F a ex and it's cold starting crap, RANT :/

[Thumpin440ex]

I swear to god I truly hate this bike in anything under 50 deg's. It is a non starting SOB. All it wants to do is backfire out the pipe. Anything over 50 it is a true gem, starts with a pump or 2 of the throttle, runs flawless. I need to figure out a way to hook the choke up with this 450 carb, because no matter what I try it just doesn't start in the cold. It has been like this from day one waaaaaay back in 2000 when it was stone stock. Cold hearted POS. I really shouldn't bish like this being 30 y/o and all but holy sheet.


John

[ish416]

My EX is the same way, 45 and under it does not want to start. Anything above that, a few taps of the throttle and it fires right up.

Since I bought mine new in Feb of 99 it's always been this way.

[HondaRacing83]

mine starts pretty good all the time actually lol. always has. 42pilot helped alot lol. sometimes it takes a bit chokin it

[DragonGunner]

So its a 450 carb an not the stock correct.....? Either way you are way lean...if 450 carb go to a 52 pilot, also you can raise the needle a notch, not sure what fuel you running but usually the higher the octane the harder to ignite, sometime thats just the way it is with gas, not much you can do there. Try a splitfire sparkplug 416 is the Number. Also in colder weather thinner oil will allow it to crank an start easier too. An last if your battery is several yrs old its just not putting out like it use to...often I would throw a charger on, put on boost an it would take right off.....hope some of this will help.


also air mixture screw adjustment just a little can make a big differance also, cut back on the air an richen a little.


Oh! you have a sparks CDI....theres the problem also...I have a WB CDI an when it gets down to 30 an below, I have to put the stock cdi in, starts right up.

[DragonGunner]

Originally posted by HondaRacing83
mine starts pretty good all the time actually lol. always has. 42pilot helped alot lol. sometimes it takes a bit chokin it


When I did that with my 99' it started SOOOO much better cold...in fact I took the choke out yrs. ago....stab the throttle a few times an starts right up....sometime when real cold I'll have to do that a few times...but no choke so thats expected.

[Thumpin440ex]

I know that some are better then others with this. I have a 50 or 52 pilot in, should be plenty of jet. Note I have the 450 carb. Just gets annoying.


John

[Baileygunns]

It's that CDI box... Swap a stock one in.
Last season my buddy had the same issue with a 426, 450r carb, cammed, piped, ported.. Stood there in the yard trying to get it to start and idle. I walked into the shop grabbed a stock CDI off the shelf, plugged it in and issues were gone. Never took the stock CDI box out again.

Bike started every time and idled mint and the ONLY change was the CDI.

[Thumpin440ex]

I have often thought of that, but the bike did the same exact thing STONE stock. I will try to find my stock one, see if it helps, but I can not see it solving the issue. But I have been wrong in the past.

[Baileygunns]

It's the spark curve in it... It makes it a hard start. Give it a try and post back.

I think I have a couple WB boxes somewhere on the shelf and I will be putting the stock one in my wife's build with out a doubt.

[CJM]

Have both the WB and the stocker, it starts fine with 52 pilot and stock cdi. Little harder with the WB, but I crank the idle up anyways.

Did ya try cranking the idle up? I usually stab the throttle 3-4x, crank the idle up and hit the button. When its warmer out it jumps to life instantly.

[Thumpin440ex]

I havn't turned the idle up and tried, but I generally have the idle high cuz i always forget to idle it back down. I will give that a shot tom, if I can find the stock box i will try that also. I think my bike is just blessed with evil, it has been like this stone stock from day one. I use to have and let the shop heater blow on it to warm the jug up back in z day


John

[Stickman400]

I have my 400 stored in a heated shop that is around 70 or 75 year round, and in the the summer (65+ outside) it fires up instantly with 2 pumps of the throttle (450 carb, 55 pilot) Now the other day I went out and tried to start it when it was about 55 OUTSIDE, inside the shop it was still 70+, and it took FOREVER to get it to start, had to pump the chite out of the throttle several times. Idk if it's because the jetting is a tad rich and the time of the year or what but it is very annoying. I had a piece of bailing wire rigged up on the carb for the choke that worked but since I never used it this summer I took it off. I may just have to rig up something alittle better this winter and leave it be.

[Thumpin440ex]

Yah man it is surly a pita, thats for sure. I wish the kicker conversion was easier. It seems if it has a little more snap to the starter it might go..


John

[CJM]

What battery are you guys using btw? I got the busa battery in mine and like it alot better, cranks over way easier overall.

[Stickman400]

I got the same one you do Marc. I had you give me the part number and where you bought yours from awhile back if you remember.

[CJM]

Ah that you did if I recall.

IDK, mine spins over ok when cold. Kinda a pain to start with the WB CDI, stocker gave me no problems tho.

[NacsMXer]

It's likely hard to start when its cold out because you had its ideal jetting set for warmer temperatures.

Try adjusting the pilot screw a little richer. If that doesn't work, go up one size on the pilot and fine tune the pilot screw till you find the highest idle and best response.

The pilot screw fine tunes the starting/idle circuit after all. My quad was acting the same the other day trying to start it, then I realized I had the pilot screw on the FCR set when it was 75 degrees out. I gave it like a half turn richer on the pilot screw, and now it fires up in within a single revolution of the motor.

[Thumpin440ex]

I also have the zuki batt. I am going to mess with the pilot a few turns, see if that helps. No doubt the jetting is prob out due to the weather change. But I am not gonna do the whole rejet thing just because it gets cold, then rejet when warm. I will live with getting a pop start, hahaha.


John

[duneslider]

You shouldn't have to do the whole rejet thing everytime it gets cold. Once you get it figured out you just have to make the same change each time.

It gets cold enough here that I have to do a jet or two bigger in the winter and some minor tweaks to pilot and thats about it. Takes just a few minutes and I do it once the temp hits 40's.

[Mtndew99]

Today I just got my front end all back together with yfz brakes on it and decided to see if I could do a stoppie in the drive way well it's about 35 degrees here and I just turn on the choke and gave a pump of gas and it took maybe a few tries but it started after sitting for 2 weeks then I shut the choke off and I have a xr250 cdi but I think it all depends on jetting and mods

[MtnEX]

Another thing that is overlooked is decompression and starting compression... and starter strength.

They will be very hard to start cold if any of these are a problem.


Me personally, mine will start fine... then die... lol.

Does it several times over and takes it a good while to get where it will take any throttle. Just how it is. Colder it is, the worse it is.

On mine though I think it is lack of compression. There was a good bit of difference between hot and cold compression numbers.