Is it realistic/sensible to upgrade number of rear gears

UEX

UEX

UEX

Associate
Joined
4 May 2007
Posts
234
Sorry for non techie language. Long story short I bought a hybrid bike from halfords nothing mega was like 300 quid. Turns out the years in the gym have left me with good leg power so I'm finding the gearing a bit limiting. Uphill obvs is no issue but on anything approaching flat or downhill I have nowhere near enough gears to bother pedalling which I find boring. It's a 7 gear rear cassette I believe with 3 on the pedals.

Is it worth upgrading these or do I basically consider a new bike already? If I do upgrade how much of a polava is it? I've got tons of tools I regularly work on cars etc.

Any advice appreciated
 
If you don't have enough speed on flats it's typically not a rear cassette issue and is the gearing on the chainring (the gears where the peddles are). Count how many teeth you have at the back on the smallest cog, if it's 11, then you'll have to change the chainring instead and tbh, I'd rather buy a new bike at that point.
 
I see so I guess 11 is like the least the rear can have? If I was to buy a new bike how could I check ahead of time that things would be better?
 
11 is the norm for a road bike.

Check the lowest amount of teeth on the cassette and the largest amount of teeth on the chainring. So somewhere on the page it'll give you the cassette range which looks like "11-32" for example, the smallest being the number you pay attention to for speed.

For the chainring you look at the largest number, 52 in a "52-36" chainring.

Count how many teeth the largest chainring on your bike has and if you buy a new bike, make sure it's larger than what you have now.
 
UEX said:
I see so I guess 11 is like the least the rear can have? If I was to buy a new bike how could I check ahead of time that things would be better?
Click to expand...

Can you take a photo of the bike or do you know what group set (gears etc it has). Maybe send a link of it online.

If you're spinning out on the flats then you might be able to ust add a larger front chain ring.
 
The 48 tooth chain ring is your problem, if you had a 50 or 52 then that should help along with a 14 rear, although a 48/14 should have to you spinning at 110rpm @ 30mph. A comfortable 90rpm should be close to 25mph on the flat which is quite reasonable.

If you feel you want to go faster then get a road bike for example the same 90rpm cadence on a 52/11 would mean you would be going nearly 34mph.
 
Last edited:
Bear said:
The 48 tooth chain ring is your problem, if you had a 50 or 52 then that should help along with a 14 rear, although a 48/14 should have to you spinning at 110rpm @ 30mph. A comfortable 90rpm should be close to 25mph on the flat which is quite reasonable.

If you feel you want to go faster then get a road bike for example the same 90rpm cadence on a 52/11 would mean you would be going nearly 34mph.
Click to expand...

So is it realistic to buy a 50 or 52 and replace my 48? Long term I'd prob buy a road bike but I like to bike with the kids up and down gravel and dirt but without being on an mtb so the hybrid kinda suits me
 
UEX said:
So is it realistic to buy a 50 or 52 and replace my 48? Long term I'd prob buy a road bike but I like to bike with the kids up and down gravel and dirt but without being on an mtb so the hybrid kinda suits me
Click to expand...

@Jonny ///M is probably the best guy to speak to as he works in a bike shop but it looks like you need a square taper chainset so heres a 50 tooth https://www.richmondcycles.co.uk/pr...e-chainset-7-8-speed-50-39-30t-170-mm/option/ and another https://www.tredz.co.uk/.Shimano-FC-A073-Square-Taper-Triple-Chainset-7-8-Speed_108852.htm

Running the numbers again, what you gain isnt really worth it and as said before cruising on the flats at 25mph isnt bad at all
 
UEX said:
So is it realistic to buy a 50 or 52 and replace my 48? Long term I'd prob buy a road bike but I like to bike with the kids up and down gravel and dirt but without being on an mtb so the hybrid kinda suits me
Click to expand...

Not really, on cheaper crank sets, the chain rings are rivited together so you's have to replace the whole thing.



I wonder how many teeth the smallest cog at the back has... 14 sounds very big, according to the spec in the link:
Cassette/Freewheel
Shimano TZ500, 7 speed, 14-28t
Click to expand...

Check with soomeone who knows but this should probably fit (11-28 Teeth) and is pretty cheap - will give you higher gearing with minimal fuss:
https://www.amazon.co.uk/Shimano-Acera-HG41-Speed-Cassette/dp/B007QTTYE6/ref=sr_1_4?crid=FTU9QZ7WV4U9&dchild=1&keywords=7+speed+cassette&qid=1618313765&s=sports&sprefix=7+speed,sports,174&sr=1-4

The only downside is there will be bigger jumps in effort between gears as its still only 7 speed, but it doesn's sound like that would be an issue for you.
 
Last edited:
That 14-28 is a freewheel so the best way to increase speed would be to buy a new rear wheel with a freehub body to mount a cassette onto. The 11-28 would for the wheel and give you more top end speed.

Not worth changing front rings to 50/52 as the front derailleur won't like that as it's never been designed for that.

https://www.tredz.co.uk/.Wilkinson-700c-Single-Wall-QR-Cassette-Hybrid-Rear-Wheel_17134.htm

https://www.halfords.com/cycling/bike-parts/bike-wheels/rear-700c-bike-wheel-in-black-244124.html

Those would work if it has v brakes. Discs brakes would need a different one but I'm heading out on the bike so will look later.
 
Jonny ///M said:
That 14-28 is a freewheel so the best way to increase speed would be to buy a new rear wheel with a freehub body to mount a cassette onto. The 11-28 would for the wheel and give you more top end speed.

Not worth changing front rings to 50/52 as the front derailleur won't like that as it's never been designed for that.

https://www.tredz.co.uk/.Wilkinson-700c-Single-Wall-QR-Cassette-Hybrid-Rear-Wheel_17134.htm

https://www.halfords.com/cycling/bike-parts/bike-wheels/rear-700c-bike-wheel-in-black-244124.html

Those would work if it has v brakes. Discs brakes would need a different one but I'm heading out on the bike so will look later.
Click to expand...

Surely He could just buy a cheap 7 speed casette with a 11 tooth high gear? if it's a shimano style free hub. The rear mech would only stretch too much if if he was going 'big' in the opposite direction.

He doenst need a whole new rear wheel, just a new casette, and retune the gears if nessesary.
 
Last edited:
mattyfez said:
Surely He could just buy a cheap 7 speed casette with a 11 tooth high gear? if it's a shimano style free hub. The rear mech would only stretch too much if if he was going 'big' in the opposite direction.

He doenst need a whole new rear wheel, just a new casette, and retune the gears if nessesary.
Click to expand...
That’s what he’s saying, it hasn’t got a normal freehub body but uses a freewheel instead so can’t put a cassette on there.
 
Pretty much.

Multi freewheels only go down to 14t as all the freehub gubbins is inside it and a tool has to fit in to remove it.

A freehub body style wheel has the gubbins inside that and allows an 11t sprocket to sit on the end.

That's why new freehub bodies are needed for 10t cassettes, the cog is smaller than your standard cassette locking used on 11t cogs.

https://www.parktool.com/blog/repair-help/determining-cassette-freewheel-type
 
You must log in or register to reply here.
Back
Top Bottom