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2009 giant glory dh or 2009 trek session 88?

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2009 giant glory dh or 2009 trek session 88?
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flag ctd07
Posted: Jan 3, 2009 at 16:18 Quote
OG4LIFE wrote:
ctd07 wrote:
m47h13u wrote:


Well that about sums up what I was thinking all along, sadly I can't put crap into words without a bit of rage.
Salute


Anyone ever thought... maybe the Trek requires a shock tune, not to give the bike 'super awesome all-exceeding performance', but to compensate for the fact that the shock is floating, so when it tries to extend after being compressed, it will be fighting against itself to an extent - pushing down on the swingarm shock mount will effectively try to compress the shock still - so the rebound force needs to be higher and the the compression damping more, as the shock will also try to compress itself a percentage when compressing.

In essence its a different science, with more un-sprung weight [the WHOLE suspension linkage and the WHOLE shock too] the shock has to not only cope with a larger amount of inertia from the design but also fights itself to an extent - basically, it needs to be custom tuned to work properly and benefit from its theoretical advantages, as standard available shocks aren't designed to 'float'!

Since the top pivot moves at a much greater rate/distance, I wouldn't think it needs a ton of extra tune, but you may be right. I have been dealing with this sort of design in snowmobiles for a few years and was curious why it hadn't made its way into bikes. This design helps make a shorter shock "perform" with a longer wheel travel and be softer for the small bumps(the lower mount is moving down as the top pivots down), then (due to different ratios between the top pivot and lower mount as the suspension cycles) the suspension will stiffen up very progressivly towards the bottom of travel. I see it as an extra mechanical progression of the suspension, besides the angle of shock and natural spring/air shock progression. I can see where it will allow for more flexibility in shock tune to have a DH sort of setup and still maintain excellent bottoming resistance. I wonder, however, if it can compete with the efficiency of the VPP/DW types of suspensions. I am definetly not discounting it and it may be better, so I will be waiting eagerly to hear how or if it can blast out of a corner like a Sunday or Glory...after all aren't races won in the cornersWink Also how well it pedals when that is required. I do see the design to possibly have an advantage when it comes to traction under braking, since the shock is "floating"--seemingly better responding to rear wheel feedback(depending on the tune of course). Maybe a hybrid would be the best of both worlds! Engineer types--have I missed anything?

yeh, I guess the damping has to be lowered overall, as the shock will compress slower through its travel than a standard setup under the same impact force.

The 'ABP' [active braking pivot] bumf is just because the design effectively has a very 'late' Horst pivot concept - any design where there is a pivot on the chainstay (or in the Trek's case, right on the axle) will transfer the braking forces off of the chainstay and into the seatstay link, causing that to move instead of the chainstay - which, if the rocker link [and all other links and pivot points] is positioned correctly, causes such forces to be implied 'perpendicularly' (trans-axially?) into the rocker links pivot and thereby into the frame, effectively removing them from the shock.

basically, the Trek Sesh 88 has a single pivot 'Horst' style design with a floating shock.
flag OG4LIFE
Posted: Jan 3, 2009 at 17:40 Quote
ctd07 wrote:
OG4LIFE wrote:
ctd07 wrote:

Salute


Anyone ever thought... maybe the Trek requires a shock tune, not to give the bike 'super awesome all-exceeding performance', but to compensate for the fact that the shock is floating, so when it tries to extend after being compressed, it will be fighting against itself to an extent - pushing down on the swingarm shock mount will effectively try to compress the shock still - so the rebound force needs to be higher and the the compression damping more, as the shock will also try to compress itself a percentage when compressing.

In essence its a different science, with more un-sprung weight [the WHOLE suspension linkage and the WHOLE shock too] the shock has to not only cope with a larger amount of inertia from the design but also fights itself to an extent - basically, it needs to be custom tuned to work properly and benefit from its theoretical advantages, as standard available shocks aren't designed to 'float'!

Since the top pivot moves at a much greater rate/distance, I wouldn't think it needs a ton of extra tune, but you may be right. I have been dealing with this sort of design in snowmobiles for a few years and was curious why it hadn't made its way into bikes. This design helps make a shorter shock "perform" with a longer wheel travel and be softer for the small bumps(the lower mount is moving down as the top pivots down), then (due to different ratios between the top pivot and lower mount as the suspension cycles) the suspension will stiffen up very progressivly towards the bottom of travel. I see it as an extra mechanical progression of the suspension, besides the angle of shock and natural spring/air shock progression. I can see where it will allow for more flexibility in shock tune to have a DH sort of setup and still maintain excellent bottoming resistance. I wonder, however, if it can compete with the efficiency of the VPP/DW types of suspensions. I am definetly not discounting it and it may be better, so I will be waiting eagerly to hear how or if it can blast out of a corner like a Sunday or Glory...after all aren't races won in the cornersWink Also how well it pedals when that is required. I do see the design to possibly have an advantage when it comes to traction under braking, since the shock is "floating"--seemingly better responding to rear wheel feedback(depending on the tune of course). Maybe a hybrid would be the best of both worlds! Engineer types--have I missed anything?

yeh, I guess the damping has to be lowered overall, as the shock will compress slower through its travel than a standard setup under the same impact force.

The 'ABP' [active braking pivot] bumf is just because the design effectively has a very 'late' Horst pivot concept - any design where there is a pivot on the chainstay (or in the Trek's case, right on the axle) will transfer the braking forces off of the chainstay and into the seatstay link, causing that to move instead of the chainstay - which, if the rocker link [and all other links and pivot points] is positioned correctly, causes such forces to be implied 'perpendicularly' (trans-axially?) into the rocker links pivot and thereby into the frame, effectively removing them from the shock.

basically, the Trek Sesh 88 has a single pivot 'Horst' style design with a floating shock.

