First day out, now to re-tune the suspension

Apr 16, 2018
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Australia
#1
What an awesome first ride, loving the bike! Suspension setup done by the shop not so much. I found the shock basic setup in the manual but nothing about the fork.
Whats the sag meant to be and roughly what pressure as a baseline.?

superscreenshot-2018-5-16-18-7-35-png.1499


Cheers
 

Ryder

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Apr 24, 2018
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#3
Fork is about 20% of total travel. What are you not liking about the setup at the moment?
 

R120

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Apr 13, 2018
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#4
There is a bit of conflicting information on sag with e-bikes. Giant recommend 25% on their E-Bikes, and i have seen others say 20% to take into account the extra weight, i have my analogue endure set up at around 30% and my e-bike at closer to 20%
 
Apr 16, 2018
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18
Australia
#5
Fork is about 20% of total travel. What are you not liking about the setup at the moment?
It’s really harsh, on the big bumps it’s ok on smaller-medium stuff it hard and bounces you everywhere. I’d guess need to back off the compression but figure it’s best to start from scratch
 

kcarbon

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#7
It’s really harsh, on the big bumps it’s ok on smaller-medium stuff it hard and bounces you everywhere. I’d guess need to back off the compression but figure it’s best to start from scratch
STU - K , I had same problem ( harsh ride ). my shop set it to the info they have.
but on hard down hill with lot of rocks & bumps, my front wheel seemed to be bouncing. so back to LBS they seemed to be worried if set softer it would bottom out. but I just kept going back asking to take 10psi out at a time, then testing, till it was good now I love it, I fly down the roughest hills, also this is my second levo, first was 2016 HT fatty. that had 27.5 X 3.0" tyres stock, these tyres low pressure with a maximum pressure of 20 p.s.i , then traded it on the one I have now FSR levo, that came with 27.5 X 2.8" tyres. I noticed they did not roll as well and felt harder. so got a set of the low pressure 27.5 X 3.0" tubeless I run 12 p.s.i front , 15 p.s.i rear. love it smooth ride!!
you might need a different setting to me as we all come in different sizes. but how I look at it is, just because I weigh so & so, does not mean that total weight will be on the front, I think the rear takes more weight.
I'm not racing so don't need real fine tuning, but I ride with a group that ride at a fast speed in the dirt and some technical single track.
 
Apr 16, 2018
37
6
18
Australia
#8
STU - K , I had same problem ( harsh ride ). my shop set it to the info they have.
but on hard down hill with lot of rocks & bumps, my front wheel seemed to be bouncing. so back to LBS they seemed to be worried if set softer it would bottom out. but I just kept going back asking to take 10psi out at a time, then testing, till it was good now I love it, I fly down the roughest hills, also this is my second levo, first was 2016 HT fatty. that had 27.5 X 3.0" tyres stock, these tyres low pressure with a maximum pressure of 20 p.s.i , then traded it on the one I have now FSR levo, that came with 27.5 X 2.8" tyres. I noticed they did not roll as well and felt harder. so got a set of the low pressure 27.5 X 3.0" tubeless I run 12 p.s.i front , 15 p.s.i rear. love it smooth ride!!
you might need a different setting to me as we all come in different sizes. but how I look at it is, just because I weigh so & so, does not mean that total weight will be on the front, I think the rear takes more weight.
I'm not racing so don't need real fine tuning, but I ride with a group that ride at a fast speed in the dirt and some technical single track.
What sort of PSI are you running in the forks now and how much do you weigh? I have the 2.8 butchers running 30 psi by the shop setup. Just ordered a 600 psi shock pump as I’m sure the shop only had a 300 and that’s not enough for shock setup
 

kcarbon

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#9
What sort of PSI are you running in the forks now and how much do you weigh? I have the 2.8 butchers running 30 psi by the shop setup. Just ordered a 600 psi shock pump as I’m sure the shop only had a 300 and that’s not enough for shock setup
Stu I weigh 75kg 30 psi in the butcher sounds high to me.
my bike is the 2018 Comp carbon if that means anything Rock Shock front & rear, I think they started out with 110 p.s.i air spring pressure in forks, was way too hard. now have 30 p.s.i in forks.
in front tyre 2.8" butcher I would run 20 p.s.i & 22p.s.i rear 30 p.s.i sounds too high to me. but the 2.8" butcher do run at higher pressure than the Purgatory 3.0" I like the 3.0 better myself . but everyone different
 

knut7

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Apr 10, 2018
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#10
What sort of PSI are you running in the forks now and how much do you weigh? I have the 2.8 butchers running 30 psi by the shop setup. Just ordered a 600 psi shock pump as I’m sure the shop only had a 300 and that’s not enough for shock setup
Hmm, the shocks usually don't like to go way above 300psi. In some cases it could be necessary, but usually not. Could there be too much air pressure in the negative chamber? Try letting out most of the air and comress the shock a few times, that may equalize the chambers. Or try suggesting it to your LBS.

