Mountain Bike Reviews Forum banner
1 - 20 of 44 Posts

·
Registered
Joined
·
1,663 Posts
Discussion Starter · #1 · (Edited)
OK, hope you don't find my little experiment too foolish. You are blindfolded so you don't see what frame you are riding, ok no that's stupid, the frame is covered so you just don't see which brand/name it is. The 3 frames have the same fork (6" travel), same shock with similar travel (6") but not necessarily the same rear suspension design. You ride technical trails, steep ups and downs,...

1st frame has 66 Head Angle, 71.5 Seat Angle, 44.0 Wheel Base, 16.9 ChainStay, 22.2 Top Tube and 14.2 Bottom Bracket height.

2nd frame has 67.5 HA, 70.5 SA, 43.8 WB, 17.5 CS, 22.8 TT, 14.0 BB

3rd frame has 67.5 HA, 70 SA, 43.1 WB, 17.1 CS, 22.5 TT, 13.8 BB

The first frame is stable going downhill. The cockpit is short so you feel a bit over the front wheel. It is quite slack in front so it tackles the steep downhill relatively well. You really need to put your weight to the front on steep uphill because the front wheel lifts easily.

So, how do you think the second and third frame will feel like? Are those geometry different enough to make a difference or is it too close that it wont change a thing?

Thanks.
 

·
Registered
Joined
·
1,663 Posts
Discussion Starter · #3 ·
Well you've got quite an eye Shiggy, my mistake, 1st bike Wheel Base is 44 not 44.5! (now corrected below)

So to you those small differences wont make the bikes feel much different once you select the right seat post and stem to position the rider correctly? I would have thought that a very small difference in chainstay might be quite noticeable. Ho well, thanks for you input.

shiggy said:
With each setup to fit the rider, basically no difference.

The stated differences in wheelbase look strange given the other dimensions though.
 

·
Premium Member
Joined
·
48,238 Posts
BanzaiRider said:
Well you've got quite an eye Shiggy, my mistake, 1st bike Wheel Base is 44 not 44.5! (now corrected below)

So to you those small differences wont make the bikes feel much different once you select the right seat post and stem to position the rider correctly? I would have thought that a very small difference in chainstay might be quite noticeable. Ho well, thanks for you input.
The wheelbase numbers still look goofy if the bikes all have the same fork.

6" of travel can mask the small geometry differences fairly easily.
You might notice the longer rear end on #2. Could be more balanced on the climbs.
 

·
Registered
Joined
·
1,663 Posts
Discussion Starter · #5 · (Edited)
Well 2nd and 3rd are "theoretical" based on manufacturer numbers, 1st is measured. So considering the error I made on the 1st, here is a revised version for WB. 2nd should be 43.8 and 3rd should be 43.1 (now corrected below). Does that make more sense? WB could be off by .1-.2 and HA-SA could be plus or minus half a degree wrong but not more. Chainstays don't change.

shiggy said:
The wheelbase numbers still look goofy if the bikes all have the same fork.

6" of travel can mask the small geometry differences fairly easily.
You might notice the longer rear end on #2. Could be more balanced on the climbs.
 

·
Premium Member
Joined
·
48,238 Posts
BanzaiRider said:
Well 2nd and 3rd are "theoretical" based on manufacturer numbers, 1st is measured. So considering the error I made on the 1st, here is a revised version for WB. 2nd should be 43.8 and 3rd should be 43.1 (now corrected below). Does that make more sense? WB could be off by .1-.2 and HA-SA could be plus or minus half a degree wrong but not more. Chainstays don't change.
Every one of the dimensions except the TT length changes as the suspension moves.

I still say the differences are small enough that suspension setup (even if all the same design) and riding style can affect the ride more than the geometry changes.
 

·
Registered
Joined
·
1,663 Posts
Discussion Starter · #7 ·
That is funny Shiggy. I specifically posted the geometry without the bike brand & name in order to get "objective" comments. On the Turner forum (and others as well) for a while now, it is being said that a lot of the rear suspension design is hype and bottom line it is small geometry changes that make a bike feel good or not. On this thread here, although nobody else than you has replied yet, you say that small geometry changes, everything else being equal, wont make much difference!

Well, are we slowly discovering that finally all bikes are relatively equal and everything is hype? You would not believe the varying comments I would have got here already if I had posted the bikes brand & name because the feedback about them is really varied. However, there is one point in that varied feedback which might demonstrate that your opinion is not too far away from reality, when people post feedback, it is usually comparing their old bike to the new bike or comparing different bikes in the same category but with a different fork!

