Front fork damping setup

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cheeko
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Front fork damping setup

Post by cheeko » 19 Mar 2016, 00:39

Hi everyone,
I'm trying to setup and adjust the damping on the front forks off my CRM250 which won't be a big deal ONCE I knew how/where they are currently setup.

Because at the moment one damping adjustment screw seems to be hard up while the other never adjusts to full stop.

Thus I imagine that both forks are NOT setup equally.

My question is what is my starting point for both forks since one can not be measured to the same as the other?

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Re: Front fork damping setup

Post by fallenmikethebike » 19 Mar 2016, 09:14

cheeko wrote:Hi everyone,
I'm trying to setup and adjust the damping on the front forks off my CRM250 which won't be a big deal ONCE I knew how/where they are currently setup.

Because at the moment one damping adjustment screw seems to be hard up while the other never adjusts to full stop.

Thus I imagine that both forks are NOT setup equally.

My question is what is my starting point for both forks since one can not be measured to the same as the other?
The bad news is it sounds like one adjuster has seized, and the other one has been stripped.
The less bad news is for all the difference they make to the soggy suspension you're not missing out on much :roll:
The forks will need some disassembly and major repairs to bring them back to useful operation, or swap out the existing fluid for something a little thicker.
There's shed loads of info on the site about fitting CR125 forks BUT, that also requires lots of work, but does improve the front end considerably.
Mike
VFORCE REEDS-MUGEN HEAD AND BARREL-WHITE POWER-ALL ON MY WISH LIST!!

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cheeko
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Re: Front fork damping setup

Post by cheeko » 12 Apr 2016, 11:27

Hi Mike (and everyone else),
Sorry for the late reply.
After taking the forks apart here is what I have found, and am puzzled as to how to fix it now.

Attached photos 1, 2, 3 correspond to described issues 1, 2, 3 on the schematic (also attached)

1. I noticed that on one cartridge assembly the press fit between the inner and outer is no longer. Problem 1. the amount you see protruding past the back face is the amount of movement.

2. as a result of (or combination of) problem 1, its outer sleeve's press fit on the cartridge assembly is no longer allowing it come away from the cartridge.

3. In turn the sleeve's sliding fit relative to the inner fork tube has become a tighter press fit, thus now leaving it in an inaccessible area at the bottom of the inner fork tube.

Questions:
a) how do you remove the sleeve that's pressed in at the bottom of the inner fork tube?
b) how problems 1, 2 and 3 be fixed as to reuse the existing parts?
c) are there aftermarket valving kits for these CRM250AR SHOWA forks? preferrably fully adjustable kits but any would also do.

Thanks!

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davecee92
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Re: Front fork damping setup

Post by davecee92 » 15 Apr 2016, 20:35

Let me know if you figure out how to fix this as my mk 2 has the exact same problem i think its causing my forks to feel ' sticky '

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Re: Front fork damping setup

Post by gregorious77 » 17 Apr 2016, 20:38

davecee92 wrote:Let me know if you figure out how to fix this as my mk 2 has the exact same problem i think its causing my forks to feel ' sticky '
sticky could be incorrect tightening sequence of the front wheel spindle.

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Re: Front fork damping setup

Post by pudzie83 » 18 Apr 2016, 11:44

As gregorious77 mentioned they're not quite fitted correctly if they're to far in and not straight they will feel odd this will also bugger your fork seals up
VIVA LA CRM!

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davecee92
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Re: Front fork damping setup

Post by davecee92 » 19 Apr 2016, 10:01

I dont think its the front spindle i have redone this a few times i also tried fork pinch bolts etc i have just replaced the seals and bushes i also removed and set both adjusters on the bottom of the forks i think mines is related to the third image (sorry cheeko for hijjacking your post )

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cheeko
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Re: Front fork damping setup

Post by cheeko » 21 Apr 2016, 22:05

No one was responding to my post anyways.

I talked to a suspension pro an he said that problem #1 on my post is actually the opposite to what I thought.
the inner cartridge rod IS supposed to move like this relative to the outside rode. Thereby making the other seized or really really tight, as I still can't get it loose.
However I do not know how to disassemble the cartridge assembly apart to have a look inside and in between the relative rods.

I'm still also left with problems # 2 and 3. The sleeve on the bottom of cartridge assembly is stuck at the bottom of the inner fork tube (label #3). And this I cannot get out

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Re: Front fork damping setup

Post by davecee92 » 22 Apr 2016, 10:49

Not that it helps but i was able to remove the sleeves on mine with a few taps on a wooden bench dont , i also think there was a little clip at the top of the cartridge to dissasemble quite similar to the clips found in pistons. But i never removed it .I could be getting mixed up though. Let me know if you get sorted as mine is the same. Not that its my most major problem right now. Thanks again

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cheeko
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Re: Front fork damping setup

Post by cheeko » 22 Apr 2016, 11:09

I was able to get the tubes separated by removing the seals, washers, wire clip. That was pretty much straight forward.
I was hoping to avoid that but a new seal couldn't hurt.

However the sleeve is still in there. I also tried to tap it out through shocking it but no such luck.

Adding to the problem I noticed that one of the four valve holes on the upper part of the tube is damaged. Raised edge. Must have gotten damaged by hitting against something else through transport or something. But this is a big problem now.

I may just send it off to the suspension pros and see what they can do for me =(

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Re: Front fork damping setup

Post by gregorious77 » 27 Apr 2016, 21:48

CR fork upgrade time!!

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davecee92
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Re: Front fork damping setup

Post by davecee92 » 28 Apr 2016, 09:38

Does the cr fork fit the crm wheels , spindle + calliper ? Ive just had wheels built that were quite expensive and would like to keep them lol

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Re: Front fork damping setup

Post by gregorious77 » 29 Apr 2016, 20:51

check the faq. depends on year I think

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Re: Front fork damping setup

Post by knackeredMk1 » 29 Apr 2016, 22:04



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