I'll have to take your word for it on the Horst setup--having a hard time with the visualization with out a pictureSmile With what you have stated, then would you figure a VPP style with a Horst to be even better, since there is another place to scrub the braking forces(the VPP link) or, in other words, 1 less chance for the rear to lock up under brake load?
flag fugazzi
Posted: Jan 3, 2009 at 17:42 Quote
Both nice bikes save the cash and get a Glory! Or you can buy the newest trend on the market and spend more cash and take parts off it and than spend some more cash. Glory tested and proven already who knows if the 88 will cut it in the end.
flag OG4LIFE
Posted: Jan 3, 2009 at 17:44 Quote
Another thing that I see is that after checking out some lighter components for my bike, it is rather challenging to find lighter parts that can stand up to DH/FR abuse, so if a manufacturer can offer a weight reduction built into its frames AND offer a decent warranty on that frame, it may be worth the extra $1500 in the long run. Just an observation.
flag downhill101
Posted: Jan 3, 2009 at 17:52 Quote
butters88 wrote:
k so i have to decide on what bike to get this season, im only saving right now. The glory dh is 5200 and the terk session is 6700. What makes the trek sooo much more expensive? I know the trek is lighter but is that really worth 1500 dollars? the parts on both are top notch, and both have good suspension designs. im leaning towards the giant. any opinions? anything ive missed? thanks.
if your getting a glory wait till 2010 for the new one that will be out, but right now the 88 is alot nicer of a bike than the glory out right now
flag fugazzi
Posted: Jan 3, 2009 at 18:03 Quote
My Glory weighs 40 with a few mods which is very respectful I trust every part I have on it to last. I rode a glory this summer before i bought it and it was very comparable to my Sunday. I swear by the Maestro design and DW link, I have not ridden the Session 88 so I will not bash it. To say that a Glory DH is not a full on racing machine is a retarded comment.
flag wildbrian
Posted: Jan 3, 2009 at 19:59 Quote
To the people above me, he already decided. Look at the 4th or 5th page(i think) to see which one he chose cuz i forgot. And to the thread author you should change the title to glory vs session 88 or giant glory and session 88 discussion or something like that.
flag veet-88
O+
Posted: Jan 3, 2009 at 20:17 Quote
konakid8 wrote:
get the 88!!!tup tup

Real handy advice there guy any reasons to back that up? or any experience with either bike?

Ryan
flag twntysx
FL
Posted: Jan 3, 2009 at 20:21 Quote
Glory DH fo sho!!
Maestro is unbeatable
Its also got a rlly low center of gravity so its way easeir to throw it around
flag freerider4lyfe
Posted: Jan 3, 2009 at 20:23 Quote
i was in the same position as you, until today when i found out i can get an amazing deal on the glory, but also i found out the glory has lifetime warrenty i think, which is something it has over the session 88
flag OG4LIFE
Posted: Jan 3, 2009 at 20:52 Quote
wildbrian wrote:
To the people above me, he already decided. Look at the 4th or 5th page(i think) to see which one he chose cuz i forgot. And to the thread author you should change the title to glory vs session 88 or giant glory and session 88 discussion or something like that.

I realize he has decided, but some others have not and the thread will die sooner or later. Those interested can come here and gather some good thoughts and insights towards their next purchase. Great information from almost everyone. I on the other hand would like to gain as much knowledge as I can about where the future of bike design is headed...is it better or a hype job??? I don't know. Do you have nothing to learn?

40lbs IS very respectable.
flag PedalUpBombDown
Posted: Jan 3, 2009 at 20:58 Quote
I haven't ridden either, but one thing I do know is that I'd never spend that money on the Trek. When I first saw the MSRP and the parts list, I was dumbfounded at how they matched so I did some calculations. After finding the MSRP of pretty much every part on the bike, I realized that Trek is trying to charge people just under $3500 for the frame and rear shock alone. That's when I learned the reason they aren't selling a frame only option. Personally, I think if everyone knew how much Trek wants for the frame, it wouldn't be anywhere near as popular as it is to all the 14-year-olds dreaming of having one. Don't get me wrong, I'm sure it rides great, but I personally say it is way over priced. If you compare it to every other $3500 frame with that build, IMO, it gets its ass kicked hard.
flag wildbrian
Posted: Jan 3, 2009 at 21:01 Quote
OG4LIFE wrote:
wildbrian wrote:
To the people above me, he already decided. Look at the 4th or 5th page(i think) to see which one he chose cuz i forgot. And to the thread author you should change the title to glory vs session 88 or giant glory and session 88 discussion or something like that.

I realize he has decided, but some others have not and the thread will die sooner or later. Those interested can come here and gather some good thoughts and insights towards their next purchase. Great information from almost everyone. I on the other hand would like to gain as much knowledge as I can about where the future of bike design is headed...is it better or a hype job??? I don't know. Do you have nothing to learn?

40lbs IS very respectable.
I also realize that this thread will die, i am surprised it hasn't already. As for the future of bike designs there are other threads for that. Also i see what you mean about this being a useful thread for people that have the same dilemma as the thread author.
flag myarmisonfire
Posted: Jan 3, 2009 at 21:16 Quote
I don't know if it has been mentioned or not in the posts but Giant makes the Session 88 for Trek...

 


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