I've been lurking around here for a couple months looking for the recipe to add a few ponies to the KLX250S that I bought to get my son up on two wheels. Well, I think I found it, and I like it, and I want to give my compliments to the chefs: Marcelino for his cam mod (MCM mod), and Klxster for all his hard work on the dyno trying different combo mods. They are both very insightful, helpful guys and assets to this forum. Thank you both for what you've brought to this community. Thank you Klzster for the person calls and text messages helping me pull it all together.

Like most of you, I can't leave anything stock, so here is what I'm currently running: a full FMF exhaust system (Powercore4 and Megabomb), airbox lid off, screen removed, stock filter lightly oiled, filter box crankcase breather hole opened up to 3/8", dynojet 2152 jet kit with a DJ140 main jet (waiting on 144), stock pilot jet set to 2.75 turns out, Marcelino cam mod (MCM), ACR spring removed, and my smog stuff fell off during a recent ride, so I just capped it till I can get down to the dealer and order new stuff.

These mods really woke this bike...so much that I've got my eyes open for its twin - for me to call mine.

 

Take it to the next step, 351 BB with the TM36-68 pumper carb. It becomes a whole new animal. First gear wheelies are just a snap of the throttle in both 1st and 2nd gear.

 

Yeah, I've talked with Bill, he lives a few miles from me. I'm not ready to swallow that pill, yet.

 

What's the HP/TQ on that setup?

 

If I recall correctly, it comes in right around 32 WHP on the dyno Torque, I am not sure.

 

You will. I did all the similar mods you did and although it was a huge improvement over the stock bike it's still needed a little more. The BB kit scratched that itch.

 

I wish someone had data on whether the next stockbore mod ought to be a TM36 or a set of webcams 101's.. Either way, you're replacing optimized parts (stock cams with MCM, CVK running 144/1N) with parts that you hope will give more and be worth the cost..

It's been fun being a part of your performance enhancements Scootr.. Only the 144/1N setup remains to be done to optimize your new FMF system.. I understand you wanting another KLX - Performing the mods and making these big power improvements makes the KLX endearing..

 

32HP is doable with the 351 kit - BUT, it takes full exhaust, TM36, Webcams 101's.. so about $2000.00 ! GBAUTO is currently running such a "setup"..

Bill Blue has added some porting work to make even more - about 34hp if I remember right..

To me, this turns the KLX into a low performance
KTM - moneywise..

 

I'd like to ride that once.

The klx is such a nice little bike. I couldn't get rid of mine when I replaced it. Had plenty of offers but I wanted to keep it. Run too nice!

 

Installed the 144/1N last night and took it for a test ride. I was able to display 96 mph with stock gears, slight tailwind, and my head tucked. I weigh 200lbs and it would only do about 80 mph stock. I didn't buy it to set speed records, but I think this is a good indicator of the power added. She starts up very easy (MCM with ACR spring removed) and pulls very nice all the way to redline. Throttle response is snappy and well defined. Not a bad mod(s) for only $500 invested.