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  1. #1
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    Longer susp travel Trance?

    Is this a bad idea?

    Get a slightly longer rear shock with slightly more travel, lets say 10mm more travel in the shock. This change would probably result in about 30mm more rear wheel travel. Maybe the rear would now have about 5 inches (125mm) travel.

    Then install a 130mm travel front fork. Now the Trance would be about 5 inches travel front and rear. The longer rear shock and front fork should maintain the original steering geometry while providing more bottom bracket ground clearance (which I seem to need).

    Thanks for any thoughts.

    Terry

  2. #2
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    Not sure the linkage will allow that... the rocker (upper link) will likely hit the seat tube. The lower link almost touch the bb shell with the stock setup...

    Also, you might break your frame when coming to full compression because when you cycle the rear end (without shock mounted) you clearly see that the upper link comes really close to the seat tube when fully compressed...

    Why just don't get a Reign if you want more travel?

  3. #3
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    Sorry to burst your (excelent thought) bubble, but I sincerely don't think it work. There's room between the bottom swingarm and the BB, but I think you would need to make special rockers to accomodate the longer shock. You could try a set of REIGN rockers, but more than likely they would make the travel 6" as with the REIGN. If you have the "toys" around it's worth a go.
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    Quote Originally Posted by BigJay
    Not sure the linkage will allow that... the rocker (upper link) will likely hit the seat tube. The lower link almost touch the bb shell with the stock setup...

    Also, you might break your frame when coming to full compression because when you cycle the rear end (without shock mounted) you clearly see that the upper link comes really close to the seat tube when fully compressed...

    Why just don't get a Reign if you want more travel?
    Thanks for your input. I need to take a *much* closer look at the clearances. I have cycled the rear susp with the shock removed, but at the time was not looking at the rockers.

    I can't get a Reign, already have the Trance. BTW, I really like it and am having more fun with it than I ever had with my NRS.

  5. #5
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    Hi to all of you,

    this is my first post here, but i'm reading and enyoing the forum for some weeks now.
    I got a Trance two month ago and this is the best crosscountry fullsuspension i have ridden so far.
    I like the way the rear suspension works and eats up mostly everything without bobbing when going uphill seated.
    Last week i removed the air of the fox damper and measured the maximum travel of the rear wheel. I got 100mm when the damper is completely compressed.
    I never use the full travel when running the recommended sag, there are 2-3mm left at the damper shaft.So i'm running about 90mm.I was quite impressed cause the rear suspension feels more like 120mm when riding agressive.....

    In the front i'm running a fox vanillaRLC 2006 set to 120mm travel.

    As i'm mostly riding cross country and touring this is enough to soak mostly everything.
    But sometimes i join a group that rides a lot more aggressive and a little bit more travel in the back would give some extra plushness when doing higher drops and riding through the rock gardens.

    I found the website of https://www.betd.co.uk/ making linkages for older giant bikes.
    I contacted Dan of BETD and made some suggestions about making an adjustable linkage for the Trance modells.
    My idea was to have an excentric plate offering different settings that provide a little more travel up to 130mm and also the possibility to adjust the headangle depending on the built in fork and the preferences of the rider.
    Transmission ratio of the original setup is 2,85. Rising to 120mm travel with the same damper lenght would give a transmission ratio of 3,42 which is very high...
    Also the system has to be run in its recommended sag to work well.That means the linkage has to be in an defined angle at its sag.This will lead to problems when running a longer damper e.g. 190mm.

    I have sent Dan some detailed pictures of the linkage and the clearance around and he will contact GIANTS UK representative to get a Trance for testing and maybe building a prototype adjustable linkage.

    I do not know if Dan is reading here in the forum, but i could send him a link to this thread if enough other riders are interested to have an adjustable linkage for the Trance. I would love to have it, so i would not have to think about buying a Reign for the more agressive rides.

    I think that would make the Trance the best allround bike you can ride. What do you think?

    Last edited by zack; 10-12-2005 at 09:53 AM.

  6. #6
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    Quote Originally Posted by zack

    I think that would make the Trance the best allround bike you can ride. What do you think?

