Full Showa USD fork/RM125 shock conversion

Questions and comments about converting to beefier forks..
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Full Showa USD fork/RM125 shock conversion

Post by SS109 »

I'm so stoked! My KDX will be getting new suspension soon! Just dropped off my '06 KX250f twin chamber Showa forks to my suspension guy. He said he could build me the rear Suzuki Showa shock from his stock of shocks on hand so no Ebay shopping. So, rebuilt, sprung, and revalved for $550-600! Woohoo! :supz:

If any of you guys are looking for a great, honest guy to work on your suspension, at a reasonable cost, Don is your man! He's the same guy that did my white '90 KDX. I highly recommend him! http://zr1suspension.com/

*Edited for clarity!
Last edited by SS109 on 12:09 pm Jun 30 2016, edited 2 times in total.
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Re: Full Showa conversion

Post by Jim B »

Are you trying to make it an off road bike, or keeping it an MX bike? Have you ridden the KXF on the trails? If so, how do you like it? What's the advantage of the Suzuki shock over the Kawasaki shock? Were the '06s still the same bike with different color plastics?
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Full Showa conversion

Post by SS109 »

Sorry, this is a fork and shock swap on to a '98 KDX220.

I have never ridden any year KX250f. However, I do know the '06 KX250f was all new that year with a new aluminum frame (first year for Kawasaki on the 250f), redesigned engine, and all new plastics.
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Full Showa conversion

Post by Jim B »

SS109 wrote:Sorry, this is a fork and shock swap on to a '98 KDX220.

Ah. Keep us posted on how they work on the KDX.
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Re: Full Showa conversion

Post by ecojbr »

You will love how that makes your dx feel
04 kx220 hybrid
03 kx 250
05 kdx 200
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Re: Full Showa conversion

Post by SS109 »

ecojbr wrote:You will love how that makes your dx feel
I'm really hoping it does! After riding bikes with great suspension it was really hard to ride it with the stock stuff. Can't wait to try it out. Sadly, I won't have it done this weekend as my lower triple won't be back from RB until early next week.
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Full Showa conversion

Post by SS109 »

OK, my suspension guy (Don) and I talked a bit about this setup and he wanted to do one thing differently than what others have done on other KDX/Showa swaps. Instead of using the long stock RM clevis at the link he used a much shorter one. I don't know what bike it came on stock but I can find out if you want to do this yourself. He wanted to use it as shortening the shock internally that much takes away a lot of it's stroke and this would allow the use of a stock length spring. The only problem with running the shorter clevis is that it will hit the knuckle (that's what I call it) that the shock bolts to. So, I modified the clevis with a beveled edge on the side where it hits and ground the knuckle just a hair. Now there is about a dollar bill's thickness of gap between the two at full droop. By not shortening the shock internally it made the shock slightly long (by about 5mm) and had to be compressed just a tad to get it mounted. Holding the washers to get the top bolt started while compressing it that small amount was a bit of a pain but, otherwise, was a very straight forward installation. Clearance around the shock looks great so far but I haven't reinstalled the airbox yet. Nearest point is the shock bladder to the frame and it's got about 1/4" clearance at full droop. That should be even better when weight is on it. There is about 3/4" to the pipe so no problems with the FMF pipe.

Final notes. Hopefully I will have my triples back from RB this week and will be able to take her out next weekend. I'll, of course, post up a ride report here. Also, for those thinking about this swap, Don said that the '01 though '06 RM125 is the same physically. Only internal valving and the factory spring weights changed. Ok, some pics!

Here you can see the bevel. It's at about 45 degrees.

Image

Here you can see where I ground on the knuckle just a bit and the shorter modified clevis.

Image

Another view of the knuckle. As you can see, I didn't take much off of it. (bottom edge on the right half)

Image

Installed! The pic is kind of misleading as there is 3/4" clearance between the bladder and the pipe.

Image
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Re: Full Showa conversion

Post by Friedom »

I've got a 90 Suzuki dr350 dirt model shock with adjustable compression and rebound, I wonder if that would be an upgrade to service it and put it on my 92 kdx200.
I've heard nothing but rave reviews about Frank's work. I think I'll give him a call when the time comes.

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Re: Full Showa conversion

Post by SS109 »

Friedom wrote:I've got a 90 Suzuki dr350 dirt model shock with adjustable compression and rebound, I wonder if that would be an upgrade to service it and put it on my 92 kdx200.
I've heard nothing but rave reviews about Frank's work. I think I'll give him a call when the time comes.

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IMO, it wouldn't be an upgrade at all as the stock KDX KYB shock is a decent shock. Going to the RM Showa shock you get (the big deal about the swap) high and low speed compression control and rebound.
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Re: Full Showa conversion

Post by Friedom »

SS109 wrote:
Friedom wrote:I've got a 90 Suzuki dr350 dirt model shock with adjustable compression and rebound, I wonder if that would be an upgrade to service it and put it on my 92 kdx200.
I've heard nothing but rave reviews about Frank's work. I think I'll give him a call when the time comes.

Joy to the world!
IMO, it wouldn't be an upgrade at all as the stock KDX KYB shock is a decent shock. Going to the RM Showa shock you get (the big deal about the swap) high and low speed compression control and rebound.
Thank you for the clarification. Given that either shock will need rebuilt, are they comparable?

