[KLX 300 FREAK]

I own a klx 300, i have put a new fmf q series pipe on, new air filter, and jet kit, but it still lacks good power. I have heard that if i change the carb < keihin cvk>, to a better model say a mikuni slide carb it mades a world of difference. My real question, is has anyone else found this problem, and tried this solution? If so is it really worth it? and if so, what carb did they change to?

I have also looked into big bore kits, and the best i could find is from Thumperracing.com in texas, they have a kit that bores it out to 377cc, but with cyclinder boring, and the kit runs about a grand, minus dismantling the engine, whiich to be honest i don't feel comfortable doing myself, so i would have to spend prolly another 500ish for a mechanic to rip it apart then put it back when the new kit arrives, so for me i think i will skip big bore till later. I was hoping to do everything i could reasonably do that was easy or close to bolt on to realistillically improve the performance. :wink:

 

[1Adam12]

Flatside carbs will improve your response for the bike - pulling more power would require you to go a larger carb. Remember that more power is produced by a free flowing air source (air filter less restrictive) open pipe (exhaust flows free) and adding more fuel (jet kit) or larger carb.

Another way to pull more power out of your bike is to have the engine blueprinted and talking to an engine builder.

When you say lacks good power have you dialed in your pilot screw settings on the carb? If so then one of the ways to pull more power is going to a larger carb and you mentioned a better responding flatside carb.

Wiseco has two piston sizes 78mm and 80mm

http://www.wiseco.com/

I think it would be cheaper to put your money into a bigger displacement bike though.

 

[KLX 300 FREAK]

I have read at another post that replacing the stock cvk carb with fcr pumper carb is the way to go, but dang that is is pricey, all i want is to be able to pull 4th gear going up hills instead of bogging out i have new pipe with jet kit, and new uni filter. And don't mind really spending the cash for carb, but i don't want to if it really doesn't help.
here is the website for the guy that claims new carb, header pipe and vent kit makes about 5hp more for it
fourstrokeworks.com his name is jerry, i talk to him on the phone he does engine mods, susp. etc.
But he recommends a FCR pumper carb < at 675$>, new header< 160$>, jet kit< 50$>, vent kit< 50$>, to make it happen.
But i have heard from couple other posts that if i change to a mikuni 36mm pumper carb for about 300ish$, it does the same thing.
My real dilema is there anyone out there that has tried either? if so is it worth it??
Because i am not gonna be able to buy a new bike, this one is financed as is, and won;t be paid for till maybe next year, so for now i just want to improve what i can, but not if the gains don't justify the expense.

 

[QKENUF4U]

just change out the sprockets/chain and enjoy 4th gear hill climbs. fastest,easiest,cheapest way to go.
good luck

 

[1Adam12]

Ok - since the new bike for the new bike is out, then I would say it sounds more like you need some tunning since you are bogging down. Is it a specific rpm that you are having problem with??? Sometimes you will hit a flatspot that can be made better or corrected without laying out a ton of cash.

1. Play around with your pilot screw a little and adjust from where it is now to a 1/4 turn leaner and see how it rides. Notate the current position and where you move it to and see if you can track down at what rpm you are having problems.

2. Changing sprockets can get you to ride out of the flatspot by riding at higher rpms if you drop 1 at the front sprocket or messing with the rear sprocket.

3. Going to a larger carb will help blow more fuel in, but will still need to be tuned by either a pro or take some time with the settings getting it dialed in to ride the way you want it to.