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Finally got to ride with my subtanks

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I made my self some subtanks a few weeks back and haven't been able to ride til yesterday. Have to say this is the best mod I have ever done to a bike. I ride mostly woods and my forks just soak up all the sharp edge junk now. They were good before but amazing now. I run my compression at full soft for the woods and was thinking of softening up the valving but now I think I need to work on the shock a little first.

Here is a pic.

IMG_6536.jpg

-Lowedog

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How and what did you make those out of? About how much was your total cost? Please more info, I am very interested.

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Being a machinist has it's perks. :thumbsup: I machined the tank part out of white delrin plastic. The end caps are aluminum. The volume of each tank is 75cc. If a guy can find a cannister that is around that volume it would make for a real simple project. I think Air Cells uses a cannister made by Bimba. The fittings are simple to find. Do a google search for pneaumatic fittings and you will find all kinds of sources. I made a little fitting adapter to use the stock air bleed hole in my fork cap with the 90 deg instant fiitting. I didn't want to modify my fork caps. You could use a fitting with a 1/8 pipe thread and drill and tap your caps though. I used a valve on the tanks that meters the air in only and is free flowing out.

Total cost for the parts I used including the hose clamps is about $20.00. I have about 2hrs worth of work from design to finish.

-Lowedog

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I made my self some subtanks a few weeks back and haven't been able to ride til yesterday. Have to say this is the best mod I have ever done to a bike. I ride mostly woods and my forks just soak up all the sharp edge junk now. They were good before but amazing now. I run my compression at full soft for the woods and was thinking of softening up the valving but now I think I need to work on the shock a little first.

Here is a pic.

IMG_6536.jpg

-Lowedog

Very well done. :thumbsup: Do you have any means of controlling the rate in which air moves between the tank and fork chamber?

Sub tanks seem to open up a host of tuning possibilities. Even a tank with a diaphragm would seem to have some advantages.

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You could use a fitting with a 1/8 pipe thread and drill and tap your caps though.

Is there much of an advantage to running the 1/8 fittings? Just qiucker air flow I guess.

I used a valve on the tanks that meters the air in only and is free flowing out.

It is adjustable when the air leaves the forks to the tank right? Is there any reason to want to slow it down on its return?

This sounds like the mod for me since I ride woods but don't want to loose too much track-ability to the suspension. Seems to me you could back the subtank valve and fork clickers to full open on the slow woods runs, and tighten them in as needed for track riding. I want some. :thumbsup:

Oh yea, NICE WORK!! I like the look of those more than the stainless bimba tanks. :ride:

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The only thought on the 1/8 npt fittings is that you wouldn't need an adapter that would have to be custom made to fit up a fitting to your forks. It would also keep a lower profile to your fork cap.

The valve I used on the tanks only meters the air escaping the forks. I didn't see a need to control it going back to the fork. It can be adjusted anywhere from full open to full closed. I also used a straight fitting on the inside of the top cap with a piece of tube that goes to the bottom of the tanks to suck any oil back into the fork that might get pushed out.

These are great in the woods. What's really nice is it allows the air to escape into the tanks on all the small square edge stuff but when you hit some whoops or something big the air can't move fast enough so the fork acts just like it would without the tanks.

I have thought about a tank with a diaphram also. Seeing how the forks are not pressurized though I don't know that there would be an advantage over just having the air tanks.

-Lowedog

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Wow! Nice setup.

I want to do something similar, only I want to use my bars as the subtank. Has anyone thought of a way to put some kind of "wall" or block-off in the center of the inside of the bars, right between the bar clamps?

Anyone else using their bars as the tank? Any problem with fork oil getting in there and not getting back to the forks evenly?

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Being a machinist has it's perks. :thumbsup: I machined the tank part out of white delrin plastic. The end caps are aluminum. The volume of each tank is 75cc. If a guy can find a cannister that is around that volume it would make for a real simple project. I think Air Cells uses a cannister made by Bimba. The fittings are simple to find. Do a google search for pneaumatic fittings and you will find all kinds of sources. I made a little fitting adapter to use the stock air bleed hole in my fork cap with the 90 deg instant fiitting. I didn't want to modify my fork caps. You could use a fitting with a 1/8 pipe thread and drill and tap your caps though. I used a valve on the tanks that meters the air in only and is free flowing out.

Total cost for the parts I used including the hose clamps is about $20.00. I have about 2hrs worth of work from design to finish.

-Lowedog

You should market those, dude! You'd make a lot of money with that low overhead...

Nice job, btw!

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Does anyone know approximately how many psi are generated in these tanks? It sounds like 75cc is the volume to go with. Is there a reason for this volume or is it just to keep them compact? Last question-does the oil return tube at the bottom use the vacuum from the rebound stroke to suck it back into the fork?

Sorry for all the questions.

Thanks,

Paul

01' CR 250

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Does anyone know approximately how many psi are generated in these tanks? It sounds like 75cc is the volume to go with. Is there a reason for this volume or is it just to keep them compact? Last question-does the oil return tube at the bottom use the vacuum from the rebound stroke to suck it back into the fork?

Sorry for all the questions.

Thanks,

Paul

01' CR 250

On the twin chamber showa you dont need to worry about the fork pumping the chambers full of oil. They are vented through the inner chamber and it acts as a baffle preventing the oil transfer. The older style KYB accessed the bulk of the fork oil right at the vent so it'd push oil out.

Ive been running my own subtank setup for a couple years now. It works great. The tank is just a way to keep the system closed. I was talking to a guy that somebody thats offering something I knew would work. They vent the fork to the atmosphere via filters on the valves. The secret is in the valve, not the tank... :thumbsup:

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I was talking to a guy that somebody thats offering something I knew would work. They vent the fork to the atmosphere via filters on the valves. The secret is in the valve, not the tank... :thumbsup:

More info on that would be great!

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