    I would be interested in adjustable travel rear susp.

  7. #7
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    Why not have such a thing in Reign ?? As the saying goes: 'The more travel the better'
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    Quote Originally Posted by goRz
    Why not have such a thing in Reign ?? As the saying goes: 'The more travel the better'
    shure, this would also be an option for the Reign, but i thought more about a downgrade to lower the travel to make it more crosscountry like

    So there are 2 options to have a suspension setup between crosscountry/touring and freeride:
    Upgrade the Trance to get slightly more travel at the back (120-130mm).This will lead to a higher transmission ratio-not so good in general, but i think the fox float is able to handle very high pressures (max. pressure is 300psi, i'm currently running 160psi at a weight of 90kg.)

    Downgrade the Reign to run between 100-130mm travel.
    I'm not shure about upgrading to higher travel over 150mm. Maybe the frame should be a little stiffer? (btw. i love the Trance also because of its great lateral stiffness-simply point and go anywhere. The Reign seems to have the same mainframe with a slightly stronger rear triangle).

    Anyway, if Dan of https://www.betd.co.uk/ could offer some adjustable rockers for both the Trance and Reign we all would love that i guess
    Hope he will get a Trance bike for testings from Giant UK and i receive message from him in the next time...

    btw, does anybody know if there is a way to reduce the lenght of a fox float 190mm?
    If that would be possible i could try to modify the lenght to 170, modify the linkage of the Trance a little bit and try how it works.
    Last edited by zack; 10-12-2005 at 12:42 PM.

  9. #9
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    Quote Originally Posted by granny.gear
    Save the effort.

    Get a proper 130mm Fox fork. Perhaps the Float RLC.

    The Maestro suspension is spot on, meaning you will feel like your getting more travel than it really has.

    Increase the travel in the front fork and it will slacken the head angle to a respectable all-mountain angle and you will have a smile on your face.
    you're right. i get about 90mm travel at the back when adjusting to the recommended sag.
    Also i'm running a fox vanilla set to 120mm.
    This setup feels great, steering is balanced and still responsive (in my opinion better as running with the fork set to 100mm) and i never have the feeling to reach the limits of the rear suspension, it soaks what it gets.....

    Although i want to know how it works with a travel set to 120-130mm in the back
    Last edited by zack; 10-13-2005 at 12:11 AM.

  10. #10
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    I don't know if this is a good idea.

    Differently from other designs, the Maestro/DW-Link is very sensitive to pivot placement, shock leverage and suspension rate. Actually suspension rate and shock leverage is what make these bikes pedal and ride as they do.

    Changing to a different shock/plates can affect the ride characteristics and much probably in a negative way. Just snoop around the Ironhorse forum where Dave Weagle (the inventor of this system) posts from time to time and you'll know what I mean.

    BTW... Ironhirse had the adjustable travel Hollowpoint and they dropped the idea this year. DW bikes now are set to a fixed travel where they work optimum.

    It's worht a try but I think the outcomes will not be as good as the original thing. I'd like to be wrong on this one.
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  11. #11
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    Quote Originally Posted by Warp2003
    I don't know if this is a good idea.

    Differently from other designs, the Maestro/DW-Link is very sensitive to pivot placement, shock leverage and suspension rate. Actually suspension rate and shock leverage is what make these bikes pedal and ride as they do.

    Changing to a different shock/plates can affect the ride characteristics and much probably in a negative way. Just snoop around the Ironhorse forum where Dave Weagle (the inventor of this system) posts from time to time and you'll know what I mean.

    BTW... Ironhirse had the adjustable travel Hollowpoint and they dropped the idea this year. DW bikes now are set to a fixed travel where they work optimum.

    It's worht a try but I think the outcomes will not be as good as the original thing. I'd like to be wrong on this one.
    warp2003, thanks for pointing me to the Ironhorse forum.
    I also thought that leverage position is critical at these VPP designs, but slightly increasing transmission ratio to get 120mm travel using the same shock lenght (165mm) wouldn't change the leverage so much i guess.
    hmmm....., i guess i will have to machine some shock plates and try how it works.

