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SNGLSPD
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Discussion Starter · #1 ·
As I understand it the lower hole is for 4"mode but does the HA and BB height change between settings?
Sure I could just measure it but what fun is that
 

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Bike to the Bone...
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KgB said:
As I understand it the lower hole is for 4"mode but does the HA and BB height change between settings?
Sure I could just measure it but what fun is that
No, there isn't any noticeable change in geo from 4" to 5" settings. I leave the settings at 5" settings and off I go!
 

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rzozaya1969 said:
No, there isn't any noticeable change in geo from 4" to 5" settings. I leave the settings at 5" settings and off I go!
Actually, that's not true, the 4" setting steepens the head-angle quite a bit. Changing to the 4" setting also makes the rear end much less active as you change the way the swingarm directly engages the shock (there's a bit of a bend when you use the 4" setting). The ML is really designed for the longer stroke but has the option for the shorter one just in case you prefer a less aggressive style of riding.
 

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CranxOC said:
the 4" setting steepens the head-angle quite a bit.
maybe if you think of it in terms that with less sag you end up with steeper angles. But, I don't think the geometry changes when you go from 5" to 4" mode; just the leverage.
 

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dulyebr said:
maybe if you think of it in terms that with less sag you end up with steeper angles. But, I don't think the geometry changes when you go from 5" to 4" mode; just the leverage.
I once changed to 4" mode, I didn't notice any geometry change. So I just keep the 5" settings...

Cranx... what happened to your avatar?
 

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I thought the head tube angle changed? 4" mode, HA = 70.5, 5" mode, HA = 69.25. The ML seems quicker in the 4" mode. I actually really like the way the ML rides in the 4" mode.
 

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dulyebr said:
maybe if you think of it in terms that with less sag you end up with steeper angles. But, I don't think the geometry changes when you go from 5" to 4" mode; just the leverage.
Agreed....angles don't change when un-sagged. Titus reccomends 15psi less in 4" mode and there is less travel too, if you just swap holes then the rear end sits higher in it's travel creating a steeper feel.
 

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CranxOC said:
Actually, that's not true, the 4" setting steepens the head-angle quite a bit. Changing to the 4" setting also makes the rear end much less active as you change the way the swingarm directly engages the shock (there's a bit of a bend when you use the 4" setting). The ML is really designed for the longer stroke but has the option for the shorter one just in case you prefer a less aggressive style of riding.
:confused: Cranx, do you want to take a second pass at that.I don't follow?
 

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JTBAZ said:
I thought the head tube angle changed? 4" mode, HA = 70.5, 5" mode, HA = 69.25. The ML seems quicker in the 4" mode. I actually really like the way the ML rides in the 4" mode.
I believe this explains it all.

If you move the bolt from one hole to the next and pay attention to the front end, you can actually see that the angle is, in fact, steeper. By moving that bolt you're pushing the whole front triangle forward thus changing the angle.

As for my avatar, it was kinda cool but was also a little on the dark side so I decided to change it. The star's OK but I'm exploring other options as well. :)
 

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not so according to the man...

TitusChris said:
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The last item had to do with geometry questions. First, I will be adding another geometry chart in the near future to the Titus website that shows the geometry with a 5" travel fork. The actual seat tube angle will be slightly steeper then 72 degrees. As for the suggestion to steepen the seat angle so that it sits closer to 73 when the bike is at 5" would have the affect of lengthining the wheelbase and changing the general handling and feel of the bike for it's intended use. The design intent of the Moto-Lite is to have it be considered a Racer-X on steroids. More travel and slightly more stable handling, but with pedalling performance and a frame weight that is very close to what you get with the Racer-X. It is my intent that the Moto-Lite be used with a travel adjust front fork such as a Fox Talas, Rock Shox Revolution, Manitou Minute, etc. The rear travel adjust does not change the geometry of the bike at all, so any angle changes are purely because of a change in fork length. We have many customers that race the Moto-Lite in 24 hour events. For these situations, the 70.5/73 seat tube angle is perfect. For general trail riding I like to run the fork at 110-115mm which sets the angles at about 70.3/72.8. The only time I run at a full 5" in the front is when I am doing agressive trail riding where the slacker 69.5 head angle is a plus. In these situations, the 72 seat angle is also a plus. I someone is puting a 5" or longer not adjustable travel fork on the front, and likes the slower handling, then the affective seat angle can easily be compensated for with a zero offset post and/or the seat slid a little more forward on the rails.
...
full post here: http://forums.mtbr.com/showpost.php?p=1580756&postcount=64

.
 

