Gears and Brakes

[Riverman]

Cheers.

I guess the bad news is the effect such riding for so many years has had on my body must be bad.

But the good news is I have learned a lot today, and better late than never.

 

[marinyork]

It won't have had any bad effect on your body unless you're having knee problems? It just means you've not been getting much out of cycling in one respect. I'd do some calculations, small changes in the gear ratio can make fairly large ones in speed, you may not be spinning as badly as you think.

 

[garrilla]

Frame size

A quick question about this. I'm 5 foot 8 inches tall and the frame is 18", I was told in the shop that's about right although I feel abit constrained.

When you say constrained, do you mean like this chap?

18" converts to roughly 45cm. That would seem small for someone of 5'8"

I'm having great difficulty imagining you on this tiny bike, spinning like there's no tomorrow, but getting nowhere fast because the brakes are on.

And you say you're not very fit?

 

[RedBike]

18" is normally about right for a mountain bike for someone whos 5'8" and your bike does have a MTBs geometry.

For road use there's it could well feel like you're sat a bit too upright though.

 

[Ant]

When you say constrained, do you mean like this chap?

18" converts to roughly 45cm. That would seem small for someone of 5'8"

I'm having great difficulty imagining you on this tiny bike, spinning like there's no tomorrow, but getting nowhere fast because the brakes are on.

And you say you're not very fit?

Bike sizes seem to be all over the place these days. 18'' on a compact MTB frame is a lot bigger than you'd think. My first thought is that it should be the right size for someone 5'8''

 

[briank]

Cadence?
The hundred and ten revolutions per minute mentioned by RedBike is not outrageous by any means - at least not for sprinters - but it's not sustainable for most of us. 85- 90 rpm is what most experienced and proficient cyclists do: Joe C*nt on a bike probably turns the pedals at 50 rpm.
I think you need to use a watch and count how many times you turn the pedals in a minute - under different circumstances - before you can get much useful advice on this.

 

[Riverman]

No problems with my knees as far as I can tell.

Cadence?
The hundred and ten revolutions per minute mentioned by RedBike is not outrageous by any means - at least not for sprinters - but it's not sustainable for most of us. 85- 90 rpm is what most experienced and proficient cyclists do: Joe C*nt on a bike probably turns the pedals at 50 rpm.

as the forum title suggest I am just a beginner.

You're spot on though. Does anyone else think there wouldn't be much point getting a cycle computer with cadence?

On a final note I do love the aspect of cycling this will erode. I mean there's no point overexerting yourself by keeping in a high gear but sometimes it feels abit like you're down the gym lifting weights. I mean it bloody hurts sometimes and tends to activate your vocal chords but gives a real feeling of satisfaction akin to getting to the summit of a long steep hill.

 

[RedBike]

You're spot on though. Does anyone else think there wouldn't be much point getting a cycle computer with cadence?

Not really. .
If you're not racing / training then it doesn't really matter exactly what your cadense is. All you need is a rough idea now and then.

You can achieve this by counting how many times you push down the right hand pedal (not both) in a minute (or 30seconds and doubling it). At various times in the ride when you feel you need a higher gear.

The 110rpm I picked in my earlier example was suppost to be a realistic maximum. At which point higher gears would be a very good idea. You'll be pleased to hear you don't actually need to pedal that quickly all the time. Anything over about 70 is fine.
(btw, 70rpm still gives you a speed of 20mph! )

 

[RedBike]

nearly forgot.
The cateye astrale 8 is a highly recommended computer with cadence. Normally just under £25.

 

[Riverman]

Went out for a few short rides recently and two things have come out of this.

I'm finding I can accelerate quite quickly by spinning and changing gears quickly, I'm amazed this didn't occur to me earlier

I think I'm going around 70/80 rpm on the flat in the highest gear, it might be abit faster but I can't tell as I still haven't fitted the speedo. I might be completely wrong though! I feel comfortable with this as long as things don't incline too much.

To be honest I don't think I like spinning, it's too much damn hard work lol. I find that if I spin in a lower gear, I want to change back up. I must be spinning too fast though as I still have this urge to shift back up to go faster, I feel like I have to spin my legs like a washing machine cyclinder to pick up speed.