Also, don't forget that I said the three bikes have totally different rear suspension setup, they are in the same range of travel but not the same rear suspension design at all. However, for the last few months, it seems like that is of minimal importance.

Anyway, I hope a few others will chime in with their opinion, I find it kind of interesting but maybe I'm the only one who does! haha

shiggy said:
Every one of the dimensions except the TT length changes as the suspension moves.

I still say the differences are small enough that suspension setup (even if all the same design) and riding style can affect the ride more than the geometry changes.
 

·
Registered
Joined
·
11,763 Posts
Those seat tube angles..

BanzaiRider said:
OK, hope you don't find my little experiment too foolish. You are blindfolded so you don't see what frame you are riding, ok no that's stupid, the frame is covered so you just don't see which brand/name it is. The 3 frames have the same fork (6" travel), same shock with similar travel (6") but not necessarily the same rear suspension design. You ride technical trails, steep ups and downs,...

1st frame has 66 Head Angle, 71.5 Seat Angle, 44.0 Wheel Base, 16.9 ChainStay, 22.2 Top Tube and 14.2 Bottom Bracket height.

2nd frame has 67.5 HA, 70.5 SA, 43.8 WB, 17.5 CS, 22.8 TT, 14.0 BB

3rd frame has 67.5 HA, 70 SA, 43.1 WB, 17.1 CS, 22.5 TT, 13.8 BB

The first frame is stable going downhill. The cockpit is short so you feel a bit over the front wheel. It is quite slack in front so it tackles the steep downhill relatively well. You really need to put your weight to the front on steep uphill because the front wheel lifts easily.

So, how do you think the second and third frame will feel like? Are those geometry different enough to make a difference or is it too close that it wont change a thing?

Thanks.
are going to have you pretty far off the back. Even with a post with no offset the bars are going to be in your lap on all 3 ie climbings going to possible but its gonna suck. Something like a 6 inch trail bike would get you 6 inches of rear travel via a HL four bar suspension with a 68 HT, 73.5 ST, 13.5" BB and 43" wheelbase.
 

·
Premium Member
Joined
·
48,238 Posts
BanzaiRider said:
...Also, don't forget that I said the three bikes have totally different rear suspension setup, they are in the same range of travel but not the same rear suspension design at all...
No, you did not. You wrote this:
"...but not necessarily the same rear suspension design."
Very different meanings.

Years ago a frame builder/magazine writer built a bike with totally adjustable geometry - head angle, seat tube angle, fork rake, BB ht, etc. - to see if an un-rideable bike could be built.

Everything he tried could be ridden. Even a bike with a reversed head angle. Said it was not easy but the rider was able to adapt to the bike in every case.
 

·
Glad to Be Alive
Joined
·
43,009 Posts
with shiggy roughing you up............. I will play nice

#2 and #3 bikes will turn faster...at DH high speeds they won't feel as stable
 

·
Registered
Joined
·
1,908 Posts
I had the same issue recently. I compared the geometry on my current bike with another bike. I bought the new bike but docuemented the geometry of each to find out what was different.
Old bike:
HA 70.5 - SA 72.5 - TT 25.5" - chainstay 16.4" - wheelbase 44.6" - BB height 12.7"
New bike:
HA 70.5 - SA 73 - TT 25.1" - chainstay 16.7" - wheelbase 44.4" - BB height 12.8"

Old bike - smooth and stable at pure XC. Problems with bike control made clearing obstacles and bunnyhopping very inconsistent. Light front end made climbing a problem. Riding postion is stretched but felt quick.

New bike - riding postion is different (handlebars seem higher). Riding position is much more comfortable. Bike control on technical sections is much improved. Bunnyhopping is consistent and effortless. Climbing is much more controlled. Ride seems slower and requires more work.

IMO, small changes in geometry make a huge difference in ride comfort and bike performance.
 

·
Premium Member
Joined
·
48,238 Posts
Lumbee1 said:
...IMO, small changes in geometry make a huge difference in ride comfort and bike performance.
As do the components.
What are the differences in the parts spec? Different forks? Stem length/bar height? Wheels and tires?
Different head tube lengths? It is a part of the frame geometry that is often overlooked.
 

·
Registered
Joined
·
1,663 Posts
Discussion Starter · #14 ·
gunfodder said:
Bike two looks like a Nomad. Those extra long chainstays really stand out.
Please don't start the guessing game! hahaha

I want this thread to remain neutral and as I said below, if I post the bike brand & name everybody will be telling me the three bikes ride "completely" different.

