[Rezzy]

Hey Guys, I have a 2003 CRF230f that I uncorked so far by changing the jets, removing the airbox snorkel and lining and removing the baffle. Now I am a complete newbie to uncorking and pretty much bikes in general but after doing plenty research and following directions carefully, I decided to give it a try. I removed the carb, cleaned it changed the jets, snd moved the needle down to 4th position. Now this is only like my 2nd time ever removing and opening a carb at all but everything seems to go pretty good. I then removed the lining and cover for the airbox and attempted to remove the baffle. The small screw that is supposed to allow the baffle to be removed is very stripped so until I can remove that I just took off the entire spark arrestor and baffle just for now to see if it will run, turn on etc. but I wont ride it like this.

Anyhow, I reinstalled the carb and the bike would turn on but not idle, just died right after letting throttle go. I adjusted the idle screw thinking I might have messed with it by mistake or something, and it worked, it was idling everything seemed good. Then I noticed the header pipe on the exhaust was hotter than usual because it smelled like soemthing was burning a little and I noticed some steam coming from it. Now i know these pipes are supposed to be very hot but this seemed way too hot I figured it had something to do with changing the jets but the pipe seems way too hot and the smell and steam doesnt seem right.I checked for any air leaks on the carb seals and refastened them but still the pipe gets insanely hot after a few seconds of being turned on. If anyone has any advice or can tell me how to deal with it please let me know. As I said I'm very much a newbie but feel like the carb cleaning and jet changing went well. I used a 120 Main and 45 pilot jet (I'm at sea level), I kept the needle because it's a 2003, and just moved it down to 4th position from 3rd. I did notice my fuel screw did not have an O-ring and washer so I got a replacement for that that I will put in today. Also I checked the spark plug after rejetting and turning it on a few times and there was a lot of carbon build up , last time i checked a couple weeks ago before uncorking it looked fine. Well somebody please let me know if you have any suggestions I would appreciate it, Thanks!

[Aussiecrf230]

Hi Rezzy and welcome to the site.
Make sure the washer and o ring are not stuck up inside the carb body. If it is actually missing then this is the first thing to remedy.

The jetting sounds about right for standard needle and I assume this heating you have noticed is at idle, so fixing the above will definitely help.
How many turns out is your fuel screw at present. Once an o ring is installed you will have to adjust. If you have to go out more then 3 turns from gently seated then you might need a 48 pilot jet. Some 230s run OK on the 45 some prefer the 48, it is just how it is with every bike being slightly different.

A new spark plug wouldn't go astray either and will make it easier to tune. Ensure it is gapped correctly 0.8-0.9mm (.030-.040 inch).

[Rezzy]

Hi Rezzy and welcome to the site.
Make sure the washer and o ring are not stuck up inside the carb body. If it is actually missing then this is the first thing to remedy.

The jetting sounds about right for standard needle and I assume this heating you have noticed is at idle, so fixing the above will definitely help.
How many turns out is your fuel screw at present. Once an o ring is installed you will have to adjust. If you have to go out more then 3 turns from gently seated then you might need a 48 pilot jet. Some 230s run OK on the 45 some prefer the 48, it is just how it is with every bike being slightly different.

A new spark plug wouldn't go astray either and will make it easier to tune. Ensure it is gapped correctly 0.8-0.9mm (.030-.040 inch).

Hey Aussie thanks for the reply. As for the washer and o ring i read from many different sources that it gets stuck up there so i thought that was where mine were. After trying to get them unstuck with a bunch of different small tools, I realIzed there wasn't anything in there lol. I'm not sure if they fell out when i took the screw it out while cleaning the carb but I'm pretty sure they just were never in there. Anyway i got the replacement and i'm going to change the fuel screw with a replacement oem one that came with washer and o ring as well as change the spark plug. I'm forgot exactly how many turns the screw was because i messed around with after just a little while the bike was running, but I'm pretty sure it was around 1.5 - 2 turns out after lightly bottoming. So are you saying you think the pipe getting that hot has to do with the fuel screw?

[Aussiecrf230]

The longer CRFs Only Fuel Screw is easier to adjust especially when engine is hot. If you use a standard fuel screw you can get a long right angle screw driver that will make it easier. A lot of bike mechanics have them so they must be available.

With the o ring missing the mixture would be lean, so replacement should fix the problem.

Post your results after you change it.
I would start with fuel screw 2 turns out and adjust from there.

[Rezzy]

Hey so I put in a new spark plug and installed a new fuel screw with new washer and o ring. I turned the screw about 2 turns out and started the bike. It ran good and the header pipe didnt seem to get hot as quick but after a few more seconds it was really hot again, there is no steaming but i still get a weird smell when its really hot. Also i still have the complete baffle and spark arrestor removed because the screw to remove the baffle is really messed up, I am going to take it to someone tomorrow to see if it can be removed. Besides that the pipe still gets pretty hot, I'm just got sure how hot is normal anymore. I might just bring it somewhere, any other suggestions though, and how hot does your pipe get?

[Aussiecrf230]

Have you adjusted the fuel screw till you got a peak in the idle speed? At this point it should be a good mixture setting. If so, how many turns out did you end up being? Have you driven the bike to see how it runs especially from slow to fast revs. Remember you just need to roll the throttle open rather than snap it open. The do get hot and will leave a nasty burn if you lean your skin against it. You only need a greasy finger print on the header to get smoke and a burnt smell until it is gone. If it doesn't glow a dull red it must be close to being right.

[Rezzy]

Hey Aussie and everyone else! So just to update on things I put in a new spark plug and the fuel screw.. I didn't adjust the fuel screw while the bike was on, when I installed it I left it 2 turns out and it sounded good idling. I made a very minor adjustment to the idle screw though just a tad to get a slower idle but I'm not sure if this was even needed. I finally got someone to remove that stubborn screw on the exhaust end so i could take the baffle out. I reinstalled the spark arrestor without the baffle and took the bike for a spin. The bike doesn't sound great without the baffle but I can live with it. The header pipe and exhaust itself do get pretty hot still and pretty quickly but to be honest I'm not sure how hot they were getting prior to all this. I have not seen any more smoke though so that's good. When riding it does feel a smoother and there's more response on the lower rpm's. Only thing I noticed, that was also happening before i tampered with the bike, was when I snap the throttle in neutral and or while riding in first gear, I sometimes get no response or a lag in response however you call it. I noticed this before I did anything to the bike when I was seeing if i could clutch up some little wheelies in first. Sometimes it would rev nicely other times it cuts out. I've heard about it being related to the carb and all that but after all the mods and cleaning it should have cleared out right? Anyway thanks for reading this and if you have anymore insight or could tell me which things are normal that I'm experiencing I would appreciate it. Thanks Again!

[Aussiecrf230]

You can't snap open the throttle on a bike whose carby has no accelerator pump like the 230. From idle it will often stumble and not rev. You need to roll the throttle on as quick as it will allow. If the idle mixture is still out it will be worse.
It still may need the fuel screw adjusted out further (no more than 3 turns) or indeed go to the 48 idle jet (if more the 3 turns required) and start the adjustment procedure again. You need to adjust the fuel screw when warmed up and idling till the RPMs peak. You then adjust your idle speed screw if it is too high.

As far as how hot the exhaust gets - hot enough to melt your nylons or you boots. It is only single skin so is same temperature the piston sees when the mixture burns.

[Aussiecrf230]

So Rezzy how did you go?