I don't think I'm going that fast really. I haven't done a ride yet over 15 miles, so we will see whether I can keep this high gear thing up.

One place where the spinning is definitey helping is on some hills.

 

[RedBike]

I think I'm going around 70/80 rpm on the flat in the highest gear, it might be abit faster but I can't tell as I still haven't fitted the speedo. I might be completely wrong though! I feel comfortable with this as long as things don't incline too much.

Something still doesn't add up there. At 70/80rpm in top gear you should be doing 20-25mph. 20mph is extremely quick. 25mph is quicker than most people can time trial at!
You'd leave most experianced riders on their carbon roadies for dust at that sort of pace!

To be honest I don't think I like spinning, it's too much damn hard work lol. I find that if I spin in a lower gear, I want to change back up. I must be spinning too fast though as I still have this urge to shift back up to go faster, I feel like I have to spin my legs like a washing machine cyclinder to pick up speed.

If you've got used to grinding away then anything else is going to feel strange / wrong. Spinning a lower gear is going to seem harder work to begin with, espeshially as it does cause you to be more out of breath. But once you get used to it you should notice that you're quicker at the tops of hills / the end of the ride. Your legs won't have that heavy feeling.

 

[Arch]

To check you cadence - if you have a watch with a second hand, or a digittal one with a seconds display, try strapping it round your handlebar so that you can easily see when a minute is up, and still count your revs (like a doctor taking a pulse) - just count one everytime your right foot completes a rev. And test on a bit of clear straight road, so that you can watch the watch without risk of running into anyone.

If yu're not feeling any ill effects yet, your may be ok, but things like knees can suddenyl decide they just don't want to take it any more, if you are straining them. Imagine just leaving your car in 3rd all the time - it'd maybe get going, and keep going, but eventually your gearbox would just wear out...

70-80 rpm on the flat is fine - the point of your gears is that you should be able to maintain it, within reason, going up hill as well, that's why you change down. You go slower, but your legs carry on doing more or less the same (well, I always end up grinding a bit on anything too steep or long)

A good cyclist is one of those people who appears to go uphill with little or no more effort than the flat - because they are still spinning, as opposed to grinding. The sort of people who overtake me...

 

[Riverman]

A good cyclist is one of those people who appears to go uphill with little or no more effort than the flat - because they are still spinning, as opposed to grinding. The sort of people who overtake me...

Something makes me feel like I'd have to spin at 110rpm or above to go the same speed uphill as I do on the flat.

I will do what you said if I can find a suitible timing device. My feeling is I'm going a lot slower than I think, but I'm probably going 20mph occaisonally.

 

[MacB]

Riverman, I know this has gone a bit off track, people aren't really having a go just trying to get to reality. A big point to understand, you don't have 21 sequential gears, there's a lot of overlap. To start with it's worth looking at how hard to turn, or the return given, from each of your ring and cog combinations. A quick peek on Sheldon gives a range:-

big ring - from about 34 to 90 inches across the 7 cogs on the cassette
middle ring - 27 to 71 inches
little(granny) ring - 20 to 52 inches

if you compare gears on ease of use you only have 5 gears, out of the inner 14, that are easier to turn than your easiest gear in the big ring. Bearing in mind your easiest gear, in that ring, is 34 inches, you could quite happily get rid of the other front rings. A 7 speed bike, with that range, will give you all the gears you need. what it won't do is allow you to have smaller incremental changes, to allow you to maintain cadence as well.

Using a 48 ring, and 13-34 cassette, would actually be quite a good fast touring setup. Get you up most things(minus heavy baggage) and big enough gear to trundle along at 20mph ish if you've got the legs.

 

[Riverman]

Thanks.

I hope I'm not coming across as arrogant. I'm genuinaly curious to get to the bottom of this. I am not a very fit at all, thus I've always assumed I can't be going very fast, even though some of my posts may have given a different impression.

I've sort of got my head around your post MacBludgen. A 7 speed is an interesting proposition. However I think there are two problems

Ideally I'd want the same range as I have (on the top chain ring) now but with a higher gear, but if I wanted that higher gear on a 7speed, wouldn't it mean my lowest gear was higher than the lowest I have now on my top chain ring?

Even though I don't use the lower rings, there are hills round here where I SHOULD use them (eg the map I posted earlier) so I should probably keep them.