  12. #12
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    Quote Originally Posted by zack
    warp2003, thanks for pointing me to the Ironhorse forum.
    I also thought that leverage position is critical at these VPP designs, but slightly increasing transmission ratio to get 120mm travel using the same shock lenght (165mm) wouldn't change the leverage so much i guess.
    hmmm....., i guess i will have to machine some shock plates and try how it works.
    You want 120mm rear travel, right?? (Who doesn't?? )

    Your shock now is a 38mm (1.5")stroke shock, that with a 2.85 ratio gives 108mm of total travel.

    To keep leverage equal, your one and only chance is to increse both shock and travel. Changing one of those two parameters while keepeing the other equal, does not work as you would reduce or increase leverage.

    Next shock size is 50mm stroke in 190mm of total lenght.

    At 2.85 leverage that gives 144mm.... and you have a Reign!!!

    You see?? Leverage is very similar for both bikes... indicating that this is kind of a "sweet spot"... but either the Faith or Glory could send this argument to the recycle bin. The leverage on the Anthem is lower as the lowest shock stroke on the market is 1.5" and consequently, with only 3.5" of total travel, leverage should be around 2.3 in leverage.

    Now if you modify the rockers, the leverage will change and the sweet spot could be lost.
    If you put in a longer shock... you have a Reign and that's not exactly what you wanted and you have also to modify the rockers.

    It's catch 22.

    Also... the leverage thruough the travel variates depending on pivot location (read: rockers shape). And it heavily influences how the suspension controls anti-squat and braking forces.

    Try dropping a line to "_dw" on the IH forum... he's Dave Weagle himself and can throw in more light at it. Also, posting this question on the "Let's talk about shocks" forum would be good as there are serious suspension gurus in there (Seteve from JH, Derby, uktrailmonster, etc).

    Please don't forget to keep us posetd on how that turns out.... it's VERY interesting!!
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  13. #13
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    Quote Originally Posted by Warp2003
    You want 120mm rear travel, right?? (Who doesn't?? )

    Your shock now is a 38mm (1.5")stroke shock, that with a 2.85 ratio gives 108mm of total travel.

    To keep leverage equal, your one and only chance is to increse both shock and travel. Changing one of those two parameters while keepeing the other equal, does not work as you would reduce or increase leverage.

    Next shock size is 50mm stroke in 190mm of total lenght.

    At 2.85 leverage that gives 144mm.... and you have a Reign!!!

    You see?? Leverage is very similar for both bikes... indicating that this is kind of a "sweet spot"... but either the Faith or Glory could send this argument to the recycle bin. The leverage on the Anthem is lower as the lowest shock stroke on the market is 1.5" and consequently, with only 3.5" of total travel, leverage should be around 2.3 in leverage.

    Now if you modify the rockers, the leverage will change and the sweet spot could be lost.
    If you put in a longer shock... you have a Reign and that's not exactly what you wanted and you have also to modify the rockers.

    It's catch 22.

    Also... the leverage thruough the travel variates depending on pivot location (read: rockers shape). And it heavily influences how the suspension controls anti-squat and braking forces.

    Try dropping a line to "_dw" on the IH forum... he's Dave Weagle himself and can throw in more light at it. Also, posting this question on the "Let's talk about shocks" forum would be good as there are serious suspension gurus in there (Seteve from JH, Derby, uktrailmonster, etc).

    Please don't forget to keep us posetd on how that turns out.... it's VERY interesting!!
    seems that this was a missunderstandig as i'm german and english isn't my native language

    i should have written "angle and position of the linkage attached to the seattube" instead of "leverage position".
    I guess the position/angle of this linkage at the recommended sagpoint is very critical.
    My idea was to move the point where the damper is attached slightly to the main pivot point of the linkage plate.That would increase the transmission ratio to get more travel at the rear wheel.

    BTW, i did some measurements while removing the air completely from the damper.
    Maximum travel i got was 35mm damper/100mm rear wheel -> transmission ratio: 2,85
    Maximum travel i achieve in practice is about 32mm at the damper.So i'm running with 90mm travel. But it feels more like having 120mm compared to other suspension designs
    Last edited by zack; 10-13-2005 at 02:32 PM.

