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Fork & Shock Upgrade
Got a 2012 Giant Trance, pretty happy with it all round, but even with my 65Kg frame and limited skillz, I seem to be hammering the suspension despite running much higher pressures than i should for my weight. Also wouldn't mind some extra travel on the front.
So I'm considering upgrading both, I just need some advice/abuse on what will and won't work.
Forks:
Have:
Fox FLOAT 120 RL FIT Performance w/ 15QR axle and OverDrive 2 Steerer, 5”/120mm Travel, 1 1/4"-1 1/2"
Want:
Fox 34 TALAS 160 FIT CTD w/Trail Adjust. 120-160mm travel.
http://www.foxracingshox.com/product.php?m=bike&...
Now I'm assuming the overall height of both would be the same (ignoring talas) so it won't mess up anything, and Fox don't actually list the length of any fork. So a straight swap should be fine?
Shock:
Have:
Fox Factory RP23 w/XV sleeve, Boost valve &Adaptive Logic
Want:
FLOAT CTD Boost Valve w/Trail Adjust
http://www.foxracingshox.com/product.php?m=bike&...
Apparently i need a 'high volume' version, but again, i assume i just match the length/travel and it should be fine?
Any advice/comments appreciated. Thanks.
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I think you'll find the A to C lengh of the 160mm much longer than the 120mm. Your Trance would resemble a chopper!
You could go up to a 140mm fork, in fact I have a 140mm TALAS fork I'm considering putting on my wife's Trance but would not go any longer. You risk fatiguing the head tube running it too slack with too long a fork.
Running more pressure than suggested is not really an issue - as long as the sag is around 20-30% and you're not regularly bottoming out. When you say hammering, do you mean bottoming out?
RP23 is a good shock. What exactly is your problem with it. I've got a RP23 on my Remedy, had one on my Fisher and know lots of others with them. My only issue with it is that being 95kg I need to run it a bit hard to stop it from bottoming out but it rides sweet.
I guess I haven't really helped you too much but a bit more info on what issues you have with the current set up will help others give good advice.
+1 to BLKFOZ. If you exceed the manufacturer's recommended axle-to-crown height you risk folding the frame behind the steerer and that will not end well.
Perhaps an upgrade to a Giant Reign (150mm travel) would be a better solution. A mate of mine has one and with the dropper seatpost it sounds like the right kind of bike for what you're doing.
It's a bit burlier as well so will survive the treatment you're giving your steed much better.
The 1-1/4in steerer that Giant uses could prove a bit difficult too with an aftermarket fork. Not saying you won't get one but it won't be something that you would normally find sitting on the shelf of a LBS or online store.
I would say your setup is more the issue than the components and you may only need to get a damper tune from Tekin or NS Dynamics on both to fix the problem.
Not only you will put more strain on the frame than it is de3signed to, but anything over 140mm will void warranty.
If you are bottoming both ends out regularly, what you may try for free is to add a little more oil to the air chamber on both fork and shock (very easy to do) to reduce volume and increase the ramp up towards the end of the stroke.
Thanks guys.
The RP23 is decent enough, but i figured since id be replacing the fork (my main gripe), may as well do both.
When i say hammering, I can't actually feel any bottoming out, but i certainly use every bit of travel on both ends.
When i sit on the bike, the forks will sag maybe 0-10mm (so certainly on the hard end). Shock is pumped up to max (300psi???), sag is maybe 10-20mm. Again, both of them push the o-rings to what i assume is the limit after just one landing.
Putting a little extra oil in is certainly something easy i can try first. Thanks.
Considered another bike, but i only just got this one in feb after my 1st hard tail. Got it setup nicely too with a drop seat post, carbon riser bars and some subtle bling-bling.
A Reign would be good if they made carbon, what id really like is a Remedy... just waiting for that lotto money to come in
Anyway, i guess I really just need to find one of these shocks and measure the bloody thing myself. If i can only use a 140, i probably won't bother.
Thanks again for the help.
Ok... i think I've cracked this...
Scoured the Fox website after a tip from MTBR, and finally found the full specs.
32x120mm travel is 491mm axle to crown
34x160mm is 545mm
A difference of 47mm height.
Now the model up from mine, the SL, runs a 140mm fork, which is 27mm higher.
According to all the frame angles and sizes, the frames are identical, which should mean that if Giant are happy to put a 140mm fork on SL, i could put on a 160, and since both frames are the same....
Also checked fork angles:
SL @ 140mm = 69.5
Adv @ 120 = 70.5
Without cracking open my high school G&T books, the head angle of a 160mm on my bike will not exceed 68.5 And when i say exceed, i mean it won't be less
To give a comparison the Reign runs at 67.5, and the Glory 65.5
In addition to that, with more travel i can actually have some sag on the fork, which means handling should be identical.
Maybe also use a fatter tyre on the back, but with a 1 degree difference over the SL, and 2 degrees over what Its currently, i don't think it will be an issue.
Or is that just wishful thinking?
