:thumb: :worship: Thanks Jeremy. Yes that is alot better. A little harsh for some of the suspension "specialists" out there :eek: , but I guess the truth hurts sometimes. I had just gotten myself confused w/removing the midvalve and the mod that converts it to a check valve. I'm up to speed now. :thumb:
midvalve
- Thread starter Papakeith
- Start date
marcusgunby
LIFETIME SPONSOR
- Jan 9, 2000
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Russ i think i understand better now-he removes the cv but then reinstalls it? lots of work that is.On the 'scary one' i meant its scary what the owner did-the hole isnt clear as he filled it with liquid metal-he wanted me to show people what not to do as its very easy to go too far.
Jer the pistons pics were sent to me by the 'mentor' notice they are gold nowdays-must have been a hard choice to use that material;)
Jer the pistons pics were sent to me by the 'mentor' notice they are gold nowdays-must have been a hard choice to use that material;)
Jeremy Wilkey
Owner, MX-Tech
- Jan 28, 2000
- 1,453
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KTM-LEW..
The truth sometimes hurts us all... I've got lots of skeltons, but I've got a really big thick padilock on that closet.. :yeehaw:
BTW the care package is finally ready.. We / I went ahead and tested it... All I can say is wow! Hold on to your hat.. This is the biggest thing since the fork became cartridge...
Marcus,
Its all smoke and mears (coatings) bro, you'll find no brass in that piston.. ;)
BR,
Jer
Jer, Sounds good. Our weather has been pretty ugly. Only had a couple decent days the last 6 weeks or so. I figured you would let me know what or when.
Oh, I took a class on the phone, :o so call if you want. :)
I think Marcus was hoping "thars GOLD in them forks". :laugh:
Hmmm....hope my valves and valve springs will last thru some testing.... :flame:
Oh, I took a class on the phone, :o so call if you want. :)
I think Marcus was hoping "thars GOLD in them forks". :laugh:
Hmmm....hope my valves and valve springs will last thru some testing.... :flame:
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marcusgunby
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- Jan 9, 2000
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Well my forks got me today-filed off the peens on the rebound nut-tried to remove the nut-worked it forwards and back a few times-filed the threads again, and it still pickup up the threads and damadged them-i hate this rebound tap.Ended up using a M5 die to get some decent new threads.Hope it holds:(
Marcus, I can tell that is going to happen to lots of people on 03 KX. RT better make some of those rebound stems and get them in stock. If you can get a tight nut on it you'll be fine though as the force is not placed on the nut at all when topping out...like it can be on a shock. Doesn't take a lot to hold that rebound assembly together really so don't worry about it too much.
marcusgunby
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- Jan 9, 2000
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Thanks Jeff-im a bit happier now:)ahh yes i can picture it in my head- its the tap itself that holds the fork together when topped out.I think the nut will hold on to hold the rebound stack in place.Im fairly sure Kwak doesnt sell this part on its own.I still dont understand why its so puny.Is there a better method to remove the peens-i was thinking of trying to punch them inwards???
bclapham
LIFETIME SPONSOR
- Nov 5, 2001
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so the nut we are talking about is the one that holds the piston assembly onto the stacks, correct? On the YZ KYB forks this nut is a M8 thread and the rebound stack uses 8mm shims and the compression stack uses 11mm shims around the collar. So i am assuming from this that the RM and KX KYB fork has a smaller nut on the end and as mentioned earlier, these forks use 6mm rebound shims and 8mm compression shims.
so my question is:
what is the difference on damping/flow of a shim stack that uses a smaller hole? (even if the outer diameters are the same for each stack)
or can we not answer this question since because the rod diameter is thinner, then the 2 forks are probably using slightly different pistons?
do the KX forks have the same "top out" spring behind the midvalve?
so my question is:
what is the difference on damping/flow of a shim stack that uses a smaller hole? (even if the outer diameters are the same for each stack)
or can we not answer this question since because the rod diameter is thinner, then the 2 forks are probably using slightly different pistons?
do the KX forks have the same "top out" spring behind the midvalve?
marcusgunby
LIFETIME SPONSOR
- Jan 9, 2000
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All questions right in the 1st paragraph-however i dont know about the new RM125 as it has showas-the RM 250 uses KYBs.
Good question on the damping produced by 2 shims with the same o/d but different i/d.I await the answer from our gurus.
The KX fork does have the top out spring.
Good question on the damping produced by 2 shims with the same o/d but different i/d.I await the answer from our gurus.
The KX fork does have the top out spring.
Marcus, I saw your picture showing what not to do when drilling out the peens. Can you explain it a bit more. I'm totally new to this and think I may have done the wrong thing. To drill the peens out I used a small drill bit and drilled until I could see the outter tube inside edge against the part that unscrews from the outter tube. Anyway, how much heat do I need to apply. The oil is smoking and I am worried to apply too much heat for too long.. HELP and THANKS
marcusgunby
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- Jan 9, 2000
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On my KX kybs i had to get the oil smoking to break the threadlock, however a good whack with a hammer on the part thats peened helps break the threadlock.Not sure i understand your decription of the drilling of the peens-it doesnt sound like you have gone too far-you can get away without drilling the peens but its risky.
Thanks, I posted in two threads because the midvalve thread is so many pages...anyhow...I ended up ok, didn't drill too far. I was able to set my lift at just under .5mm and I removed one of the three 27mm shims to lighten up the mid-valve dampening some. I've also lightened up the BV stack some by removing the shims that Yama doubled up on this year (03 250f) compared to the 01/02's. 5wt oil. Sitting on the bike they don't feel as soft as before, possibily because of the decrease in lift. If the bike stays up in the travel but soaks up everything I will be a happy rider.
marcusgunby
LIFETIME SPONSOR
- Jan 9, 2000
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I think it will stay up in the travel, you will need to go alot softer on the base valve-more than you can imagine.
marcusgunby said:
Marcus...You can use a fine grit grind stone and grind just enough below the nut to get the top threads. I like to then chamfer the edge lightly then wire wheel it. Makes a nice clean looking job. Wrap the piston ring with electrical tape first.
doc
Jeremy said:
Hey, dude, you holdin' out on us? I need some of that "WOW!" in my forks.
I gotta say, this is the most helpful thread I have read on this subject. Thanks guys!
Also, most of the street forks I have looked into only use a check-plate instead of a shimstack for the midvalve. Are you saying it would be highly beneficial to add a shimstack in place of the checkvalve (compression side of rebound piston)? And when you are tuning the shimstacks, where is it best to start? Adjust the overall HSC damping coeffecient first and go down from there?
For reference, I am dealing with several different forks. They all have 20mm cartridges with the basic 2-valve setup.
Hey, dude, you holdin' out on us? I need some of that "WOW!" in my forks.
I gotta say, this is the most helpful thread I have read on this subject. Thanks guys!
Also, most of the street forks I have looked into only use a check-plate instead of a shimstack for the midvalve. Are you saying it would be highly beneficial to add a shimstack in place of the checkvalve (compression side of rebound piston)? And when you are tuning the shimstacks, where is it best to start? Adjust the overall HSC damping coeffecient first and go down from there?
For reference, I am dealing with several different forks. They all have 20mm cartridges with the basic 2-valve setup.