Frame geometry?

Oxygen Thief

Indeed it will. Got you. So how can people say then that tighter angles = more aggressive?

The GT has slacker angles than the others, especially more so with the longer fork travel, but is more aggressive? The Giant should be more 'chuckable' but it's prob the longer wheelbase that stops this.

It looks like it's not very simple at all is it? It is the 'aggressive' word that's causing me some confusion I think as somebody said.

Oxygen Thief

Hang on! After playing with that I think I had slacker and tighter back to front?!?!

I would have said 67 is tighter than 71?

supersonic

Slack angles are less. If measured like normal.

As has been said, aggressive can mean more than one thing.

Northwind

Also remember that sometimes the claimed numbers are just plain wrong- and I don't just mean taking into account sag etc, sometimes there's a difference in seattube vs headtube angle which can't be affected by changing any other parts.

Oxygen Thief

Bloody hell! No wonder I was getting confused. I would have said a 45 degree angle is tighter than a 90 degree angle, just because well it makes sense.

Right so slacker angles are smaller numbers. Okey dokey. Ha. So pretty much everything I said above I was looking at the wrong thing. Nobody picked up on any of them though?! I said the Giant has the tightest angles, when it actually has the slackest angles. Granted that's not taking the fork length into play which I now know to do.

BigStu2

jonbonjovial wrote:

There's way too much confusion for me. That Scott has a head angle of 71 on the large, the GT has 71 and the Giant 70.5

Seat angle - Scott 73, GT 73.5 and Giant 73.

There's no wheelbase as far as I can see for the Scott so going on top tube, the Giant has longest, with the GT and Scott about 20mm shorter.

So would I be right in thinking that the top tube angle being more upright in the Scott and GT makes you kind of lean forward more, or shall we say forces you more naturally to have an aggressive stance, attack position friendly sort of?

The seat angle, again the GT is more upright forcing you forward on the bike? Attacking stance again.

Top tube length, shorter on the GT and Scott so again same kind of thing, also smaller bike more than likely with shorter wheelbase meaning easier to throw about. Giant longer so more 'comfortable' ride, rides the bumps a bit better in XC on the flat at speed?

Right tracks?

Top tube length is really the only thing, combined with the stem length that determines how far you lean forwards, the (slackness) of the head angle doesn't really have anything to do with how far you lean forward, quite often bikes with slacker head angles have a slightly shorter toptube anyway to counteract the longer fork that they use , often up to 140mm, think Marin rocky ridge ect.
The two bikes you are considering will deliver pretty much the same level of ride quality and it will come down to things like the fork, wheels, tyres and if your running a wide riser bar or a narrow flat xc bar that will determine how aggressive or how racey the whole ride will be.
For the record I have had a 2001 Norco rush, with a 575mm top tube, 71deg headtube and an 80mm fork, it came standard with a 90mm stem, back then I didnt understand a thing about bikes , I sat slightly upright and compared to my road bike which was very laid out, I believed I was loosing power by not being (aggresive) so I threw on a 120mm stem to mimic the roadride...needless to say it handled like shite but I was very fast on flat fireroads :roll: Next bike was a medium sized specialized epic with a 100mm stem and a 598mm top tube (71deg headtube, 100mm fork) very streched out (same combined length( TT/ stem) as the norco but the longer wheelbase made it more stable), went to a 90mm stem, much better, but still a race type streached out ride, Next bike was a 2008 rocky ridge, 575mm top tube 60mm stem (68deg headtube 140mm fork, 711 mm riserbar), same length wheelbase as the epic, heres where things get interesting, the short top tube that once was considered a hinderence to speed was no longer a worry as I had over ten years of quality riding in my legs, the longer fork and slacker head angle allowed me to scream past anybody downhill if they were riding a standard type mtb (80mm fork a bike with conventional geometry, ie 71deg head tube) and narrow handle bar ect.
Current bike is an Orange five ( 585mm top tube, 67deg headtube, slightly longer wheelbase and 140mm both ends), it leaves the marin for dead on the down hills and pretty much everywhere else, it all comes down to the quality of the parts you choose to hang off the bike as much as the geometry. All I know is that this is the bike I wanted all along but If I had it back then I wouldn't have appreaciated how good it is but then I cant remember having a bad day on any bike I've owned, so in your first few years of riding I dont think geometry plays so big a role in the day to day life of getting out for a ride, (Unless your up at Whistler)
Dont get too hung up on geometry, get a bike and get out and ride with your mates and have a blast.

Oxygen Thief

Cheers for that mate. Interesting read. I was mainly asking just out of pure interest, I like to know a lot about the things I am into and I'd seen a lot written about frames so thought I'd ask. I agree with what you say as a beginner just get out there. It will prove useful in the future the knowledge no doubt though.

Cheers