springs upgrade?
  • indianFighter
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    by indianFighter » Wed May 29, 2013 4:14 am

    I asked about damper oil because the service manual has listings of fluid capacity for the forks; in the tubes it says 408 cm2 but below that it says fork damper 187 cm2.

    So do I need to fill the fork damper too with oil even if I'm not opening it up to service?

    I got the compression/rebound standard specs from the service manual too. I'll run it standard and then adjust from there. Not to sound like a noob but when the mnaul says 12 clicks out from fully in means from fully soft right? Means turn it in counter clockwise to go fully soft then turn it clockwise 12 clicks.

    In the tyres I'll run 14/14 psi front/rear to start off with, should be fine as a start point for hard park dirt right?
  • indianFighter
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    by indianFighter » Wed May 29, 2013 5:56 am

    Ok some confusion; the 2008 owner's manual and the service manual for 2008 state the fork oil capacity for stiffer .48 kg springs is cm2 402 standard, 410 max and 314 min. For other years it is vastly different.I'm putting in .52 kg springs so 375 cm2 will be ok? Or should I go for the RT recommended 350?

    What changed in the 2008 forks form the earlier ones and 2009 that warranted such a huge change in fork oil volume?
  • der_berger
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    by der_berger » Wed May 29, 2013 7:59 am

    i know on the 08 they changed the frame geometry and the fork rake to allow for better steering, so i think that is why there is a jump in the fork oil level between the models.

    since you are going to have the forks apart already id change the oil in the dampener even if your not planning on servicing them
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    JimDirt
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    by JimDirt » Wed May 29, 2013 11:18 am

    indianFighter wrote:I asked about damper oil because the service manual has listings of fluid capacity for the forks; in the tubes it says 408 cm2 but below that it says fork damper 187 cm2.

    So do I need to fill the fork damper too with oil even if I'm not opening it up to service?

    I got the compression/rebound standard specs from the service manual too. I'll run it standard and then adjust from there. Not to sound like a noob but when the mnaul says 12 clicks out from fully in means from fully soft right? Means turn it in counter clockwise to go fully soft then turn it clockwise 12 clicks.

    In the tyres I'll run 14/14 psi front/rear to start off with, should be fine as a start point for hard park dirt right?


    Its a good idea since you dont know how long its been since last change , BUT you can get away with just the outer oil since it will be dirtier than the inner chamber , again as i stated IF the damper rod extends fully it should be ok to leave it for another time , but its really not that hard to do

    As far as clickers go , its all the way clockwise (stiffer) then out X turns

    Out/fully soft/counter clockwise
    In/fully hard/clockwise (settings based off fully IN then OUT to setting number)

    Tires should be fine , again , experiment , different brand and/or compound tires work differently under the same pressure , so you have to mess around with the pressure to find what works best in each situation , but generally you want a stiffer (less sidewall flexing or rolling , not necessarily a harder compound tire) tire for hard pack
    Last edited by JimDirt on Wed May 29, 2013 11:36 am, edited 1 time in total.
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    JimDirt
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    by JimDirt » Wed May 29, 2013 11:29 am

    indianFighter wrote:Ok some confusion; the 2008 owner's manual and the service manual for 2008 state the fork oil capacity for stiffer .48 kg springs is cm2 402 standard, 410 max and 314 min. For other years it is vastly different.I'm putting in .52 kg springs so 375 cm2 will be ok? Or should I go for the RT recommended 350?

    What changed in the 2008 forks form the earlier ones and 2009 that warranted such a huge change in fork oil volume?


    Again , (though i re-valved mine) I am running 365cc with 0.52 springs (for Off-Road) , but i have 0.49 in my R and am still running 365cc , its a happy medium between the minimum and stiffer capacities , and you can always add oil IF you bottom out more than 1 or 2 times on the entire track

    Its ok to bottom 1 time on the largest jump , but not all the time , again , using a Zip-Tie you can judge your suspension travel , try riding the track everywhere but the jumps , and see where the Zip-Tie is , this will give you a good overall visual of how far your suspension is moving (riding your normal speeds/aggressiveness) , then note how far it drops when riding the track including all the jumps (at your normal riding speeds/aggressiveness) , if it is constantly riding lower on the fork , then add 5cc of oil in each leg and try again , do this till you get about 2" from completely bottoming on the largest jump , and you should be where you need to be

    What changed was the valving and i believe the thickness of the fork tubes themselves ,(less/more flex) which designates the basic stiffness of suspension
  • indianFighter
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    by indianFighter » Fri May 31, 2013 3:02 am

    Alrighty thanks guys. One last question, what rider sag do you aim for for mx?
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    JimDirt
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    by JimDirt » Fri May 31, 2013 10:34 am