The next thing is the steerer... guess I'll go to my LBS.
After that, the handlebars will obviously be close to 47mm higher, but I can always ditch the 35mm riser bars and or remove a spacer. If i even notice.
I'm not sure if you will need new forks to get more travel, I have a set of fox 32 rlc on my bike and the fox manual shows that i can remove a spacer from the inside to increase my 120 travel to 140 travel so it would pay to check if your forks have the same option.
g'day, you are still exceeding the spec by 20mm - just a cursory glance at a reign will tell you the tube and weld thickness is greater on the headtube than the trance.
I dont believe what you are proposing will improve the trance in any signifcant way, but its going to cost well north of a grand. For a grand you would be able to sell yours and get a brand new reign pretty much. Its a lot of cash for very small benefit - why not just get the frame with the slacker angle and more travel in the first place?
MrMez said "I can't actually feel any bottoming out, but i certainly use every bit of travel on both ends"
Sounds like you have it pretty well dialed, after all the travel is there to be used, and most forks have a hell of a time being supple over trail chatter, stiff under pedalling and still accessing all the travel.....
+1 for a possible custom damper tune though. The RLC fork allows the rider to adjust Hi and Lo speed compression damping, which can help balance the forks characteristics to suit rider style and weight... your RL is restricted to a fixed compression damping curve.
Are you sure about that?
At only 65kg I'm surprised you're getting any sag at all.
I'd be consulting your local bike shop for advice. If what you're saying is correct(and I'm not doubting you)there may be something wrong with either the shock itself or the set up.
If they're anywhere near responsible they'll be advising against what you're proposing.
Good luck.
is it a trance or trance x that you have?i think the top of the line trance x,2010/2011 came with a talas 140mm, check that the fork dropouts match your front hub too,changing your stem to a slightly shorter one and going a little wider in your bar width can increase the handling too,making it more stable and fun in the rough,stock setups are rarely as much fun,the more diverse your setup, the more the fun, go for it matey
is it a trance or trance x that you have?i think the top of the line trance x,2010/2011 came with a talas 140mm, check that the fork dropouts match your front hub too,changing your stem to a slightly shorter one and going a little wider in your bar width can increase the handling too,making it more stable and fun in the rough,stock setups are rarely as much fun,the more diverse your setup, the more the fun, go for it matey
MrMez go for the 160 forks. You will like the extra travel which will add stability at speed and add a touch of playfullness that you wont regret.
It will give a more relaxed feel to your riding style and add confidence in railing bermed corners.
I believe the frame will handle it, unless your a big harsh hitter on jumps n drops, in which case you would be looking at a more durable frame.
Longer travel at the front with a tighter rear travel is a fun playful bike to suit WA trails.
Go for it.
Not sure if we read the same first post?
He is running quite high pressures / low sag levels for his weight and is complaining about blowing through the travel too easily... and using the full travel on a Fox fork is no mean feat given the way they ramp up at the end.
It's my view he should "be looking at a more durable frame". Trading up to a Reign is more cost effective on so many fronts, and the geometry is better suited to more aggressive and technical all-mountain riding
I totally agree hawkeye.
Putting 160mm travel forks on a trance is silly. It would change the geo and be all wrong.
I own a Trance and Reign and might bottom my suspension once or twice a ride which is spot on. I weigh 84kgs and dont run anywhere near the pressurs the OP is talking about.
I the OP should focus on bike handling skills first before wasting money on new suspension.
Shock is pumped up to max (300psi???), sag is maybe 10-20mm.
I am 85klg Trancex1 rider running 200psi, 12mm sag. i think you should get LBS to check rear shock setup.
the OP could maybe try a different shock pump...or different pumping technique... maybe his gauge is all screwed up as he seems to be running extremely high pressures both ends?
The RavX shock pump I had originally had a small screw in valve depresser. If that was neglected then the pump reading was way over the chamber reading as the valve never allowed pressure equalisation. Similar deal as pumping up through a Presta valve on a 23mm tyre. If I don't tickle the valve before putting the pump head on it'll take about 180 psi to crack it open.
Just a thought.
Thanks again for the input.
Over the weekend did some testing, including filming both ends at 100fps.
First I let all the air out and found that I wasn't using all of the travel on either. Ended up being ~10-20mm off which is probably a pretty good setup and why I couldn't tell if I was bottoming out.
What I found:
-Softening up both ends did make a noticeable improvement and feel and I also seemed to be launching off jumps perfectly level every time. Watching the video after and looking at the o-rings I was bottoming out on just about every landing.
-At ~200psi on the rear on soft setting I can just about hit bottom bunny hopping in the driveway.
-50psi in the front feels great but will bottom out several times on a medium run at Kamikaze. Of all the comparisons I did, this run is toughest on the front.
Guess I've got more testing to do next week. I'll take my shock pump with and do 3 or 4 runs through Kamakazi and see what happens.
I'll also post some vids tomorrow, but not at 100 fps