Difference between PSI and POUNDS?
#1
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Pain Cleanseth

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Difference between PSI and POUNDS?
Please help me clarify something. I am being told that I am putting to much pressure in my shock. The manual calls for 52lbs, so I am putting 52psi(based on my shock pump) into my MX Comp Pro. I am trying to explain that there is no difference between the two. Please correct me if I am wrong.
#2
THIS BIKE'S 4 U !!!!
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From: Western, NC .... (Pisgah, Bent Creek, DuPont)
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You are correct. There are two (2) different types of valve systems on the forks we all have nowadays. Low pressure (PSI) & high pressure (PSI). Yours is apparently one of the "high" pressure systems....
Mine calls for about 25 psi.
Mine calls for about 25 psi.
#3
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Pain Cleanseth

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Originally Posted by Killer B
You are correct. There are two (2) different types of valve systems on the forks we all have nowadays. Low pressure (PSI) & high pressure (PSI). Yours is apparently one of the "high" pressure systems....
Mine calls for about 25 psi.
Mine calls for about 25 psi.
#4
THIS BIKE'S 4 U !!!!
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From: Western, NC .... (Pisgah, Bent Creek, DuPont)
Bikes: HARO Xtreme X2, K2 Lithium 3.0, K2 Beast, K2 Flyin' Monkey, DiamondBack Accent EX, DiamondBack Axis TR
Who cares what anyone else tells you.... I sure don't....
Just do as the manual instructs.
Good Luck!
Just do as the manual instructs.
Good Luck!
#5
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Pain Cleanseth

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Originally Posted by Killer B
Who cares what anyone else tells you.... I sure don't....
Just do as the manual instructs.
Good Luck!
Just do as the manual instructs.
Good Luck!
#7
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From: CO Springs, CO
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What shane is trying to say - I think - is that to put 45-52 pounds of weight on your handlebars your shock needs the 0-15 PSI (what we commonly refer to as pounds for short).
Of course, I may be wrong.
Some shocks do have high pressures; my Fox Float runs about 100 psi for my weight.
Of course, I may be wrong.
Some shocks do have high pressures; my Fox Float runs about 100 psi for my weight.
#9
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Pain Cleanseth

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Originally Posted by dirtyamerican
Or just replace your MX comp pro with a better fork.
I bought what I could. Some people can't afford the best. Thanks for the kind words.
#11
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According to the chart, you need about 50psi. I've got a Manitou fork that runs more than 2x that, along with a Fox Float shock. Some systems use low pressure, some use high. How does the fork feel at that much pressure?
#12
Originally Posted by Feltup
Please help me clarify something. I am being told that I am putting to much pressure in my shock. The manual calls for 52lbs, so I am putting 52psi(based on my shock pump) into my MX Comp Pro. I am trying to explain that there is no difference between the two. Please correct me if I am wrong.
Your manual calls for a pressure of 52lbs, but this is probably just the manual writer being lazy, or inaccurate, in the units being used. The number is probably correct (I don't know your fork) but the pressure should almost certainly be 52 PSI. So you have been using the correct pressure.
#13
Ouch!!!
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Originally Posted by skiahh
What shane is trying to say - I think - is that to put 45-52 pounds of weight on your handlebars your shock needs the 0-15 PSI (what we commonly refer to as pounds for short).
Of course, I may be wrong.
Of course, I may be wrong.
As I tried to explain, the 'Zocchi manual shows two different lines - one shows weight measured in POUNDS (weight on the bars - NOT PSI), vs. preload air pressure (measured in PSI - pounds per square inch).
Again, you add 0 - 15 PSI to achieve a sag of 20 - 25% of total available travel. The MX COMP series that started all this, only has one air valve. Maybe someone would like to tell me why the manual shows 0-15 PSI of preload, and 30 - 65 pounds positive air? It can't be both.....there's only one air valve on the Comp.
Again, adding 0 - 15 PSI gives you 30 - 65 pounds of positive air.
Last edited by shane45; 10-22-05 at 05:26 AM.
#15
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Pain Cleanseth

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Originally Posted by shane45
Not wrong - thank you.
As I tried to explain, the 'Zocchi manual shows two different lines - one shows weight measured in POUNDS (weight on the bars - NOT PSI), vs. preload air pressure (measured in PSI - pounds per square inch).
Again, you add 0 - 15 PSI to achieve a sag of 20 - 25% of total available travel. The MX COMP series that started all this, only has one air valve. Maybe someone would like to tell me why the manual shows 0-15 PSI of preload, and 30 - 65 pounds positive air? It can't be both.....there's only one air valve on the Comp.
Again, adding 0 - 15 PSI gives you 30 - 65 pounds of positive air.
As I tried to explain, the 'Zocchi manual shows two different lines - one shows weight measured in POUNDS (weight on the bars - NOT PSI), vs. preload air pressure (measured in PSI - pounds per square inch).
Again, you add 0 - 15 PSI to achieve a sag of 20 - 25% of total available travel. The MX COMP series that started all this, only has one air valve. Maybe someone would like to tell me why the manual shows 0-15 PSI of preload, and 30 - 65 pounds positive air? It can't be both.....there's only one air valve on the Comp.
Again, adding 0 - 15 PSI gives you 30 - 65 pounds of positive air.
#16
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Pain Cleanseth

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Originally Posted by iamthetas
whats wrong with the MX comp? mine does me just fine
#17
Originally Posted by Feltup
NOOOOOO positive air...................forget it your to thick headed to see.
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#18
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Originally Posted by Feltup
There is nothing wrong with your fork. The MX comp is made for a certain kind of riding and it is not the kind that dirtyamerican does, so it is junk to him. The MX comp series has great reviews and preforms great on the trail. It might not be able to take huge drops but you don't do huge drops on a XC bike.
this fork seems better at the big hits than the small ones for me. Im 200 pounds plus gear and run at 40 PSI
#19
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Originally Posted by shane45
Not wrong - thank you.
As I tried to explain, the 'Zocchi manual shows two different lines - one shows weight measured in POUNDS (weight on the bars - NOT PSI), vs. preload air pressure (measured in PSI - pounds per square inch).
Again, you add 0 - 15 PSI to achieve a sag of 20 - 25% of total available travel. The MX COMP series that started all this, only has one air valve. Maybe someone would like to tell me why the manual shows 0-15 PSI of preload, and 30 - 65 pounds positive air? It can't be both.....there's only one air valve on the Comp.
Again, adding 0 - 15 PSI gives you 30 - 65 pounds of positive air.
As I tried to explain, the 'Zocchi manual shows two different lines - one shows weight measured in POUNDS (weight on the bars - NOT PSI), vs. preload air pressure (measured in PSI - pounds per square inch).
Again, you add 0 - 15 PSI to achieve a sag of 20 - 25% of total available travel. The MX COMP series that started all this, only has one air valve. Maybe someone would like to tell me why the manual shows 0-15 PSI of preload, and 30 - 65 pounds positive air? It can't be both.....there's only one air valve on the Comp.
Again, adding 0 - 15 PSI gives you 30 - 65 pounds of positive air.
#21
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Pain Cleanseth

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Originally Posted by thumbnut
I do believe the 0-15# thing is for the MX COMP ETA spring fork. The 30-60# is for the air sprung MX COMP, no ETA fork. Went through this same thing when I got my MX PRO ETA fork. The manual sucks.





