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Hey guys I have a 2003 crf230f, and Im looking to get a better response out of it. I put in the upgrade jetting kit, and removed the airbox snorkel and the baffle from the muffler. Ive heard of some people putting a 11:1 piston in it, but Im wondering if its too high of a compression for my engine head. I know its not a 250r, but I would like a bit more power and response. would appreciate any advice you could give me

Hi jwtex and welcome to the site.
With the mods you have done it should have woken the bike up a quite a bit.
Do you know what needle, main and idle jets you have installed?

I hope you kept your original needle and jets and if so what are they as well.
The early needle is actually pretty good.
Yes I run the Honda "power up" needle which works ok but we have different fuel in Australia.
It works for the rpm I ride at and my riding style.

How does it go at low speed, mid range and top end.
Is there something specific that you feel should be better?

You still may have to adjust fuel screw and do some jetting changes to get the best.

What elevation and temperatures do you ride in.

When you removed the snorkel did you leave the bit of rubber that runs around the hole you left.
I feel leaving it is better than having a sharp edge for the air to flow over.
Also gives a little extra protection when creek crossing.

Due to the age of your bike I don't feel going to a 11:1 piston would give you that much benefit on it's own.
To get the best out of it you would need a cam change and some head work.
Depending on engine condition you may end up rebuilding more than intended.
The stock exhaust though heavy actually flows well and changing it is not worth the expense.
keep your baffle and snorkel as baffle can be drilled and reinstalled for a quieter ride that still flows pretty well.
Keep the spark arrestor installed.

Some of the smaller cams could prove a good bang for buck upgrade but lets make sure the jetting is dialled in to it's best first.

Hey thanks for your reply! Im running the Honda power-up kit on my bike, and the sprocket ratio is 14:48. I did leave the rubber seal on the airbox. The low end isnt bad, but mid range to top end is next to no power. Im looking for more growl for the bike, and a faster response out of the throttle. I dont want to have to wind up the rpms in order to lift my front tire over a log. And I didnt get rid of the stock jets, which are: main jet is a 102, and the pilot is a 42. I am running a 135 main with a 45 pilot

Hi jwtex,

You didn't say what elevation or temperature you ride in. This will make a difference to the jetting.
Do you do desert riding or more trail riding as you gearing is 12% taller than stock (13/50) and will cut down your acceleration?
Good for cruising desert though, not good for trail/woods riding and will make it harder to lift the front wheel.

What clip position did you use on the new needle? As the clip gets closer to the bottom the richer it will be from 1/4 to 3/4 throttle.
I will take a guess here about your riding conditions at the moment and say you are running rich towards the top end.
I run my needle at the third/middle clip position, there should be 5 cuts into the needle.
I would also drop to the 132 main. I have had to use a 128 main in summer when hot AND humid.

Have you adjusted the fuel screw for a good idle and how many turns out from gently seated is it set.
Once set you can try an extra 1/4 of a turn out to see if them helps off the line, as long as it doesn't foul the plug.
Remember these carbs don't have an accelerator pump.

Alternately some bikes don't like the extra fuelling of the power up setup.
I assume that is different fuel in different countries and the humidity does play its part as well.
Humid weather means your engine sucks a bit less oxygen and needs a bit less fuel.

If you trying dropping the main jet and the clip is right you have an alternative if it doesn't pull middle to top.

If you have a C39A needle as an original it can be paired with a 120 Main for sea level to 1000ft use.
Different elevations may need a different main jet.
I would still use the 45 idle jet at this stage though some went to a 48.

Hope that helps

We are at 920 feet above sea level, and my clip is in the middle position. I do more road riding, but I also ride off road almost as much. My fuel screw is turned out 2 turns, and feels pretty good there. Also I have a question..... If I put an Xr250r carb in my bike, would that help with my throttle response? Ive heard that since they have accelerator pumps, they help a lot with response. I really appreciate your help!

Well the XR250 carb can be made to fit the biggest problem is getting the fuel inlet not pointing at the frame so you can get the hose on, or so I am told.

Would be good for mid to top end but you will loose bottom end pulling power.
Since you are geared for road you might notice this more.
The tractor like pull at low speed is one of the 230 positive qualities.

Apparently the XR needle from 1996-2004 seems to work best.

This carby change is generally done with well modified bikes (Cams, heads etc) so unless you already have a new or rebuilt carb it may be a costly experiment on a stock bike.

If you go ahead with it be sure and post it up here so people know what works.

My goes about 50 mph comfortably though is bit hairy on bumpy dirt.
They weren't designed to be road bikes you have to remember.