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Author Topic:  IRC Bigbore shocks  (Read 2680 times)

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Offline badwobbleTopic starter

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IRC Bigbore shocks
« on: December 03, 2012, 12:36:47 PM »
What shock oil(weights) are you guys useing out there?
i have always used motor oil in my shocks..but have read i shouldnt do this with these shocks..is it something to do with the seals or the delrin ?
« Last Edit: December 03, 2012, 12:37:50 PM by neobaja »
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Offline Fifty8

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Re: IRC Bigbore shocks
« Reply #1 on: December 03, 2012, 05:42:53 PM »
I was using 500wt Venom silicon oil which which felt nice and smooth but not too firm.
I had a issue with punching the shock shafts through the piston on both rear big bore shocks.
When I rebuilt the shocks I choose 400wt silicon oil which is a bit softer and would be better suited to a rough and cut up SALS track.
I don't know the reason for not using motor oil in the shocks but i think you could be right with the motor oil affecting the seals or delrin

Offline badwobbleTopic starter

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Re: IRC Bigbore shocks
« Reply #2 on: December 03, 2012, 07:13:50 PM »
Thanks for that fifty8  thumbsup 

never heard about the bigbores busting pistons before,hope i dont have that problem..
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Offline Mr.Leopard

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Re: IRC Bigbore shocks
« Reply #3 on: December 03, 2012, 07:38:16 PM »
500Wt is pretty heavy...I use 500wt in the diff for the Baja !! Geebers

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Offline badwobbleTopic starter

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Re: IRC Bigbore shocks
« Reply #4 on: December 03, 2012, 08:10:05 PM »
I think its different readings for different brands,pretty sure fifty8 is saying 50wt down to 40wt
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Offline Fifty8

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Re: IRC Bigbore shocks
« Reply #5 on: December 03, 2012, 08:13:05 PM »
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500Wt is pretty heavy...I use 500wt in the diff for the Baja !! Geebers

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when I first got my big bore shocks for the baja I started off with a oil weight in the middle of IRC's oil weight recommendations for the rear shocks
 PSR worked it out to around 500wt silicon oil.
It felt quite good on the rear with all the extra upgraded weight it's carrying but I believed it to be a bit heavy for the SALS track.
I'm running 400wt at the moment but that maychange again with testing.

I believe Neo is correct from what I have been told.
have a look at this link,
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« Last Edit: December 03, 2012, 08:15:02 PM by Fifty8 »

Offline Fifty8

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Re: IRC Bigbore shocks
« Reply #6 on: December 03, 2012, 08:30:00 PM »
And to really confuse the oil weight subject
this has a lot more detail.
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Offline Crazy_stu

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Re: IRC Bigbore shocks
« Reply #7 on: December 03, 2012, 09:29:09 PM »
Always use pure silicone oil with the big bores otherwise the petroleum based oils will eat into your seals.

Im using HPI Pro Silicone oil in mine 30wt in the front and 40wt in the rear

Venom uses a different unit of measurment with there weights of oils, in saying that 500wt is not 50wt and so on.  Its really weird, venom is one of the only manufacturers that doesnt use the common unit of measurement so it makes it hard to know what your buying when you buy venom.
« Last Edit: December 03, 2012, 09:34:23 PM by Crazy_stu »
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Offline badwobbleTopic starter

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Re: IRC Bigbore shocks
« Reply #8 on: December 03, 2012, 10:21:57 PM »
Cheers Stu,i got a few different weights here so i might mix them up and get something that does a fare job..
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Offline klh mx10

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Re: IRC Bigbore shocks
« Reply #9 on: December 03, 2012, 11:57:25 PM »
Yep brand to brand is a PITA with weights and differences.

And I run anywhere from 1500-3000wt in my shocks using MCD or other silicone oils I have here, depends on the car and shock pistons, but most of my cars are heavy and on the dunes I run really heavy oils to keep the cars flat off jumps and to take the big hits,  and for my whooped sand tracks here a slower suspension action works well to stop the rear pogoing everywhere, my set up is totally different I'd say to you East Coasters running on hard packed clay etc where a soft supple suspension action would keep the wheels tracking on the ground.
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Offline Mr.Leopard

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Re: Re: IRC Bigbore shocks
« Reply #10 on: December 04, 2012, 12:15:51 PM »
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Always use pure silicone oil with the big bores otherwise the petroleum based oils will eat into your seals.

Im using HPI Pro Silicone oil in mine 30wt in the front and 40wt in the rear

Venom uses a different unit of measurment with there weights of oils, in saying that 500wt is not 50wt and so on.  Its really weird, venom is one of the only manufacturers that doesnt use the common unit of measurement so it makes it hard to know what your buying when you buy venom.
Mcd fg and harm all use different to the standard measurement aswell

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Offline badwobbleTopic starter

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Re: IRC Bigbore shocks
« Reply #11 on: December 03, 2013, 12:25:59 PM »
Still going strong headbang  running 40wt F/R have busted one front piston and 2 lower ball ends(replaced with FG ones )  otherwise these shocks are simply awesome.
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Re: IRC Bigbore shocks
« Reply #12 on: December 03, 2013, 12:36:36 PM »
Same here Brett, got them on the heavy twin and the only thing i have busted was the rod ends, no leaks either headbang
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Re: IRC Bigbore shocks
« Reply #13 on: June 11, 2019, 07:09:06 PM »
Love you BW.
What balls go in the FG shock ends when running on IRC Baja?
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