Most bikes come with high air pressure in the tyres it seems. I'm pretty sure 30psi is too high.

There are two ways of measuring fork sag, standing up or seated. I prefer standing up and usually aim for 25%.
 
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Apr 16, 2018
37
6
18
Australia
#11
Stu I weigh 75kg 30 psi in the butcher sounds high to me.
my bike is the 2018 Comp carbon if that means anything Rock Shock front & rear, I think they started out with 110 p.s.i air spring pressure in forks, was way too hard. now have 30 p.s.i in forks.
in front tyre 2.8" butcher I would run 20 p.s.i & 22p.s.i rear 30 p.s.i sounds too high to me. but the 2.8" butcher do run at higher pressure than the Purgatory 3.0" I like the 3.0 better myself . but everyone different
Yeah I’m 105kg so guess I’m a bit outside the normal setup, LBS said anything above 95kg is the same setup in their book,wtf?!

Set up a few motorbikes dirt and road over the years how much different could it be 😁
 
Apr 16, 2018
37
6
18
Australia
#12
Hmm, the shocks usually don't like to go way above 300psi. In some cases it could be necessary, but usually not. Could there be too much air pressure in the negative chamber? Try letting out most of the air and comress the shock a few times, that may equalize the chambers. Or try suggesting it to your LBS.

Most bikes come with high air pressure in the tyres it seems. I'm pretty sure 30psi is way to high.

There are two ways of measuring fork sag, standing up or seated. I prefer standing up and usually aim for 25%.
According to manual, pump shock to body weight (kg) x 3. For me 315psi( max 350psi)then sit on bike and hold down auto sag valve til no more air comes out.
On tyre side wall it says something like 35-60 psi.
It’s all new to me as my last bike was setup by a shop that seemed to nail it so I never touched it. 🤔
 

kcarbon

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#13
Yeah I’m 105kg so guess I’m a bit outside the normal setup, LBS said anything above 95kg is the same setup in their book,wtf?!

Set up a few motorbikes dirt and road over the years how much different could it be 😁
Stu , i ride motor bikes too.
I think I would look for another specilized shop not too far for second oppinion
.
 

Ryder

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Apr 24, 2018
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#14
Stu, try slower rebound settings if it is bouncing you around a lot that may help
 

kcarbon

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#15
Stu , Ryder is spot on ! I had forgotten, when mine was bouncing, they told me try to slow rebound, there is a tortoise & a rabbit, so turn to the slow & steady. that helped me a lot.
 

Theolegit

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#16
Stu , Ryder is spot on ! I had forgotten, when mine was bouncing, they told me try to slow rebound, there is a tortoise & a rabbit, so turn to the slow & steady. that helped me a lot.
At 105kg Rockshox recommend 2 clicks on the rebound from the slowest setting
 

knut7

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Apr 10, 2018
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#17
According to manual, pump shock to body weight (kg) x 3. For me 315psi( max 350psi)then sit on bike and hold down auto sag valve til no more air comes out.
On tyre side wall it says something like 35-60 psi.
It’s all new to me as my last bike was setup by a shop that seemed to nail it so I never touched it. 🤔
People with moto background tend to be good at setting up (e)bikes too. 315psi isn't insanely high, I take it no air comes out with the autosag using your current pump...

If your bouncing around on the smaller stuff then more rebound could do the trick, as already suggested. But also tyre pressure can cause this. Don't mind the print on the tyre. You can reduce tyre pressure until the sidewalls get unstable. And you need enough air pressure to avoid rim strikes. Then you can experiment a bit with air pressure levels above that to find out what gives the best ride.
 

kcarbon

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Feb 3, 2018
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#18
all I can say is, 110 pound in air spring to support 75kg + small amount of gear, was far too hard and was getting no where close to the 150mm travel. even if I did a jump it would not have been close to full travel. it was as bad almost as riding my skinny tyre road race bike down a rough dirt track, steep incline.
I backed the adjustment back to slowest rebound. had LBS back off air spring pressure in 10p.s.i lots ( would go for a hard ride down same rough hill as its one of roughest I come across ) now finally ok I can go as fast down hill as the fast riders in my group & have control. but its no where near as good as a MX motor Bike, I don't think air spring could match coil spring & damping. but air lighter. anyway I'm at 30p.s.i in the air spring now and have never came close to bottoming out so double 75kg = 150kg , double 30p.s.i -= 60p.s.i and a long way from 300p.s.i
try slowing your rebound & take 10 p.s.i at a time out.
when you get it close you will love it! also my LBS Ladies said they will do some in depth fork setting they found out from some Guru. so next 1,000km will drop her off. hope we are using the same forks? mine rock shock 34 cheers
 

kcarbon

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#20
no worries hope info I gave helps, enjoy it! love mine.
 
Apr 16, 2018
37
6
18
Australia
#23
Interestingly the manual says for autosag setup inflate rear shock to 3 x kg body weight( for me 105kg x 3= 315psi)with a max of 350 psi. Written on shock do not inflate over 275 psi.
 
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