF. Nowadays, they need a bike weighing 15lb with 39 x 25 !! Puffs.

 

[jimboalee]

Thinks back….and referring to my charts.
My SWorks has four ratios lower than 59". Its about 100 miles from my house to the Ponderosa Café at the top of the Horseshoe pass, and the road goes to 1 in 8 at its steepest. I used 53" for most of the climb and 48" on the steep bit. I took this as an indication for further training.
The next weekend, I rode a 150km loop and then tried the hill out of Meriden which is an 11%. No problems on 60". Theory is true.

The message here is:- If the equation gives you a gear too high for your ability, get stronger.

 

[sloe]

I used to have a lady friend who said the same thing
Quote:
Originally Posted by sloe View Post
Well when in doubt go large.

And never ever take my advice.

That's just shamelessly bigging yourself up.