  14. #14
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    Quote Originally Posted by zack
    seems that this was a missunderstandig as i'm german and english isn't my native language

    i should have written "angle and position of the linkage attached to the seattube" instead of "leverage position".
    I guess the position/angle of this linkage at the recommended sagpoint is very critical.
    My idea was to move the point where the damper is attached slightly to the main pivot point of the linkage plate.That would increase the transmission ratio to get more travel at the rear wheel.

    BTW, i did some measurements while removing the air completely from the damper.
    Maximum travel i got was 35mm damper/100mm rear wheel -> transmission ratio: 2,85
    Maximum travel i achieve in practice is about 32mm at the damper.So i'm running with 90mm travel. But it feels more like having 120mm compared to other suspension designs
    Don't sweat the language stuff... I'm mexican so english is not my native language either.

    You're not accounting for a rubber bumper inside air shocks that is used to prevent destructive bottom out. So you might have some mm's left of travel. Please not that I'm considering your measurements are correct and I have no doubt of the leverage calculation you made. Looks spot on to me.

    Yes, what you wanted to do would increase your travel. That would rotate the upper link a bit counterclockwise (from crank side) and send the lower link dosnwards towards the bottom bracket shell.

    Note that when you restrain the movement of the lower link you can still move the swingarm. This actually happens deep into travel. If the lower link contacts the BB shell with your mod there is no problem as the swingarm will still rotate over the link... at the cost of affecting the wheelpath (not a good idea either).

    I know there are lots of drawbacks.... but if I were you and would have a lathe and the bike around, I would try it anyway.... who knows?? Maybe the mods give a better ride.

    Also, get the "Linkage 2" or 2.5 program for bike suspension analisys. What you want is to move the rockers without affecting the shock rate graphs.

    The leverage at each mm of travel changes depending on your pivots location... basically, with Maestro/DW you don't want to mess with this leverage graph.

    Not everything is lost and not everything is written... check thses two graphs... you can see the Ironhorse MkIII and the Reign 05 back to back... do you see how different shock leverages and wheelpaths are??? Maybe the change you're proposing gets you towards a more "MkIII-like" bike... and the MkIII is said to be a terrific bike.
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    Last edited by Warp; 10-13-2005 at 03:08 PM. Reason: changed plots... for correct ones
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  15. #15
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    Quote Originally Posted by Warp2003
    To keep leverage equal...

    ..Please don't forget to keep us posetd on how that turns out.... it's VERY interesting!!
    I find your insight very interesting. All this engineering behind these bikes is pretty intense. Maybe one day i will find myself doing stuff like that. I need to apply for post-secondary education soon
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  16. #16
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    Quote Originally Posted by rkj__
    I find your insight very interesting. All this engineering behind these bikes is pretty intense. Maybe one day i will find myself doing stuff like that. I need to apply for post-secondary education soon
    Dude... It helps to be a Mechanical Engineer

    But believe me... my knowledge about suspension is very, very LITTLE !!!!

    There are some real gurus out there. That's why I suggested to post this stuff on the shock forum as there are some really knowledgeable people there (I mentioned them earlier in this thread).

    Anyway, thanks for the compliment
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  17. #17
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    interesting graphics...
    Looking at the axle path of the Reign it seems to explain why i sometimes feel a very very little pedal kickback on my Trance going uphill.There is a range where the rear axle is constantly moving backwards. I guess the recommended sagpoint is somewhere at the turning point where the rear axle is changing to a forward movement.

    While googling for Linkage 2 or 2.5 i could not find a link to download or get some information. Warp2003 could you post a link to the program?

