Chainset Size..

skooter

I have been doing a bit of research and it seems the standard front on a 10speed is a 36/22 but as I'm not racing just normal riding so I'm looking for a little bit higher gearing?
I would like a 40/26 but not seen one so I have a choice of 40/28 but the 28 small ring is one higher or 38/26 and the 38 ring is one smaller the other way..
So which one is the better do you reckon?

Cheers

cooldad

About the third thread that mentions this, but...

At a relatively mild cadence of 80, the top speed in 36/11 will be about 35kph or 22mph for luddites.

With a 38 ring this increases to 37kph, or 23mph.

With 40, 39kph/24mph.

How fast are you wanting to go?

The Rookie

As you are not racing you want taller gearing to go faster? Confused much?

I regularly log 25mph pedalling on a 32 chainwheel (and have hit nearly 30) how fast do you want to go?

skooter

Cooldad.

I did have a look for this type of question but found nothing, perhaps I looked in the wrong place?
A 38 ring and 37kph would be fine that's better than I thought.
The other good thing is a 26 inner will be far better for me than a 22 inner.

Rookie.. Going faster is for riding on tarmac.

The other thread you guys answered for me on a tripples came to nothing as I have just bought two Trek mtb's for peanuts and they are both doubles but thanks for answering and hence the new question.
PS The two Treks I bought at stupid prices was Superfly 5 and a Ex- Caliber 8..

Happy new year to you both..

The Rookie

So how fast do you think you'll be going that you need something taller than a 36T? Apart from down fairly steep hills you won't be spinning that out, a 38t is such a small benefit it's not both the bother (unless the 36 is dead), a 40t just about worth the bother, 26t grannies are available so just buy them separately.

skooter

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19770505#p19770505]The Rookie[/url] wrote:

So how fast do you think you'll be going that you need something taller than a 36T? Apart from down fairly steep hills you won't be spinning that out, a 38t is such a small benefit it's not both the bother (unless the 36 is dead), a 40t just about worth the bother, 26t grannies are available so just buy them separately.

The Superfly 5 has a Race Face Ride so what is that equal to in Shimano do you know off hand ? and I will look at other different rings..
If I went 42 outer which is 104 what size would be the 28 would it be 64.

Cheers

cooldad

That depends on the BCD of the crankset. You can only fit rings with the same BCD. And number of bolt holes, obviously.

But if you want to fly on the road, you should probably try a road bike.

skooter

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19770548#p19770548]cooldad[/url] wrote:

That depends on the BCD of the crankset. You can only fit rings with the same BCD. And number of bolt holes, obviously.

But if you want to fly on the road, you should probably try a road bike.

I have too many road bike's hence getting a mtb ot two, I just dont want to be hard core on a mtb.. middle of the road you could say.

The Rookie

Crunch the numbers here
http://www.bikecalc.com/speed_at_cadence
Unless you are topping 32mph you don't need a bigger top ring! (110rpm cadence which isn't mega fast).

BigAl

as I have just bought two Trek mtb's for peanuts and they are both doubles but thanks for answering and hence the new question.
PS The two Treks I bought at stupid prices was Superfly 5 and a Ex- Caliber 8..

Happy new year to you both..

Seeing as you already have the bikes why don't you just ride them and see?

Change chain rings (or cassette) to suit if you need more at the top or bottom end

I'd be surprised if 38-11 is too low

The Rookie

If you read his other threads, he doesn't actually have them yet.

BigAl

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19772749#p19772749]The Rookie[/url] wrote:

If you read his other threads, he doesn't actually have them yet.

Not seen his other posts

Then again, the 'wrong' chainring size (by 2T) is hardly a reason not to buy a bike

The Rookie

He's bought it, just not yet got it, and thinking of changing it before even riding it.....

skooter

Morning Guys,
Couple of things - I had a Trek Elite 8.5 3 years ago which I had for a month, but I came off my 450 motocrosser and hurt my neck so I sold it, the gearing was 42/32/26 and for what I did at the time it was good enough and I only used the small ring once or twice. My neck has now improved a little bit so I would like to do some gentler off roading.
If I was buying a bike to ride the really steep climbs on the mountain where I live over here which in Spain are rough gravel with rocks and boulders (and can get up to 30% gradient in 2 mile long stretches) I would indeed want a 22 small or even smaller if they did one, but as I have bought it for the more gentle inclines of the area in Kent where we have a house I'm happy with what I'm doing.

PS.. If I ride round on the bike and use the components I will get peanuts for them but if I take the components of first I can sell them and I will get a much better price as new but not use?
Paul.

skooter

Something else that has just cropped up.

We land at Gatwick with the bike so I decided to get the XT crankset M785 40/28 (BB included) and front derail from Evans as they will price match, OK so far.

When the workshop asked what bike it was I said it was Trek Superfly 5 2015 they looked it up and said that I needed a different BB from the standard one and the different BB is going to cost me £25 so here's my question.
The advert on Evans web site says the BB is included but they are going to charge me for a different one so am I entitled to ask for the stock BB that was advertised which is included in the price, or have I the right to ask to just pay the difference?

What do you reckon?

cooldad

What type of BB shell does the bike have?

If it's pressfit the standard XT BB won't work. That's what comes in the box. If the bike needs something else it's not Evans' problem. I'm sure you're entitled to the one in the box, if they are charging you full price for the alternative one.

Why don't you ask them?

skooter

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19772864#p19772864]cooldad[/url] wrote:

What type of BB shell does the bike have?

If it's pressfit the standard XT BB won't work. That's what comes in the box. If the bike needs something else it's not Evans' problem. I'm sure you're entitled to the one in the box, if they are charging you full price for the alternative one.

Why don't you ask them?

I will ring back, I just wanted to know what others thought and I think your dead right I should get the one in the box back..

Cheers.

skooter

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19772864#p19772864]cooldad[/url] wrote:

What type of BB shell does the bike have?

If it's pressfit the standard XT BB won't work. That's what comes in the box. If the bike needs something else it's not Evans' problem. I'm sure you're entitled to the one in the box, if they are charging you full price for the alternative one.

Why don't you ask them?

Not sure on the OE BB for the bike but the one Evans are going to put on is this..
http://www.evanscycles.com/products/shimano/mtb-press-fit-83mm-hollowtech-ii-bottom-bracket-ec045775

I did manage to get through to there workshop and the guy I spoke to first shouldn't have charged me extra so all they will do is swop the BB for the right one when I get there ....sorted

The Rookie

Won't need a BB anyway, just adaptors similar to http://www.evanscycles.com/products/wheels-manufacturing/sram-pressfit-30-to-shimano-24-mm-crank-axle-shims-ec060221

cooldad

The adapters are more expensive than a new BB.

skooter

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19772939#p19772939]The Rookie[/url] wrote:

Won't need a BB anyway, just adaptors similar to http://www.evanscycles.com/products/wheels-manufacturing/sram-pressfit-30-to-shimano-24-mm-crank-axle-shims-ec060221

I wouldn't of known that so another great bit of info.

Cheers