Jump to content

2014 CRF 450 - Suspesnion super harsh in chop

By bearpah,
in Motorcycle Suspension

 Share

Recommended Posts

Apprentice

bearpah

Posted
Posted

Well I just picked up a 2014 CRF 450. I have always ran conventional springs and now with the new PSF, I know slim to none about. I weigh 225 and the bike is set up for someone who is 170-200 lbs. Now I set the front PSI to 35 lbs. and adjusted the clickers out 13 to standard spec. I went out and did two motos with it set like that and I thought that my hands and arms were going to fall off. The big jumps is fine and works great, the small chop is the killer. The suspension doesn't seem like it wants to absorb anything. So after moto 2, I dropped  the PSI in the forks down to 30, the minimum actually less than minimum by one pound. I went out and did  moto 3 and it was better but not anything to write home about. I also still left the compression set and the standard setting of 13 clicks out.  The other thing that I noticed after I did moto 3 is that i still have not used the entire stroke of the suspension. I have about 2" left to the bottom of the fork leg.

 

So my question is due to the fact that I am a heavier rider than recommended for the factory suspension. How can I adjust the suspension in order to get it more plush and not so harsh in the chop. Or do I just have to send it out and have the suspension revalved and new rear spring put in. I forget to mention I set he sag and the rear felt totally fine. So if someone could give me some pointers on what direction to go with this super stiff front super, I would greatly appreciate it. Thanks for your guy's time.

Link to comment
Share on other sites
  • Replies 56
  • Created
  • Last Reply

Top Posters In This Topic

  • 7

  • 8

  • 8

  • 11

Popular Days

Top Posters In This Topic

Popular Days

Popular Posts

harrperf
harrperf

What I would describe as cavitation would not be the same issue you are describing.   Large influx of air in the oil is NOT a result of cavitation via these pressure differentials.  IE - where did

harrperf
harrperf

At your weight I'd be adding LOTS of midvalve into the bike. If you really focus on the forks - I think you will find the first 6 inches for you are blowing through. Get either an oring or a tierap

racerfmx450
racerfmx450

You are right!, The Major Problem it's the seal so the foamy oil comes into the Cardtridge. but on this Fork we have more issues since the Pressure is the same inner and Outher Cartridge!!   a

Veteran

GDI70

Posted
Posted

You need to run a higher Psi for your weight, but forks may get pretty stiff with stock oil height. Try lowering oil to 215cc, and run psi at 40. This will hold bike up a bit more for you and if you need to, you can add more oil in 5cc increments. You can fine tune psi from there as well. Just a basic adjustment, hopefully it helps a bit. You should be within 39-40 psi valving changes after air/oil doesn't get you where you need to be

  • Like 1
Link to comment
Share on other sites
Mentor

wblake

Posted
Posted

You need to run a higher Psi for your weight, but forks may get pretty stiff with stock oil height. Try lowering oil to 215cc, and run psi at 40. This will hold bike up a bit more for you and if you need to, you can add more oil in 5cc increments. You can fine tune psi from there as well. Just a basic adjustment, hopefully it helps a bit. You should be within 39-40 psi valving changes after air/oil doesn't get you where you need to be

Marc are you saying it wont get better with a revalve?

Link to comment
Share on other sites
Veteran

GDI70

Posted
Posted

no it will get better, but just for simplicity, oil and air will help the cause.

 

i've got a larger rider who is on the same machine. the sponsored kid is hurt, so we need to adjust for the riders' size.

 

i've done several kawis, but only a couple of hondas. most of the riders are very light compared to a 225-240lb. rider.

Link to comment
Share on other sites
Apprentice

bearpah

Posted
  • Author
Posted

I like what I have heard so far. Do to being an air fork now, and if I send it out to Precision Concepts, what exactly are they going to do in order to make the ride more forgiving or plush? I should say, what am I paying for if I can adjust the spring rate myself?

Link to comment
Share on other sites
Mentor

wblake

Posted
Posted

Not sure if it's relevent, but for the 2013 MXA recommends 11c (out) and 10r (out).

clickers are pretty personal to your size, ability, and terrain!

its another few variables to play with...

Start with the adjustments on air and oil. Then run clickers 12c 14r test, and adjust as need be.

i would expect a suggestion of less rebound due to the higher pressure to tell you the truth....but am no expert!"....whats the thought, or is it something you found it works!

Link to comment
Share on other sites
Veteran

GDI70

Posted
Posted (edited)

Just a starting point. He mentioned precision concepts so, it may be an off road application as well. I've always preferred to start mid-clicker to slightly past and work back. Especially if off road is the application. But even in Mx, 12-14 reb can work well.

Depending on track conditions during the Mx a test sessions, they may have found that setting to work well where they happened to be.

Edited by GDI70
  • Like 1
Link to comment
Share on other sites
Apprentice

bearpah

Posted
  • Author
Posted

Ok, I am no suspension guy by no means. But is is fairly easy to adjust your oil level.  What does this entail? I have no fork wrenchs or anything like that?  Let me know, cause I am totally down for trying an figuring out this harsh ride.  I haven't looked in my owner's manual today cause I am still at work,  but does anyone know how much oil the forks come with stock ?


Ok, I am no suspension guy by no means. But is is fairly easy to adjust your oil level.  What does this entail? I have no fork wrenchs or anything like that?  Let me know, cause I am totally down for trying an figuring out this harsh ride.  I haven't looked in my owner's manual today cause I am still at work,  but does anyone know how much oil the forks come with stock ?

Also forgot to ask what this means  "
3,7 to 3,8 Nmm ballancespring" or what does in refer to . Thanks

Link to comment
Share on other sites
Grand Master

harrperf

Posted
Posted (edited)

At your weight I'd be adding LOTS of midvalve into the bike.

If you really focus on the forks - I think you will find the first 6 inches for you are blowing through.

Get either an oring or a tierap installed, in a perfectly flat feild or parking lot - go like third gear then hit the brakes as if you were coming into a turn (stand up etc...) Look at the strap - You will be very surprised at how muhc travel you are using with NO bumps in the equation!

Edited by harrperf
  • Like 2
Link to comment
Share on other sites
Grand Master

harrperf

Posted
Posted

The 14 have a new style mid Piston!

It' just a larger version of the 12 piston .

( 3 port)

The 12 Piston does not fit!!!!

"12 28mm

"14 32mm

Yes, you need a different valving also but at first i would set the spring correctly.

 

You are totally correct!  I just had one apart yesterday and sure enough it's a one piece three port design.

 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

ThumperTalk

Register a new account Sign In Now
 Share
Go to topic listing
×
×
  • Create New...
Terms of Use
Copyright
Privacy Policy