    Sag is kind of a preference thing , recommended is 100mm , but i find 102-105 works better for my R (but its a 02 so the frame geometry is different than later years), but i also run my fork tubes 6mm up in the clamps , if you have plenty of steering or too much (if the bike knifes in corners) you can either lower the tubes in the clamps , or add sag , either will give the same basic affect
    Last edited by JimDirt on Fri May 31, 2013 2:39 pm, edited 1 time in total.
  • indianFighter
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    by indianFighter » Fri May 31, 2013 12:04 pm

    Yes especially in tight corners it feels like I have too much sag. I'll start with 100 and experiment from there. I love this bike
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    JimDirt
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    by JimDirt » Fri May 31, 2013 12:17 pm

    So it pushes in corners ??
  • indianFighter
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    by indianFighter » Fri May 31, 2013 12:19 pm

    In tight corners it feels like it's going to cave in. Oversteer kind of feeling.
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    JimDirt
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    by JimDirt » Fri May 31, 2013 2:33 pm

    OK then you need MORE sag not less , more sag will lower the rear and take away steering , less sag will raise the rear and quicken the steering , you can LOWER the forks in the clamps (do not go any farther than FLUSH with the cap and the top of the fork tube) , if you are already there , then adjust with your rear sag , you can go to 110 without issues , but i think going to 103-105 should solve your knifing issue

    You can also install taller bars OR put risers on , this will put your weight farther back on the bike and will help with knifing , i ride way over the front (i can read my number plate while riding) so i put 30mm risers on with RC bend Fatbars , and it feels more comfortable , i have about 20mm of rise on my X , with 10mm risers and Pro Taper Pastrana FMX bars , i am only 5'10" , but prefer the taller setup , it completely changes the ergonomics of the bike , makes it feel longer and not so cramped in the cockpit and seems to turn more fluid and controlled with my weight farther back
  • indianFighter
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    by indianFighter » Sat Jun 01, 2013 11:08 am

    All done guys; changed over everything. I didn't use the lock rings in the rebuild kit, the stock ones looked better. And one set of bushings which go at the top of the damper had play so I reused the old bushings as they looked and fit fine.

    350ml oil felt a bit less so I filled it to 400. The race sag was 100 by default so didn't need to adjust. I set the compression and rebound in the front to as it was before. The rear I hadn't touched while changing springs.

    Sitting on the bike it feels feels a lot better and stiffer, not overly bouncy. Going to test it at the track tomorrow and also in the novice race after that tomorrow. Will report back. Thanks for all your help guys.

    Jim I've got the stock renthal bars, even I felt I would feel better if they were slightly higher. I'm 6', how many inch risers do you recommend with the stock bar? Or should I change the bar too? I'll check out the knifing issue tomorrow as well. Problem is my tyres are shot too, so can't really blame suspension here.
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    JimDirt
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    by JimDirt » Sat Jun 01, 2013 10:34 pm

    Sorry been busy all day

    The stock bars are lower than the RC Bend Fatbars that i have on mine , i would go 10-20mm higher than stock (i believe they come in 10mm,19mm,30mm,), you can do it with a riser or with a taller bar but its pretty hard to find a tall 7/8" bar , if you switch to 1 1/8" clamps , I would recommend RC High bend ,

    If you go to 30mm risers (figure the height of your current bars where they sit in the clamp , now take that , and stack 2 more tubes on it right there *7/8 + 7/8 + 7/8* and that would be about where 30mm risers would place the bottom of your bars) you might have to swap out your front brake cable with a 450X one for 30mm risers , like i did , it is 6" longer , otherwise your cable will be going right across the center of the number plate and might rub

    http://www.crfsonly.com/catalog/product ... ts_id/1064

    http://www.crfsonly.com/catalog/product ... ts_id/4614

    Look at this chart and compare the size measurements to your current bars

    http://www.renthal.com/File/apps1.asp?t ... &bikedate=
    2020 CRF450R
    2006 CRF450X
    Image
    Weiser , Idaho
  • indianFighter
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    by indianFighter » Wed Jun 05, 2013 3:49 am

    Thanks Jim. The product in the second link is only for aftermarket bar mounts? The applied racing bar mount may work; it has a 15 mm rise for stock bar. But it's asking triple clamp is rubber or solid. Mine is stock so I'm guessing solid? What's a rubber trimple clamp?
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    JimDirt
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    by JimDirt » Wed Jun 05, 2013 4:17 pm

    Yes the second is for 1 1/8" clamps and bars , my bad

    Your clamps are Rubber Mounted , what it is referring to is where the bar clamps go thru the triple clamp (the single mounting point that goes thru the triple clamp), there are rubber bushing/dampeners/grommets to absorb the vibration while riding , there are 4 rubber bushings , 1 on the top and 1 on the bottom of each mount stud that goes thru the triple clamp

    Part #4

    http://partsfinder.onlinemicrofiche.com ... TOP-BRIDGE
    2020 CRF450R
    2006 CRF450X
    Image
    Weiser , Idaho

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