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04-up (06) RM 250 Fork Oil

By hefe055,
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hefe055

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Hey I need some advice on the amount of fork oil to run on the Showa's on my RM 250.....I have an 06 that's been sprung for my weight perfectly. Im 6'3 195lbs with .46's intermediate speed. For some reason Ive NEVER liked these forks and cant seem to tune the harshness out in the midstroke....my Honda showa's were decent but wow these forks are downright scary at speed. Currently im at 335 - 340cc's and wanted to know if anyone recommends going less on the oil. Stock is 350cc's and no matter what I do slam or case anything they wont bottom I still have 2" of travel left 100% of my riding. They also feel as if they never compress coming into a corner and a lot of times off jumps the front end kicks up. Its near impossible to ride at full speed because they try to rip the bars out of my arms, like I said the springs are fine and even at like -15 out they still act the same.

 

I know the fork oil height is the culprit.....just wanted to know what people, even suspension tuners may recommend running?

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hefe055

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Yea I was thinking it should be WAY lower....just didn't have a baseline of how far lower to go. I rode the exact same bike with suspension revalved and set up for a 160lb rider of the same speed and was blown away at how good the bike felt once the forks behaved the way they are supposed to even though it was incredibly soft. I figured I could get close with springs and oil until I can get them revalved but holy hell those forks are scary as they are currently.

 

Im going out to the garage right now to drop 20cc's out and see how she feels tomorrow ....provided these santa ana's die down

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hefe055

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How did the forks feel with less oil?

What level and oil weight u at now as I've bin experimenting on my spare forks and have found lovely spring weight but not bottoming out.

Cheers

 

I havent had a chance to try them yet, last weekend the winds were still pretty bad but I plan to ride it this weekend for sure. I am currently at 315 or 320 cc's and I know that may be a little low or it could be dead on but im sure it will bottom out so ill have to be razor sharp on bigger jumps. Before I was running 335-340 and it was BUTALLY HARSH no matter what I hit or shorted it would still have 2+" of travel left and had the bottoming resistance of a works fork haha....I am not as critical about the shock although I check my sag regularly but I HAVE TO have good forks because I ride a little mor over the front end which is where I get my feedback on the bike and how it is working. If my forks suck i cannot ride the bike to my potential as of now they are/were scary

 

With that being said, I drained 20cc's out AND regreased all my linkage in an hour and a half! I did do the "Garage bounce test" and they felt pretty amazing im eager to get to the track and see what a difference it made. I anticipate ill have to add 5-10cc's at most but the front end feels as if it will dive in a corner now ....... anyone else have any input?

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Hydrodydrododecahedron

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Yep I ride realy over the front of the bike also, after riding with these new fork springs I've got in I've found that my hands are blistered and my travel decreased but the bike feels so much better on jumps and berms.

I want to work with the new heavy springs so will lower my fork oil quantity and start from there. I believe this to be the key as softer springs are to soft.

As I said in my other post I Spose I could put one soft spring and one hard spring in forks if I can't make it work with levels of oil.

Cheers

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hefe055

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I am 6'3 195lbs and can run midpack intermediate when my bike is dialed. Currently have .46's being as tall as I am its near impossible for me to not be over the front end. On jumps 50% of the time was an unpredictable reaction either butter smooth or a violent kick up. It felt as if the front end would reach a certain point in the travel and say "thats is not moving any further" so it would force the bike to kick up. 

 

I know there is sheer brilliance in this bike once i get the forks dialed....i have ridden one and it was AMAZING

 

Also going with a 6oz FWW its the lightest one made and i LOVE the explosive power but if you have a heavy throttle hand the bike revs out way too fast for me and upshifting to 4th is not an option on most socal tracks unless they are big and long if i grabbed 4th on a normal track its like reloading a cannon and on short runs that would be dangerous id be over jumping things by a mile.

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Hydrodydrododecahedron

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Yeah I changed the gearing on mine to try tame the suspension movement at rear and front I'm running 14 front sprocket and 50 rear. The tracks I Ride are mainly 4 th sometimes 5 th gear, hitting jumps is quite a fast affair so it gives me the shits when the forks don't use all their travel leading up to a big jump and the bars are almost being ripped out my hands. Blisters and bruised shoulder muscles.

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hefe055

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Going riding moto tomorrow ill report back on the results.......have extra fork oil to add and fine tune them. Anyone know an acceptable range of comp and rebound settings to work wit? I mean for example no more or leess than 8-12 on comp and 8-12 on rebound. I want to test clicker ranges and if they don't work I can add oil in 5cc increments then repeat until I get it right.

 

Im 100% certain the forks can be made dam good without a revalve if I can hone in on the correct oil level, those TC Showa's were great on my Honda's and I was able to get them working

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hefe055

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Yeah I changed the gearing on mine to try tame the suspension movement at rear and front I'm running 14 front sprocket and 50 rear. The tracks I Ride are mainly 4 th sometimes 5 th gear, hitting jumps is quite a fast affair so it gives me the shits when the forks don't use all their travel leading up to a big jump and the bars are almost being ripped out my hands. Blisters and bruised shoulder muscles.

