Bladder fork design

[russ17]

from what I read the blader fork has 2- volume displacers 1- being the cartridge rod. On a the non bladder forks this displacement of oil (by the cartridge rod ) goes through the base valve. But on the bladder forks it is absorbed by the bladder chamber. 2nd volume displacer is the inner tube charge entering the outer tube. Question 1-is the volume of the oil of the inner tube entering the outer being displaced passing through the base valve or is it still by the cartridge rod. 2 -how or does this change the thought on mid valve floats on this type of design. trying to better understand what is actually going on here.

 

[russ17]

My Questioning is based on what I read from the article which had me alittle confused. But after tearing the forks apart I believe it answered my question.

 

[marcusgunby]

all i can say take out the lot and chuck the bladder and RB as far as you can-braking bumps seem to be absorbed better without the baldder system.

 

[Jeff Howe]

LOL.. I agree. And so did Kawi and Suzi for 03...finally.

 

[russ17]

Bladders in the can! thanks

 

[bscottr]

Originally posted by marcusgunby
chuck the bladder and RB as far as you can

Marcus,
I've got the bladder part, but what's RB?

Thanks,
Scott

 

[Jeff Howe]

Restrictive Barrier, it's the washer/plate that sits on top of the cartridge head, spring sits on top of it.

 

[bscottr]

Shocknut,
Thanks.....add another acronym to my list. ;) If this improves braking bump action, it should do the same for roots, etc. no?

Thanks Again,
Scott

 

[Jeff Howe]

yes

 

[russ17]

Marcus or Shocknut being the bladder system uses the oil lock system ( hydraulic ) for bottoming. By disabling this and not having the elastomer will there be a problem with bottoming

 

[Jeff Howe]

Nope. Set your oil level accordingly and you'll be fine. I took the bumpers out of my YZ forks and converted to oil lock system and love it.

 

[russ17]

Thanks russ

 

[dbrace]

Originally posted by Shocknut
Nope. Set your oil level accordingly and you'll be fine. I took the bumpers out of my YZ forks and converted to oil lock system and love it.

shocknut please explaine how u did this and the benefits. thanks

 

[marcusgunby]

Russ you dont disable the oil lock system with this mod.

 

[bclapham]

are the forks on my 01yz250 bladder or bumper? i assume they are bumpers since i remember marcus showing me the old bladders of the cr and there were nothing like that in my forks. Is it worth taking the bumbers out of my forks? is it an easy job?

thanks

 

[marcusgunby]

Bruce your a bumper:) as to removing them only shocknut can say as i havnt had the pleasure.

 

[Jeff Howe]

There are kits available to do this. You end up with a oil lock bottomout system like Kawi KX's or CR125's. You have to unscrew the top off the cartridge(CV) and then replace with a 2.5" deep cone. Piston is attached to the rod just like on a KX/CR KYB fork. It's actually more involved but thats the basics.

This is one aspect of forks where Jer and I always disagreed, so he's probably gonna punch me again. But I like these things because of the consistency in performance compared to the cv (don't have to worry about leaks), and I like the more progressive bottoming feel. There are different toleranced pistons available and I've tried them but I prefer the ones that come with the kits I use. Really these things can be tuned how you want them if you know what to do with them. I can't imagine my YZ forks without them anymore. For me.. the additional expense and all, it was one of the best mods I've done to my own forks and lots of the customers love them as well.

Another aspect, is anytime you can improve your bottoming control you don't need to worry about so much in terms of valving. I feel this is good. I also think the stock CR and KX setups are a bit loose.

 

[marcusgunby]

Thanks for that info Jeff-i dont think i will be doing a conversion as it does sound involved(anyway the KX has a oil lock as well:).However im not to sure about this CV i have in the 03 KX-i will have to see how reliable and consistant it is.From what i have read its very hard to check the CV or repair-i dont like any system that keeps me out:(.The japs seems intent on peening and all sorts of ideas to stop us taking stuff apart-stupid as we always will.The WP/Ohlins etc seem designed to be serviced and rebuilt.

 

[bclapham]

yep, sounds like my bumpers will stay put. the more i think about it though, theres nothing better than a nice pair of bumpers to look at!

 

[russ17]

Marcus wheres the oil lock built in the new kx's I thought that it was just the CV. man I should of looked a little closer at that one. I didn't bother with any mid changes on the 125. wanted to see the difference so I didn't open that one up( cartridge that is ). But I did on the kx250 I thought it had a bumper .But that was a while ago.

Shocknut I like the thought of bottoming control and not having to worry in terms of valving. but if this oil lock system is speed sensitive could this become a problem with high speed hits with little fork travel. I don't know much about these kits

 

[marcusgunby]

Russ it has a bumper and a small oil lock at the bottom -im not sure how much bottoming resistance it creates but i felt it when bleeding the forks.I could be wrong and maybe it isnt a oil lock but i looked and felt like one.After missing the CV i dont feel i know anything anymore:(

 

BTW went out on my bike last weekend-very muddy again(i can send the vids if you have broadband)the shock felt a tad softer but the forks i cannot comment on-didnt really get  afeel for the performance-needed the other modded fork to compare but his bike was out of action.

 

[marcusgunby]

heres a pic of a new KX and the local mud.

 

[russ17]

Yeah! I know what you mean about the weather I haven't seen the ground here in months but it suppose to get above freezing this week end and where riding. putting the spikes on. haven't been on the bike in awhile and the first gncc is around the corner

 

[bclapham]

Originally posted by russ17
Yeah! I know what you mean about the weather

yep me too, its lovely and sunny here, i am sure the local tracks are busy, i would bet all the pros are out there getting ready for the next SX.......

However, i am stuck in my bloody office 7 days a week, about 16hrs a day right now, teetering on the brink of a nervous breakdown! :silly: good job i get some virtual 2 wheeled therepy on DRN!

Marcus, look at the state of that nice new bike, you should take more care of your toys, next time i see her, i gonna tell your mum to give you a good clip around your lughole! :p

 

[marcusgunby]

Bruce it isnt mine.Mine looks alot older than that:(