Follow on - Can a 150mm bike do this: -

diddyfunk

Hi Guys

You have probably seen my other post on 'Can you climb with 150mm traver'.

Do you think i can use aStumpy evo Expert 2011 for events like the S Downs Way and the Trans Wales?

Would it be too heavy etc or suit well?

Many Thanks in advance

Northwind

You definately can. Whether you'll wish by halfway through the second day that you were on a 22lb hardtail is another question though

1mancity2

As Northwind says, just think "it will get me fit" as your lugging it around

diy

Done the SDW100 a few times on my old Spesh Enduro which is probably 2kg heavier than I would have liked.

but its the geometry that does you in rather than the travel or weight.

njee20

You definitely can. Whether you'll wish by halfway through the second day that you were on a 22lb hardtail is another question though

This.

Are you gonna start a thread for every concievable use!? If so the answer will always be the first 3 words above, the intonation implied by the italics are significant!

DodgeT

A rigid bike can do pretty much the same as a 200mm downhill machine. The difference is how best suited, therefore easily, the bike and you will cope with the particular terrain at the time.
End of the day, you can "do" anything, on anything, just some more easier than others.

Awaits to be shot

njee20

That's what everyone's saying Dodge...

DodgeT

I know, I just wanted a go too
Plus, the more its said, maybe more people may get it.

njee20

So why "Awaits to be shot " :?

DodgeT

I'd originally put a comment about SS in, cause I thought it had been mentioned. Then when I re-read, i realised it was the drivel in another thread, so I removed it. But then thought i'd leave the shot comment as surely someone will come along to say you can't go uphill on a downhill bike etc.

Anonymous

A long travel full sus bike (are we talking full sus here?) is likely to have a gearing set up that isn't suited for a distance XC ride, probably 2 or 1 ring, so you'll be spinning out a lot or not have enough for the ups. Can go triple on it but then it may not be quite right for AM/DH stuff or you end up wanting to fit a bash or chain guide.

Northwind

deadkenny wrote:

A long travel full sus bike (are we talking full sus here?) is likely to have a gearing set up that isn't suited for a distance XC ride, probably 2 or 1 ring, so you'll be spinning out a lot or not have enough for the ups.

Uhhhh no, not so much. 2x9 gives you all the lows and almost all the highs, you lose the very top 2-and-a-half gears comparing 36 with 44. 36-11 doesn't spin out til you're approaching 30mph so you won't spin out a lot- you do it very occasionally on tarmac or dirt roads.

NatoED

I think you worked that out wrong 36 11th is only 23MPh at a cadence of 90 Rpm . 44 - 11th at 90 Rpm is 28 MPh . RPM greater than 90 becomes inefficient for DH use . you would have to be spinning at over 120 rpm to get 30mph out of a 36 tooth .


for reference a 36 - 11 ration is 88 inches . multiply that by your rpm then divide by 336 to get your mph .

44-11 is 108 inches .

supersonic

36-11 doesn't spin out til you're approaching 30mph

Sounds correct to me!

felix.london

NatoED wrote:

I think you worked that out wrong 36 11th is only 23MPh

I get over 23mph in 32:11

Northwind

My suspicion is that your gear-inch calcs there are for small tyres, or possibly just for the rim... But I can spin my xc bike out of its 36T ring on the big hill down to my work at 27mph, and I'm not a particularily fast spinner because of my hip, a fully able rider should be capable of more. How often do you think you'll be wanting to maintain a descent over 27mph on rides like this? And how much will you care if you do, but can't?

paul.skibum

Why we talking about gear ratios? A new Stumpy Evo comes with a 2 10 gear set up doesnt it? That will have plenty of ratios for a long ride and the Stumpy is a fine trail machine capable of covering the miles (albeit less so than it used to be but still good)

NatoED

I stand corrected I re- entered the figures for the tyre size .

What would you guys say your Rpm is then to be spinning out? I find that spinning more than 100 is spinning out . that would make 36 - 11 to be doing 30 mph.

but for DH you don't want to be on the verge of spinning out do you ? you want to be able to accelerate or put any power down as your already on the end of your top speed . 40 tooth would seem a better size for DH riding .

It's not so much if you can or can't it's weather it efficient to do so . if your right that a 36 tooth would be ok for DH they why do DH riders (and bikes) use 40 - 44 tooth chain rings ?

Northwind

Downhill, sure... Though that's course specific (my DH bike has a 33T on it but only so I can ride it back up On the way down I worry more about slowing down than speeding up )

Not really sure what my RPM is, never had a bike with a cadence meter. I can see 110rpm on a gym bike but real world's not the same, certainly feels a lot slower anyway.

felix.london

The DH bike I'm getting - the manufacturer gives you a choice of 5 different chainsets to choose from - all 36T rings though.

And I'm going for the 12-27 cassette - cos as Northwind says I'm gonna be concerned about slowing down!

NatoED

LOL you need HS33 then

njee20

Why do you keep talking about DH bikes NatoED?! We're talking about a trail bike, and the suitability of it. Efficient cadence for DH racing is irrelevant!

FWIW I run a 36t single on my XC race bike and I've done nearly 30 on the flat, and happily over with a bit of gradient assistance. No idea of the cadence, but I can happily spin 120rpm on the road if I need to.

The gearing won't be a limiting factor on the Stumpy for things like the SDW.

NatoED

ask north wind he started it !

Northwind

I really didn't!

NatoED

yes you did

Northwind

NatoED wrote:

but for DH you don't want to be on the verge of spinning out do you ? you want to be able to accelerate or put any power down as your already on the end of your top speed . 40 tooth would seem a better size for DH riding .

It's not so much if you can or can't it's weather it efficient to do so . if your right that a 36 tooth would be ok for DH they why do DH riders (and bikes) use 40 - 44 tooth chain rings ?

NatoED

:roll: I was joking with my comment .