Ideal weight for stock 07'yz 250 springs.
Posted 20 May 2008 - 10:09 AM
Posted 20 May 2008 - 11:28 AM
See http://www.mx-tech.c...pring_generator to enter the data you are interested getting results for.
Do note that the stock rates given here are for the '08 YZ250. The '06 & '07 stock spring rates are 0.42 kg/mm & 4.8 kg/mm, according to the Yamaha Parts information.
So, for enduro type riding, the stock suspension is just right for someone who weighs 195 lbs., with their gear on.
I'm going to ask Jeremy if we also need to factor in all of the extra 'bike protection' we tend to bolt up to a bike ridden in the woods, etc. I'm talking to him soon, anyway.
Posted 20 May 2008 - 12:45 PM
Posted 20 May 2008 - 01:24 PM
Posted 20 May 2008 - 02:03 PM
As SpDyKen said, the type of riding is going to play a big part in how stiff you want the springs. A properly sprung for Motocross bike can beat the living hell out of you on an all day ride.
Posted 20 May 2008 - 02:34 PM
Im very, VERY happy with the fork right now and we are only on our second internal change.. Still have a couple ideas I want to discuss with Mitch, my tuner..
The shock is unfortunately being out performed by the fork now.. The fork action is very compliant with rolling and square edge bumps where the shock feels pretty too slow and a little harsh.. But as I soften up comp and speed up rebound to compliment the fork I have bottoming and deflection issues.. Our idea is that hopefully the stiffer spring and softer valving in rear will help carry the rear end higher and defend bottoming while remaining plush.. Time will tell..
BTW Im also running 18" rear and 20" front.. Really takes the edge off
Posted 20 May 2008 - 03:11 PM
I weigh 150, maybe 160 or so with gear.. I went to .440 in the front and am investing in a 5.0 or 5.1 for the rear.. Primarily for desert and woods.. Very little moto....
I just checked my '06 YZ250 manuals; they say that the 4.9 is the standard spring, as well. I'd sure like to know what the truth is. I'll be talking to Jeremy tomorrow; I'll be sure to ask him about this.
It makes it hard to buy take-off springs, if you cannot trust the parts listings for the different YZ's.
Anyone out there know more about this issue?
Posted 20 May 2008 - 03:30 PM
The rear spring went from a 4.8 in 2005 to a 4.9 in 2006. The fork spring got slightly softer in the same time period. 2005 was a .43 to a .42.
The problem the tolerances of the spring can be off quite a bit from the rating. If MX tech or Race tech tested the oem springs they might be off quite a bit from the service manual.
Posted 20 May 2008 - 04:24 PM