  18. #18
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    Quote Originally Posted by zack
    interesting graphics...
    Looking at the axle path of the Reign it seems to explain why i sometimes feel a very very little pedal kickback on my Trance going uphill.There is a range where the rear axle is constantly moving backwards. I guess the recommended sagpoint is somewhere at the turning point where the rear axle is changing to a forward movement.
    Actually, yes. You still want the rear wheel to move a bit rearwards and upwards over a bump, otherwise the wheel is resisting to roll over the obstacle

    Quote Originally Posted by zack
    While googling for Linkage 2 or 2.5 i could not find a link to download or get some information. Warp2003 could you post a link to the program?
    The official site is http://www.bikechecker.com/

    Let me swim a bit on my home computer and find out if I have still laying around the installation file for Linkage 2... I'll keep you posted.
    Last edited by Warp; 10-14-2005 at 05:42 AM. Reason: dumb mistake!!!
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    Warp2003, thanks for all your explanations! I have been working as i bike mechanic for 10 years, but that was 6 years ago. It seems that in the last years all the suspension design and damper technic has moved to a more sophisticated level.
    At that time in the bikeshop i allways tried a lot, made linkage plates to play with the suspension.
    Guess i will start again doing that stuff and see how it works.
    I'd love to have the Linkage program to get some more theoretical background.....

  20. #20
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    Quote Originally Posted by zack
    Warp2003, thanks for all your explanations! I have been working as i bike mechanic for 10 years, but that was 6 years ago. It seems that in the last years all the suspension design and damper technic has moved to a more sophisticated level.
    At that time in the bikeshop i allways tried a lot, made linkage plates to play with the suspension.
    Guess i will start again doing that stuff and see how it works.
    I'd love to have the Linkage program to get some more theoretical background.....
    You're welcome. There's nothing to thank, bro!!

    Send me a PM with your e - mail address... I found the installation file for Linkage. But it's the old version, unfortunately. Still, this is very good when trying to figure out how a suspension works.

    I'd like to have the 25 bucks to get the new version.... is so freaking sweet.

    If you send me you info today, you'll have it in your inbox by saturday early morning.

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    Edit---- I edited one of my posts below. The wheelpath has to go REARWARDS and upwards over a bump for the wheel not to fight the bump but rather roll over it. My mistake and was a very dumb one.
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    thats great, i will give you a PM soon.Thanks!
    you're speaking german, great where did you learn it?
    I noticed that with the FORWARD wheelpath. It did not make sense for me, REARWARDS makes more sense to catch the bumps

  22. #22
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    Quote Originally Posted by zack
    thats great, i will give you a PM soon.Thanks!
    you're speaking german, great where did you learn it?
    I noticed that with the FORWARD wheelpath. It did not make sense for me, REARWARDS makes more sense to catch the bumps
    I don't speak german... I worked with a couple german and swiss guys and two of my colleagues at school were grandsons of german people (surnamed "Jaeger")... but in my last post I spent 80% of all the words I know of german..

    I got your e-addy and as soon as I get home I'll send you the program.

    Godspeed on your return to bikes!
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    great, i'm looking forward to play with the program and see what happens when changing the transmission ratio of the Trance slightly.

    Looking at the axlepath of the reign the turning point of the graph is exactly where the recommended sagpoint is located (50mm travel).
    It seems that this is a critical point regarding chain tension interacting with the rear suspension...

  24. #24
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    Quote Originally Posted by zack
    great, i'm looking forward to play with the program and see what happens when changing the transmission ratio of the Trance slightly.

    Looking at the axlepath of the reign the turning point of the graph is exactly where the recommended sagpoint is located (50mm travel).
    It seems that this is a critical point regarding chain tension interacting with the rear suspension...
    Yes... for the Maestro/DW-Link allows for very little playing around.

    Check out http://www.dw-link.com/home.html

    It doesn't say much but it'll do good for learning more about these suspension schemes.

    Note that the leverage given in DW's page is taken inverse to what the Linkage program shows. While the DW page plot the ratio is 3:1 (rear wheel travel / shock stroke) the plot I posted from linkage (and any other plot generated by linkage) will show shock stroke / rear wheel travel. And as you will see, Dave Weagle is not lying. His bikes have a falling rate during the early to mid travel to have a ramp up at the end.

    With your mod, you want to have a similar leverage curve, otherwise you'll mess the suspension up.
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