sub tanks and a 426


14 replies to this topic
  • GONE1445

Posted November 18, 2006 - 02:24 PM

#1

ok I got the correct springs for my 426 for my weight and it doesn't bottom on the few small jumps I hit anymore :cheers: they where all flat landings to by the way

my question is should I get some sub-tanks for the ol 426 also I plan on putting in new seals and fresh oil this winter and figured why not put some sub tanks on while I am at it

this is my understanding on what the sub tanks do, you can run higher oil without the suspension getting harsh, so you get plush suspension and greater bottoming resistance basically the best of both worlds

is this correct

the sub tanks I was looking at where by tech-care http://www.tech-care.com/

if you think I should run them what oil height should I run and also what kind of fork oil weight is stock in the 426 2001 or what weight should I get I am a big boy at 285 so I was thinking of getting a higher weight oil to help with bottoming

  • grayracer513

Posted November 18, 2006 - 02:51 PM

#2

Sub tanks work well on the early KYB's, but they should be re-valved for their use to get the most out of them.

The problem was that if the oil level was lowered to allow a plush ride over the little stuff (slow speed compression), they bottomed on the big stuff (high speed), and worse, they were so low at that point that they worked foam into the oil and faded. If the oil was high enough to stop that from happening, the fork became intolerably harsh. The answer was to increase the air capacity with an added tank. This, in one way of looking at it, decreased the "compression ratio" of the fork. That let the rider run a higher oil level to avoid bottoming and foaming without raising the internal air pressure so high that it caused harshness. Adding the metered air flow feature later provided the rider a way to run even softer compression damping because it made the air spring component speed sensitive.

  • yz_for_me

Posted November 18, 2006 - 06:00 PM

#3

I've used them (home made, see my garage) on my 426 with great success. Like grey said you will get the most improvement if you revalve, but you will still see noticable improvment even without a revalve.

I ran mine with the max recomended oil height. At that level, if I ran the tank valves fully closed, the forks were pretty harsh so I normally ran them open about 1/2 to 3/4 turn for moto. On the other hand if I ran the valves fully open the forks were way to soft for moto but very good for off road and trails. This arrangement was great for dialing in the plushness for a wide variaty of terrain.

  • GONE1445

Posted November 18, 2006 - 07:29 PM

#4

what did you use to make those

and how??

  • grayracer513

Posted November 18, 2006 - 07:42 PM

#5

I used a single tank configuration

  • yz_for_me

Posted November 20, 2006 - 04:45 PM

#6

what did you use to make those

and how??


In my case I used a two tank system. A one tank system is simpler and less expensive, and has the added benefit of being self draining. I went with a two tank set up because at the time I built mine there was a lot of talk about a single tank system not draining equally into both forks. This would eventually result in uneven oil levels in your forks. I don't know if that's really a problem. It seems like a lot of people use a one tank system without any trouble. If I was doing it again I'd probably go the one tank route.

In any case here's what I used. The tanks are Bimba air reserviors and the valves I used are Bimba one-way flow controls. The tanks come tapped for 1/8 NPT fittings. I drilled and tapped my fork bleeder holes out to 1/8 NPT also. The braided hoses can be purchased at any paintball store or can be custom made. I designed and fabbed the brackets using carbon fiber plates to hold the tanks, but any number of methods will work. I've seen people just zip tie them to the forks. Simple but effective.

Here's a list of part numbers I used.
Tanks:
1.25 Diameter x 3.00 long. The Bimba part number is D-27715-A-3. They list for about $17.00 each
Valves:
Bimba part number FCP2L and list for about $13.00 each

One word of advice, when using valves like these, make sure they only restrict airflow in one direction. When you set up the system, make sure the valves are installed to restrict airflow OUT of the fork.

Hope this helps.

  • Matt96xr6

Posted November 20, 2006 - 08:34 PM

#7

I had the subtanks on my 426 and they helped. But removed them after installing goldvalves in the forks and spent some time revalving them to my liking.

I like the goldvalves way better than the subtanks with stock valving.

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  • GONE1445

Posted November 20, 2006 - 11:00 PM

#8

thanx guys

right now the forks feel pretty good as far as not being too harsh but I hit a couple jumps by my house(flat landings) and it got close to bottming so I wanted to get some better bottoming resistance

maybe I will get them valved next summer

  • christoswr

Posted January 21, 2007 - 01:04 PM

#9

In my case I used a two tank system. A one tank system is simpler and less expensive, and has the added benefit of being self draining. I went with a two tank set up because at the time I built mine there was a lot of talk about a single tank system not draining equally into both forks. This would eventually result in uneven oil levels in your forks. I don't know if that's really a problem. It seems like a lot of people use a one tank system without any trouble. If I was doing it again I'd probably go the one tank route.

In any case here's what I used. The tanks are Bimba air reserviors and the valves I used are Bimba one-way flow controls. The tanks come tapped for 1/8 NPT fittings. I drilled and tapped my fork bleeder holes out to 1/8 NPT also. The braided hoses can be purchased at any paintball store or can be custom made. I designed and fabbed the brackets using carbon fiber plates to hold the tanks, but any number of methods will work. I've seen people just zip tie them to the forks. Simple but effective.

Here's a list of part numbers I used.
Tanks:
1.25 Diameter x 3.00 long. The Bimba part number is D-27715-A-3. They list for about $17.00 each
Valves:
Bimba part number FCP2L and list for about $13.00 each

One word of advice, when using valves like these, make sure they only restrict airflow in one direction. When you set up the system, make sure the valves are installed to restrict airflow OUT of the fork.

Hope this helps.


Is there a way i can make my own subtanks with the parts you mentioned without drilling the forks?

  • jocolo

Posted July 08, 2008 - 06:42 PM

#10

any one knows where can I order this parts from Thanks

  • jocolo

Posted July 08, 2008 - 06:42 PM

#11

sorry to bring this up

  • grayracer513

Posted July 08, 2008 - 06:56 PM

#12

Order from the manufacturer. See my post farther up.

  • jocolo

Posted July 08, 2008 - 09:03 PM

#13

I just couldnt find the tanks in their catalog

  • grayracer513

Posted July 08, 2008 - 09:37 PM

#14

E-mail them and ask for the air reservoir by the part number I listed.

  • jocolo

Posted July 09, 2008 - 06:15 AM

#15

anyone knows the outer diameter of the aircell's tubing size? they sell the fork cap fitting, wont have to tap them





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