I realise this video is 6 years old and I'm unlikely to get an answer but it's really helpful. Did you leave the rebound valving stock, how did it cope with the 0.72kg/mm springs? I'm a big lad (255lb) and I've been told I need 0.7 or 0.75kg/mm springs but the stock rebound won't cope? What are your thoughts. Thanks
@MrDuhfactor
Жыл бұрын
We did not change the rebound stack from stock. It is true the rebound may be a little faster than stock, but we did not notice it to be a problem. We ride fast desert, including whoops, jumps, fast chatter, and push really hard on these bikes. We didn't notice a lack of rebound control to be enough of a problem to do anything about. It was so much better for hard agressive riding that stock it wasn't even comparable.
@tattoomiked4612
7 жыл бұрын
Another great video. Easy to see the processes. Easy on the ears also! Thanks
@NeilsIn
7 жыл бұрын
Good ol' johnny cash in the background!
@buaan
7 жыл бұрын
Really interesting MrD, I have never gotten into a shock before so this is a good insight!
@MrDuhfactor
7 жыл бұрын
So much to see !!! LOL
@eveRide
7 жыл бұрын
Always good info... You're the best!
@MrDuhfactor
7 жыл бұрын
Pretty much useless information unless one is a picky buggar who can't can't stop fidgeting.....lol
@emid7976
2 жыл бұрын
Interesting video. Are you using stock oil 5wt or 10-15? Made hyperpro progressive spring update, and they sent 15wt oil, have put all in and now fork is leaking.
@thejohn6614
6 жыл бұрын
I've watched a bunch of your videos and a ton of others. I have two sets of forks for my 02 yz250 both are so stiff. I only get half travel no matter what, and i can jump up and down on the pegs without getting any compression. I've stated messing with the shims after I've done everything else to the forks a dozen times. I don't understand exactly what to do with my shims. I appreciate your videos though. All the info i can get is helpful.
@MrDuhfactor
6 жыл бұрын
john Franklin Did you check to see if you have the proper fork springs for your weight? For what your describing, that would be the place to start....valving doesnt normally cause that....
@thejohn6614
6 жыл бұрын
@@MrDuhfactor yes. It's stock springs. I'm at the top of the weight bracket for these springs. I changed the oil, bushings, and seals. I tried different oil heights and lowered the viscosity to 5 weight instead of 10. I made absolutely sure the forks aren't binding. I've opened them up a bunch of times and inspected everything including the cartridges on the first pair. I found a deal on the second pair. They were full of gunk. I finished rebuilding one today and from testing it by hand it feels about the same. Those forks are off of a 99 and have a different shim stack on the base valve. I didn't open the cartridges and look at the midvalve though. I wanted to see how it would do the way it came.
@thejohn6614
6 жыл бұрын
@@MrDuhfactor everything I've read says that these stock forks suck because of how stiff they are, but they can be made to work really well. I'm just going to move a ton of the low speed shims to the bottoms of the stack Andrew see what happens since i don't know how to design a proper stack. I'll just have to keep messing with it. Thanks again.
@MrDuhfactor
6 жыл бұрын
john Franklin Sounds like you've already looked at the big things. You are on the right path. If you want to email me the measurements of your basevalve shim stack, Im happy to take a look at what you have and offer a suggested starting stack. email to Mrduhfactor at gee mail dot com.
@Nerb1
7 жыл бұрын
Is it trial and error, or do you have a rough calculation on what you need? ie, you have gone from 11 to 20 shims... is that 1.8 times stiffer in the compression?