So in your opinion, if the chainstay stand out in bike two, is this good or bad?
 

·
Registered
Joined
·
1,663 Posts
Discussion Starter · #15 ·
Lumbee1 said:
I had the same issue recently. I compared the geometry on my current bike with another bike. I bought the new bike but docuemented the geometry of each to find out what was different.
Old bike:
HA 70.5 - SA 72.5 - TT 25.5" - chainstay 16.4" - wheelbase 44.6" - BB height 12.7"
New bike:
HA 70.5 - SA 73 - TT 25.1" - chainstay 16.7" - wheelbase 44.4" - BB height 12.8"

Old bike - smooth and stable at pure XC. Problems with bike control made clearing obstacles and bunnyhopping very inconsistent. Light front end made climbing a problem. Riding postion is stretched but felt quick.

New bike - riding postion is different (handlebars seem higher). Riding position is much more comfortable. Bike control on technical sections is much improved. Bunnyhopping is consistent and effortless. Climbing is much more controlled. Ride seems slower and requires more work.

IMO, small changes in geometry make a huge difference in ride comfort and bike performance.
Like Shiggy said, it would be nice to know if there are other variables in your comparison like fork, stem&handlebar height, tires, etc. In my little "game" here, I'm comparing frame geometry only. My assumption is that bike 1-2 and 3 would be using the exact same components, fork included. The stem/handlebar could be a bit different to achieve a similar rider position but that's it. The only difference would be geometry and rear suspension design.
 

·
Map Maker
Joined
·
1,244 Posts
BanzaiRider said:
Please don't start the guessing game! hahaha

I want this thread to remain neutral and as I said below, if I post the bike brand & name everybody will be telling me the three bikes ride "completely" different.

So in your opinion, if the chainstay stand out in bike two, is this good or bad?
The longer chainstay should feel more stable and track better through turns.
this is the "NEW" trail bike geometry - short top tube, slack head angle, and a bit longer chain stay to make everything stable. its also "Classic" santa cruz geometry -
they had a big article in MBA last month about the New version of trail bike geometry.
 

·
Premium Member
Joined
·
48,238 Posts
BanzaiRider said:
...The stem/handlebar could be a bit different to achieve a similar rider position but that's it...
The seatpost and saddle position is part of the fit/rider position. I always set my position over the bottom bracket/pedals first. This can change the "effective" TT length. A slacker STA means I need to move the saddle further forward on the post. Effectively shortens the TT length (frame #3 has the shortest effective TT for me). Means a different stem length may be needed.
 

·
conjoinicorned
Joined
·
3,525 Posts
Well, are we slowly discovering that finally all bikes are relatively equal and everything is hype?
i read a lot of your threads banzairider, first off you need a new bike that is plusher out of the box rather than manipulating your poor devinci.. ;) ps. what do you do with all the shocks after you try them?

that said, i could not agree more with your above quote. all bikes in a certain general category (ie. trail, FR, DH whatever) at a certain general price point are created equal. it's 99.5% rider preference, no one can say otherwise if they are honest. as shiggy said, it's primarily the rider, and what is a negative for one person might be a positive for another. this is the exact reason why turner can champion horst link for years, and then switch and go faux bar and equally champion the technology, the two bikes will do what they are intended to do.

as far as geometry, you would notice a small change more easily on the same frame, but two obviously different frames will ride "completely" differently than each other even if they had identical geometry. you can't get around that!!
 

·
Registered
Joined
·
1,663 Posts
Discussion Starter · #19 ·
shiggy said:
The seatpost and saddle position is part of the fit/rider position. I always set my position over the bottom bracket/pedals first. This can change the "effective" TT length. A slacker STA means I need to move the saddle further forward on the post. Effectively shortens the TT length (frame #3 has the shortest effective TT for me). Means a different stem length may be needed.
Good point shiggy, didn't think about the effective length and your right, given the same position above crank then #3 is shortest!
 

·
Registered
Joined
·
1,663 Posts
Discussion Starter · #20 ·
ferday said:
i read a lot of your threads banzairider, first off you need a new bike that is plusher out of the box rather than manipulating your poor devinci.. ;) ps. what do you do with all the shocks after you try them?
Hey thanks, but don't take all my complaining about the Banzai plushness with a grain of salt. I'm convinced 90% of riders would probably say it's incredibly plush. I would not be surprised at all if it is as plush or very close to the Turner and Ellsworth in the same category with the same shock. It is just that I'm a very picky bastard that is looking for the ultimate! I've seen a few here that are like that! hahaha
 
1 - 20 of 44 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top