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Subtanks Questions

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Been reading some threads on TT about some who have fabricated their

own subtanks. I have a couple general questions about how they work.

1) They talk about using a flow control valve coming out of the fork.

It's supposed to be somewhat limiting on the out flow and zero limiting the

flow back in. How much limiting on the out flow? 30%? 50%?

They said some valves are adjustable. Fixed or adjustable I'd need to

know approx.what the flow needs to be, then I'll have some research/

shopping to do @ Grainger, McMaster Carr or somewhere similar.

2) How much pressure would the cylinders have to hold? I wouldn't think it

would be a lot but I don't really know. That would dictate the wall thickness

and such. I read they need to be at least 60cc.

Any info appreciated. I'd like to know a bit more about it and try to

get it right the first time. Thanks

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I have a pair of FCR Subtanks I'll sell fittings and everything. PM me if your interested.....

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Been reading some threads on TT about some who have fabricated their

own subtanks. I have a couple general questions about how they work.

1) They talk about using a flow control valve coming out of the fork.

It's supposed to be somewhat limiting on the out flow and zero limiting the

flow back in. How much limiting on the out flow? 30%? 50%?

They said some valves are adjustable. Fixed or adjustable I'd need to

know approx.what the flow needs to be, then I'll have some research/

shopping to do @ Grainger, McMaster Carr or somewhere similar.

2) How much pressure would the cylinders have to hold? I wouldn't think it

would be a lot but I don't really know. That would dictate the wall thickness

and such. I read they need to be at least 60cc.

Any info appreciated. I'd like to know a bit more about it and try to

get it right the first time. Thanks

I just went through the process your doing now, and I now have all my parts to build it, Im just waiting on a tap.

If you are willing to drill and tap the bleed screw hole, there are a lot of easy ways to build them.

I would highly recommend you use a flow control valve, that way you can fine tune the sub tanks performance. Depending on who you ask, most people do not recommend a flow control with a check valve, but rather a bidrectional one, that regulates in both directions. I did not go that route yet, but after testing I may go that way.

Enzo regulates in both directions on theirs.

As to 60cc's of volume, that seems really high for one sub tank. If your sub tank volume gets too high, i read something about getting poor performance due to improper pressure difference between the forks and the tanks. I think you should keep the sub tank volume under the air volume present in your fork.

I am currently using 30cc's per tank, so 60cc total, although I have a second set that are 45cc's.

I found my fittings from legris, they have the best selection and product I have seen from my searches, and as such I was able to not tap the bleeder hole.

If your worried about air flow, it will not be the bleeder hole as your problem, but internally in the fork. I don't know about showa, but the current kyb forks are not going to benefit without some enlarging of the internal holes, and it becomes obvious when you see those holes, they are extremely small for the amount of air movement necessary.

pm me with any more questions, i can send some pictures of what I used, and where I got it.

also, I will be testing it soon, so if you wait a little bit to build yours, I can give out what volumes I went with, settings, and oil height adjustments.

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I have a pair of FCR Subtanks I'll sell fittings and everything. PM me if your interested.....

MXR, Appreciate the offer, sounds like a good deal but this'll be for the learning experience as much as getting the tanks.

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I just went through the process your doing now, and I now have all my parts to build it, Im just waiting on a tap.

If you are willing to drill and tap the bleed screw hole, there are a lot of easy ways to build them.

I would highly recommend you use a flow control valve, that way you can fine tune the sub tanks performance. Depending on who you ask, most people do not recommend a flow control with a check valve, but rather a bidrectional one, that regulates in both directions. I did not go that route yet, but after testing I may go that way.

Enzo regulates in both directions on theirs.

As to 60cc's of volume, that seems really high for one sub tank. If your sub tank volume gets too high, i read something about getting poor performance due to improper pressure difference between the forks and the tanks. I think you should keep the sub tank volume under the air volume present in your fork.

I am currently using 30cc's per tank, so 60cc total, although I have a second set that are 45cc's.

I found my fittings from legris, they have the best selection and product I have seen from my searches, and as such I was able to not tap the bleeder hole.

If your worried about air flow, it will not be the bleeder hole as your problem, but internally in the fork. I don't know about showa, but the current kyb forks are not going to benefit without some enlarging of the internal holes, and it becomes obvious when you see those holes, they are extremely small for the amount of air movement necessary.

pm me with any more questions, i can send some pictures of what I used, and where I got it.

also, I will be testing it soon, so if you wait a little bit to build yours, I can give out what volumes I went with, settings, and oil height adjustments.

Thanks aggiemoto for all the info. I will definitely keep these things in mind

as I sort through all this. I also found alot of info on another forum on building

them including some hardware part numbers. I have WP forks. (That might tell

you what forum I was on.) I suppose at some point I'll just jump in and start

and see what happens, but I will get back w/ ya first to see how it all went.

Good luck with it. Appreciate Ya!

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