@MrDuhfactor
7 жыл бұрын
There is a "Shimstacker" software that you can purchase rights to use that can do a lot of calculations for you, but then one must be able to assess and determine what that numerical data means, and interpret how that will affect the "feel" of the suspension. When I revalve, it's kind of an educated guess based on experience from doing 100's of forks and shocks, and keeping all my records. For me, I'm trying to get a certain "feel" by modifying what I "don't like" about the suspension, until I get to where I can't find anything I don't like anymore, lol. On my old motocross race bikes, I would have the forks apart about 20 times until I found the perfect combination, then I wouldn't touch it...lol One can take that data though, and apply it to other similar situations, modifying it based on predicted differences, ie weight, rider speed and skill, etc, etc... Does that makes sense? Basically, it's all just a bunch of crap....lol (not really)
@MrDuhfactor
6 жыл бұрын
Nerb1 Sorry bro... I cant believe I missed this a year ago.... Im such a tard..... So, there are calculators one can use, one is called "shimstacker" that you can purchase, but depending on whether your wanting to stiffen high speed compression, or low speed, you either add # of shims, or use thicker shims to resist hydraulic flow. For me, after doing so many over the years, I pretty much can feel what I dont like about a set up, and modify the shims as needed to fix the things I dont like. For example, if my forks keep diving or bottoming when I go through a swale, or berm, Ill add a few low speed compression shims to keep the front of the bike up so it doesnt bottom out so easily.
@glendecuir6317
7 жыл бұрын
the magic of TV and mr. duh Factor....lol
@MrDuhfactor
7 жыл бұрын
The magic of stripped base valves.... lol.....
@palmpilote
7 жыл бұрын
No crossover shim in new setting? Will this induced harsh feeling when low speed riding? Just curious. :P
@MrDuhfactor
7 жыл бұрын
I considered adding a crossover, but decided against it because the 990 is so heavy, and open deserts allow such fast riding, that I worried it would still be to mushy and soft. Many tuners are going away from using 2 stage and especially 3 stage shim stacks nowadays, and I'm very happy with how plush, yet firm the forks turned out. Good question buddy :)
@MrDuhfactor
7 жыл бұрын
By the way, if your area has slower speed riding, and you worry it might be too stiff, you could always add a 16X10 or 18X10 crossover. :)
@navythomas8
7 жыл бұрын
So do you have to replace the Screw/Bolt in order to accomodate the taller stacking? and also to Mushroom the head for locking it in?
@MrDuhfactor
7 жыл бұрын
The threads are part of the base valve, so thankfully, are normally long enough, even after adding shims. The actual nut looking thing has a longer dimension that allows a thicker shim stack and still has a good number of threads connected still. Hopefully the next video will show that a little better :)
@pmoneymaster2201
2 жыл бұрын
Any chance you know the stock shim arrangement on the rebound valve? Both the check side and rebound side (or top and bottom of rebound piston)?
@MrDuhfactor
2 жыл бұрын
I can't remember bud, and have since lost the paper that I had it written down on..... Sorry my man....
@pmoneymaster2201
2 жыл бұрын
@@MrDuhfactor No worries, thanks for the speedy reply! Cartridges coming out soon. I'll just get a list once I have them out.
@89vainius
7 жыл бұрын
Awesome!! I had the forks recently refreshed, can i just flip them upside down and take out the shimstacks without opening them up completely?
@MrDuhfactor
7 жыл бұрын
Actually, I would recommend completely taking them apart again, except you don't have to separate the inner (slider) tube from the outer tube, thus not disrupting your seals. I'm always wanting to make sure everything goes back together correctly, so I follow the same system every time... good luck though bud!
@b1pig
7 жыл бұрын
... aaand my KLR has none of that. think i'm just going to change the fork oil to something a little thicker and see where that leads.
@MrDuhfactor
7 жыл бұрын
Fork emulators from racetech work very well in KLR forks, along with some progressive springs, and the ol girl would work pretty well bud...
@DearMajesty
7 жыл бұрын
How did you learn all this?!
@MrDuhfactor
7 жыл бұрын
MotoBoy lots of experience trying bro... and messing up a lot...
@DearMajesty
7 жыл бұрын
I could only wish to know as much as you. I understand the technicalities behind most of suspension design and setup, but having the tools and a garage to properly actually mess about with them is a whole other ordeal
Пікірлер: 34