 

Ok so I finally rode today annnnnnnnnnnd HOLY BEAUTIFUL FORKS!!!!  That 20cc's which now puts me at 315cc's was a miracle!! I felt like I was riding a completely different albeit a MUCH  better bike. I have NEVER had the performance this bike gave me today EVER. I shorted and slammed everything I could, just to see where the limit was and it was like a bed of pillows that never gave me the harsh slam of bottoming out easily and blowing through the travel like dropping that much oil in the forks normally would cause, the chassis was balanced and I finally felt the true RM folklore I mean this bike is amazing once setup and I feel it doesn't need a revalve anymore it cut the sharpest most accurate line +.

 

The oil did the trick, this bike tracked straight and stayed glued to the glued to the ground, my front end dove into corners and held its line as if it were on rails. I am literally speechless at how good this bike became, now I know I may seem a little excited but the change was astounding and was everything I had hoped for. I am blown away at how Impressive this bike is now.....I didn't even take time to fine tune it as I couldn't get off the bike at all.....it was so good and such a relief to ride fast that I kept riding and riding as much as I could fit in. I still feel there is room for improvement beyond what I felt today but it was so dam impressive as is, that I just wanted to enjoy the ride for the day it didn't kick up on jumps and absorbed everything I could throw at it and it jumped flawlessly 100% of the time I actually felt like myself again i.e. scrubbing jumps and pushing my speed faster and faster to where I used to be I am looking forward to riding more, wish I could take a sick day tomorrow because I finally got the bike where I wanted it  and FINALLY am comfortable enough to push it ............long story short the RM manual must have a typo because at 315cc's it is incredible which is confusing as to why Suzuki would suggest it to be 350cc's, I promise if you do this and start with the clickers at 10c and 10r as a baseline you can go from there and +/- fork oil as you see fit, I still think I can drop to 310cc's but also am confident I can tune it out with clicker adjustments because the bottoming resistance the forks retained is SUPERB!

 

I am now convinced that 90% of all riders can get their suspension of most modern bikes (thinking modern is anything 93 & up) these days to within 99% as good as a revalve without having to pay through the nose by simply getting the correct springs and researching via TT or even goggle to read what oil height most are running and/or learning how oil height affects the forks and applying it to your bikes suspension could alleviate almost every problem riders complain about. As you can probably read through my enthusiasm in this post I am proud & was able to learn these basic items I can try and avoid paying for a revalve which would've been unnecessary now that I have it dialed (yes it IS that good) ....which opens up my budget for a porting job, thinking Eric Gorr anybody else have suggestions? Also I am getting an oversized front disc kit, and a 6oz FWW and currently I have a FMF fatty/outdoor power core length silencer, it was not very impressive for this bike. Id like to get a PC or Bill's setup but Ill live with what I have although IF I can get the port/fww/oversized disc I am convinced that and this will go down as the BEST bike ill ever ride and I plan to keep it forever and just add to my collection that sadly I had to sell off but Im making a comeback on my collection...

 

Next:

Another 04-up RM250 or a 99-up YZ250 (If I find the YZ absurdly cheap)...this would be my hills freeride bike so I can keep this 06 dialed to the track

05-up YZ or RM125 adding Eric Gorr's 144 stage 3 ported kit for kicks

1991 - up CR500 for the desert and random rides....I dislike 450 thumpers so I need something that can cruise the desert with the 450's but keep my 2 stroke man card here haha although I will probably end up getting a 450 if I find a smoking deal on it but it is the last on my list and it would get ridden maybe 4 times a year.....I love 500 2 strokes and can easily ride one anywhere a 450 outdoes a 250 2 stroke like the dunes and ling desert.

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Grand Master

GHILL28

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Just to verify, your forks are the ones with the long sleeve with the PVC cone piece at the end as an upper spring seat right?  I know the RM forks changed a few times through the 2000's.

 

I have an '05 and I noticed a little bit of funny stuff going on in the midstroke.  Still have to tweak other things like the rear sag and stuff too, so I didn't pay too much attention to it.

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  • 2 months later...
Grand Master

GHILL28

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I'm 6', and 185# before gear with an '05 RM250.  Wear a camelback with some tools and a 3.4g tank, so I'm running 0.47kg springs from an '08 RMZ450, and 315cc of oil.  The progression and bottoming felt REALLY good on these.  Very good balance of springrate and oil height in the forks.

 

About the only things I'd need out of a revalve on these are a little bit less sting on rocks and super high frequency hardpack braking bumps, and a little more initial resistance to dive in sand, so they're real close and just some minor tweaks needed.

 

The rear shock with the rebound separator nut doesn't really need much.  Maybe just a slight reduction of HSC for some rocky stuff?  The RSV makes the shock work awesome.  The adjusters actually do what they're supposed to without the extra bigass hole in the main pressure chamber on compression.

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GHILL28

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Yup.  Midstoke was pretty harsh with 350cc and wouldn't get anywhere near full travel.  315cc I come close to bottoming basically jumping into whoop sections on fast offroad stuff but maybe 1-1.5" shy, which is right where I want it.

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Grand Master

GHILL28

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I never did get my 06 dialed.  My last test I dropped down to 340cc and noticed an improvement, but I didn't know you guys were going so low!

 

Anyway, now I have transmission problems again...I kind of hate this bike...

 

Got a complete 2005 motor if you want to get something fresh in there.  Probably 40 hours on it max.  New piston and Rekluse EXP with 1 ride on them.

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  • 1 year later...

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