A mechanical issue required me to replace the OEM shock spring on my 17 KTM 450 SX-F. The stock spring was a 4.6 kg/mm and I replaced it with a 4.9 kg/mm. The 4.9 is the next step up on the stiffness
The 4.6 worked fine but was at the limit with pre-load for my weight and riding style/skill/speed. I weigh 200 lbs and the 4.6 is said to be good up to a 189# rider.
I'm a 57 year old who'd been riding MX for 45 years. I weigh 198 naked and ride at an intermediate vet pace.
After installing the new 4.9 spring and setting sag at 105. I've ridden the bike twice since and have the rear shock dialed in.
Problem is the forks are now beating the hell out of me. They were PERFECT prior to installing the new rear spring. I've been running 135 lbs in the forks since buying about 1.5 years ago with 22 clicks out on the comp. LOVED the forks.
However, now the forks are just terrible. So harsh the outside palms of my hands hurt to touch after riding all day yesterday on a somewhat rough track. I progressively backed the compression out all the way (i.e., 36 clicks) and no better. I reduced air to 130 pounds and not really any difference. I have Motion Pro bleeders and vent/release outside chamber air pressure every time I go on track. I have not had ANY increase in air pressure since the problem developed.
Anybody have any thoughts on what might be the issue. Keep in mind the ONLY variable to the bike is the different, stiffer rear spring. This is NOT a subtle feel change, it's harsh as hell. Funny as it turned better and held ruts better but everywhere else it hurt....
TIA
Rick