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Re: Full Showa conversion

Post by 6 Riders »

Friedom wrote: Thank you for the clarification. Given that either shock will need rebuilt, are they comparable?

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The stock KDX shock is/was considered to be a pretty good shock, even when compared to a KX rear shock.....Sometimes it was considered better than the KX shock. The Showa shock is considered an upgrade because of the "circuits" in it. It is well mannered when riding slow technical trails and when things get fast, it has a "high speed circuit" that kicks in and keeps things smooth. If you are one type of rider or the other, just have the KYB rebuilt and tuned to your specs, if you are like me and ride both track, single track and fast roads in the same day....the Showa is a consideration.
newbbewb wrote:^what he said.
masterblaster wrote:Man 6 riders you rock.
*side note...I'm drunk, so try to read what I'm trying to say, instead of what I actually type
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Re: Full Showa conversion

Post by Friedom »

6 Riders wrote:
Friedom wrote: Thank you for the clarification. Given that either shock will need rebuilt, are they comparable?

Joy to the world!
The stock KDX shock is/was considered to be a pretty good shock, even when compared to a KX rear shock.....Sometimes it was considered better than the KX shock. The Showa shock is considered an upgrade because of the "circuits" in it. It is well mannered when riding slow technical trails and when things get fast, it has a "high speed circuit" that kicks in and keeps things smooth. If you are one type of rider or the other, just have the KYB rebuilt and tuned to your specs, if you are like me and ride both track, single track and fast roads in the same day....the Showa is a consideration.
Interesting. I have another dr350 running the same rear shock, and it definitely seems to sing at higher speeds when we're exploring power line trails. Not always so much at lower speeds though.

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Full Showa conversion

Post by SS109 »

Bike fully assembled and ready to go. No clearances with the air box. Closest it comes is 1/4" right at the top of the spring. After that it gaps out to about an inch. Plan on riding it today and trying to dial it in. I rode up and down the alley behind my house and it already felt better and I haven't touched anything yet, not even sag. Noticed the bike is noticeably taller even though I set the forks 1" up in the clamps. This is going to be interesting!
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Full Showa conversion

Post by SS109 »

Did my shake down ride today. Set the sag at 110mm per my guy's recommendation and went riding. It's like a totally different bike! :supz: This suspension has totally transformed the bike. It is plush in the chop, sticks like glue, doesn't cross rut, and no deflection. He made it do/don't do everything I asked for. I literally did not change one clicker on the forks and on the shock only 1 click up on compression and slowed the rebound 1 click.
Last edited by SS109 on 06:50 pm Dec 20 2015, edited 1 time in total.
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Full Showa conversion

Post by osobad »

Most people know the front forks need to go and need to be upgraded. My personal choice is the 97-99 RM conventional twin chamber. I will find a way to put them on any bike I own. That said while the rear shock is not bad it has its limits at speed the rm rear shock realy helps this bick track at speed. Prob any shock with high and low speed circuits would but the rm showa seems to be the best fit
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Re: Full Showa conversion

Post by Silverfox »

osobad , are you running stock rm 125 forks? I'm in the process of doing the swap now. Have both 96 and 98 Rm 125 forks. The 96's have leaky fork seals and I want to run the 98's anyway but one of them has a few minor knicks on the tube. I may see if I can cannibalize the tube from the 96. Anyways, did you modify the stack? What oil are you running? Springs?
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Full Showa conversion

Post by SS109 »

osobad wrote:That said while the rear shock is not bad it has its limits at speed the rm rear shock realy helps this bick track at speed. Prob any shock with high and low speed circuits would but the rm showa seems to be the best fit
Yup, that shock really settles the rear end down and it tracks straight as an arrow. Put in 34 miles today. I haven't ridden this fast and hard since I had my Gas Gas yet I'm less beat up than any setup I have ever had in the past. I'm loving it! :mrgreen:

Added bonus today, I got to ride with Carlos Servanno! If you know MX from the 70's and 80's you might recognize the name. A true legend born and raised right here in Tucson, AZ!
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Full Showa conversion

Post by osobad »

I have run them stock and they are better than any MX fork without a revalve. I usally have them revalved though. I don't know about the 96 rm forks. I do not believe they are the conventional Twin chamber forks. 97-99 are not upside down but they are twin chamber. I feel like the RM rear shock gives the KDX the stability of a longer wheelbase without losing the tight woods agility it is known for. People don't believe me until they ride it
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Re: Full Showa conversion

Post by Friedom »

osobad wrote:I have run them stock and they are better than any MX fork without a revalve. I usally have them revalved though. I don't know about the 96 rm forks. I do not believe they are the conventional Twin chamber forks. 97-99 are not upside down but they are twin chamber. I feel like the RM rear shock gives the KDX the stability of a longer wheelbase without losing the tight woods agility it is known for. People don't believe me until they ride it
Alright fine I'll start shopping for rm suspension components. Mine needs rebuild, might as well upgrade. Is it a full front end, and how hard?

I.e. what's your final cost for switching over to a RM Showa setup?

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Re: Full Showa conversion

Post by Friedom »

Another note - rmz has different forks, right? There's a set here locally from an 03 for 130$.

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