I did the KLX needle, uni filter, rejet, FMF Q4, de-snorkel, slide drilling, etc. How much actual increase in performance is netted from these changes is debatable, and with the relatiively expensive exhaust, $/hp or $/ft-lb its not a lot of bang for the buck on paper. That being said, my bike will now wheelie in 1st easily, and with a fair amout of clutch abuse can be hoisted up in 2nd. Major improvement in throttle response and general rideability and it sounds good without being loud. Money well spent? Perhaps not, but if i bought another KLR i would do the same mods to it too.
Moab rear shock & Progressive front springs: Expensive but worth every penny to me. If you have spent years riding MX bikes and sport bikes with actual competent suspension, the KLR's boingers just dont cut it.
Pro Taper Evo's: Taper section bars are the bomb. Seriously, i had no idea how much difference they can make in how a bike feels in terms of feedback thru the bars. A friend had them on his MX bike and raved about them. I decided to try some on his reccomendation and have been hooked ever since. I will not own an offroad bike without them. They seem to damp vibrations better, and if you crash hard enough to bend or break them, its probably not a crash you are going to walk away from, they are hell for stout.
Fork Brace - Steel brake line: Brake line improved front braking by maybe 10%, but every little bit helps. Fork brace benefits are arguable, but it looks cool and I have convinced myself that it adds something useful, so in my make believe world, its an awesome upgrade.
I guess I could have ridden my KLR in stock form, but to me its a lot more fun with the upgrades i have made. 20 more HP would be nice, but seeing as its not up for sale, i must be pretty happy with what its got now.
A friend of mine asked me why I use a $1000+ .375 H&H mag instead of a 250$ Wal-mart .30-06 when the only things i hunt are deer and feral hogs. My answer is that my rifle is more interesting, more fun, has more capability, is a challenge to shoot well with the recoil, and to me, its just more "cool". I guess its like the KLR, I just like to blow $$$ on cool stuff for no damn good reason.
2008 B-King - Bone stock
2007 KLR650 - Moab shock - Progressive springs 10wt oil - Happy Trails fork brace - Steel front brake line - ProTaper Evo - Acerbis Rally Pro guards - Uni Filter - KLX needle - De-Snorkled - Slide drilled - FMF Q4 - DooHickey done - Swingarm pivots drilled/tapped for grease Zerks - Custom (homebuilt) mount and Pelican 1450's.