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salimoneus said:
Next time I get an opportunity, I'll do some angular testing on the HA in 4" and 5" modes as I don't believe there's any way that moving the throw doesn't change the HA. If you think about it logically, all of the tubes are in a fixed position so, if you modify one point on the bike and don't change anything else, then something has to change somewhere.

I'm not trying to be contentious here, I simply can't believe that everything stays the same when you move the shock bolt. This is especially true considering I've raced the thing in the 4" mode and it had a VERY different feel from the 5" mode.

Like I said, next time I'm around someone who has the tools, I'll make the adjustments and measure the difference (assuming there is one of course) and will report back.
:)
 

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CranxOC said:
Next time I get an opportunity, I'll do some angular testing on the HA in 4" and 5" modes as I don't believe there's any way that moving the throw doesn't change the HA. If you think about it logically, all of the tubes are in a fixed position so, if you modify one point on the bike and don't change anything else, then something has to change somewhere.

I'm not trying to be contentious here, I simply can't believe that everything stays the same when you move the shock bolt. This is especially true considering I've raced the thing in the 4" mode and it had a VERY different feel from the 5" mode.

Like I said, next time I'm around someone who has the tools, I'll make the adjustments and measure the difference (assuming there is one of course) and will report back.
:)
sorry man, but you are not correct.
 

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CranxOC said:
Next time I get an opportunity, I'll do some angular testing on the HA in 4" and 5" modes as I don't believe there's any way that moving the throw doesn't change the HA. If you think about it logically, all of the tubes are in a fixed position so, if you modify one point on the bike and don't change anything else, then something has to change somewhere.
...
you are right, something has to change, but why would you assume it must be the HA or STA? i'm no mechanical engineer, and although the linkage looks simplistic there is a lot going on there with leverage and such...
 

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so I made you a picture. look at the red arc, the radius is equal to the shock length.. notice that if you mounted the rear of the shock any place on that arc the swing link position would not change in relation to the frame. thus no change in ride hight. but as you move down the arc you will have a lower leverage ratio, thus less travel.
 

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SNGLSPD
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Discussion Starter · #16 ·
seems like

demo_slug said:
so I made you a picture. look at the red arc, the radius is equal to the shock length.. notice that if you mounted the rear of the shock any place on that arc the swing link position would not change in relation to the frame. thus no change in ride hight. but as you move down the arc you will have a lower leverage ratio, thus less travel.
It seems like you could accomplish the same by adding a little more air pressure.
Tomorrow I will measure both settings HA and BB height and measure the amount of travel with no pressure in the shock.
This will clear up any speculation.
 

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KgB said:
It seems like you could accomplish the same by adding a little more air pressure.
Tomorrow I will measure both settings HA and BB height and measure the amount of travel with no pressure in the shock.
This will clear up any speculation.
sorry you lost me. the same what?

sure you can change you geometry by changing your sag. but you can't change you leverage ratio.

the point of my cartoon. was to demonstrait that you can change the leverage ratio with out changing the geomtry at full extension.
 

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Sorry Cranx, I side with the others. I think the only thing that changes is the angle at which the shock lies. The changes in the chart on the titus website are reflecting with a taller fork.
 

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mcgrath said:
Sorry Cranx, I side with the others. I think the only thing that changes is the angle at which the shock lies. The changes in the chart on the titus website are reflecting with a taller fork.
Hey, if I'm wrong I'm wrong and will admit it in a heartbeat however, I did go and pull the bolt today and used a level to see if there was any difference when the shock was moved from one position to the next and the bubble was definitely in a different place. I know, this is a completely unreliable test but, my eyes and the way my bike feels when in 4" mode are telling me something different so I'm going to have to actually get someone who can actually mathematically measure such things to do so in order to satisfy my own curiosity.

Like I said earlier, I'm not saying I'm right but I'm not really sure I'm wrong either. I'll try to find out soon so I can either come on here and admit I'm wrong or give a scientific reason as to why I'm not.
 
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