Dummy need help with transmission

[WhiteEagle197]

The OP wants to know about Drive trains and how to achieve a better top end yes or no ?

White Eagle, to explain a little more. In your situation ( as I understand it, flatish roads ?) The difference between a 48 chainring and a 52 is going to be just over 1 tooth on the rear cassette, a 50 to a 52 will be under that. As Im sure you can see the bearing of the large chain ring on the front has little effect on top speed unless you are making huge steps. To drive a 52/11 on the flat you will have to be very fit and thats on the drops on a road bike. Descending hills is a different story, but not much. To the cassette, think of your drivetrain has having 2 gearboxes the large and small chainrings. The cassette is the ratios contained within that gearbox. A wide spread say a 11/27 (you can go higher than 27 but this would bring in added complications) will give you a greater range but the steps between gears will also be greater. A narrower spread will give you smoother gear changes and better acceleration for example an 11/23.

Chain ring choice becomes much more important when climbing.

jim55 very imformative but Im sure your comments reflect more on you than they do me

Thank you. I think I will go for a 48/13 or a 48/11 maybe.
Also, I decided to keep my existing bicycle as well (I wouldn't be able to sell it for more than perhaps 50 quid...). If I have the present 42 replaced with a 48 will the bearing be okay with that? I guess there is a bigger force then, and not sure the construction is strong enough for that? Or maybe I should just leave the present bicycle alone...

 

[lukesdad]

I think you may struggle to get the 48 working sweetly on your current set up on the old bike. On the new one, 48/13 may be a little on the small side.My opinion remembering I don t know you, or how you ride but from your brief description, would be to go for a 50/34 front and an 11/25 rear.
you can t go far wrong with that.

 

[WhiteEagle197]

I think you may struggle to get the 48 working sweetly on your current set up on the old bike. On the new one, 48/13 may be a little on the small side.My opinion remembering I don t know you, or how you ride but from your brief description, would be to go for a 50/34 front and an 11/25 rear.
you can t go far wrong with that.

Thank you!

 

[mickle]

I think you may struggle to get the 48 working sweetly on your current set up on the old bike. On the new one, 48/13 may be a little on the small side.My opinion remembering I don t know you, or how you ride but from your brief description, would be to go for a 50/34 front and an 11/25 rear.
you can t go far wrong with that.

Thank you!

Don't thank him, he's trying to destroy your knees.

 

[lukesdad]

Don't thank him, he's trying to destroy your knees.

Ah but thats why we have gears mickle, we ve moved on a bit since your day

 

[lulubel]

A smallest gear of 34x25 should be fine for most situations.

I very rarely use the granny ring on my triple, so the smallest gear I generally use is 42x25. I can go down to 30x25 by using the granny ring, but that only gets used if I'm riding up mountains (or if my legs are knackered from riding up mountains the day before).

 

[GetAGrip]

Learn to spin, it's easily the easiest and the cheapest fix. And it's also the best solution in the long term for you and for your bike.

Here's one I wrote earlier:

" And finally, if there is one piece of advice that you take away from here I hope it's this;
Gear one is low. Try to always be in a gear that feels too low/ easy/ spinny/ soft.
Three rather than four. Four rather than five.
Pushing high/ hard gears puts unnecessary strain on your joints and on the transmission of your bike. Pushing hard on the pedals promotes muscle bulk so if you want muscley legs go ahead and push a high gear.

Spinning fast in a low gear promotes excellent cardiovascular health, reduces strain on your joints and on your bike, allows you to accelerate quicker and you get quicker gear changes. But the bottom line really is a bottom line, spinning gives you a lovely well defined arse and lean legs. What more could you possibly ask for? "

More here.......[/quote

Sorry WhitEagle197 for hijacking your thread! But I just need say -
Thank you, Thank you, Thank you!! You've all helped me make a decision as to which bike I get (very very soon if I have my way ) next.
I narrowed it down to the Giant Dash, but was torn between 1 = compact 20 gears or 2 = triple 27 gears.
Reading this thread has convinced me that with a dodgy knee, it would be soooo wrong for me to discard my 'granny' ring. I was trying to kid myself I could work hard to get fit enough not to need a little ring.
I have now decided on the Dash 2 and will be proud of my 'granny' ring. At least she will enable me to go ANYWHERE and EVERYWHERE I so desire. Well in theory anyway . A special thanks to Mickle, who when he wrote his article, it seems he wrote it just for little 'ol me

 

[RecordAceFromNew]

The Kenda tyre fitted to my mountingbike is precisely 26" in diameter.
So ner.

Presumably this

is your mountingbike? Are you sure they are 26" wheels?

 

[WhiteEagle197]

Don't thank him, he's trying to destroy your knees.

What do you mean?

 

[WhiteEagle197]

Oh, I see. Well, I would like to go faster :-)

 

[mickle]

Oh, I see. Well, I would like to go faster :-)

Then ignore all the advice about fitting a larger chain ring or smaller sprocket and learn to pedal faster.

 

[WhiteEagle197]

Then ignore all the advice about fitting a larger chain ring or smaller sprocket and learn to pedal faster.

I don't want anything extreme. On my present bicycle I have 42 and 13 - that is simply just not fast enough on plain road. I feel if I had just one more longer speed (a 48 or perhaps a 11) then it would be just right.