Fresh rebuild, problems starting

[greenlantern99]

Hi, all. New here. But not new to EXs. Had a '99, and sold it about 3 years ago. Upon finding a frame for $140 on eBay in mid May of this year, I got a wild hair and decided to build an EX from scratch, buying all my parts off line. 05 Reverse motor, 99 frame and subframe, 02 swing arm, stock rear shock, 450r front shocks, tusk +4 rear axle, full flight +2+1 a arms, stock hubs all around, niche carrier, new swing arm bearings, new front hub bearings, namura 440 kit (jug and piston), stage 2 hotcam, gt thunder head studs, stock carb waiting to be jetted with dynojets, pro design kill switch, some used aftermarket bars with center brace, maxxis razr mx 20x6x10 front 20x11x10 rear mounted on stock looking Itp wheels. Powder coated frame, sub frame, swing arm, and a arms black. Red 99-04 plastics. Blah blah blah whatever

So I finally get to where it SHOULD have started today. I hooked the gas up, pumped the throttle a few times, and started winding on the starter by jumping the relay. My starter button wasn't working. It never fired but I could smell gas from the carb so I figured it was a wiring gremlin somewhere keeping it from getting spark. I go inside and look at several diagrams and finally find out that the ignition switch I am using is from a 99-04, which has 4 wires but utilizes a 3 pin connector and a single connector for the 4th wire. I have an 05 wiring harness which does have a 3 pin connector, but not for the ignition switch. I mistakenly had the two hooked up together which was why I wasn't getting fire and why my starter button wasn't working. 05 and up used a 4 pin connector. Instead of waiting another week for an 05 and up switch, I cut the pig tails off the harness and switch and wired them together temporarily. When I came back out to the garage to do my wiring, my garage floor was soaked in gas. Carb had leaked all the contents through the longest (I'm assuming overflow tube?) tube coming out of the carb. Got the gas up, disconnected the tank from the carb, turned the key, hit the button. It was winding but I still wasn't getting anything, I was assuming it was flooded until I heard it backfire once. Sounds like a timing issue but I guess it could be a fueling issue as well. Also, while winding on the starter, if I pump the throttle any at all it bogs down really bad and the starter doesn't even want to turn it. What do you guys think?

[DragonGunner]

Carb is leaking from a stuck float, or got grit in the float needle spot so it needs cleaned and inspected….or your overflow screw isn't turned all the way in…someone may of loosened it to drain gas before removing it. Other starter cause is weak battery, usually when mine won't start and I stab the throttle and it stops its the battery being weak. Remember you can pull your plug, if its dry its not getting gas…if you been pumping it….if wet its getting gas but like you said you may of flooded it.

[mtsnieg]

C'mon man, if it's leakin gas out the carb, what do ya think it is? If ya built this thing from the ground up like ya said ya did yas should know how to diagnose a fuel leak like ya have!!

[greenlantern99]

C'mon man, if it's leakin gas out the carb, what do ya think it is? If ya built this thing from the ground up like ya said ya did yas should know how to diagnose a fuel leak like ya have!!

I obviously know why the carb is filling up and leaking. What I really want to figure out here is why it bogs down like it does when I push the throttle when starting. I eventually ran my battery down but when i was cranking on it, the battery was fine. It's brand new, just hooked it up the other day. It was turning just fine until I hit the throttle. When I hit the throttle, it sounded just like something grabbed the crank to try to stop it from spinning

[KKiowaTJ]

No reason to push the throttle while trying to start. If anything I turn gas on, give it two thumbs of throttle, turn gas off, then try to start. For reason of flooding. It will give you more than enough each time to get it to pop off. Choke helps, but still no reason to add more via thumb.
IMO I'd get back on and buy the correct harness so you know everything is correct and not cut and hacked. Fuel problem mentioned, fix mentioned. Plus if it is not jetted correctly for the 440 kit, it's only going to sputter if that. Needs more air and fuel now, not later on. Good luck either way

[greenlantern99]

No reason to push the throttle while trying to start. If anything I turn gas on, give it two thumbs of throttle, turn gas off, then try to start. For reason of flooding. It will give you more than enough each time to get it to pop off. Choke helps, but still no reason to add more via thumb.
IMO I'd get back on and buy the correct harness so you know everything is correct and not cut and hacked. Fuel problem mentioned, fix mentioned. Plus if it is not jetted correctly for the 440 kit, it's only going to sputter if that. Needs more air and fuel now, not later on. Good luck either way

It has the correct harness. 05 motor, 05 harness. The reason the connectors weren't the same is because the ignition switch was 99-04. Haven't considered jetting, good idea. I was thinking it would at least run on stock jets so I could see how it was burning and what it needed. Thanks!

[KKiowaTJ]

My fault! Re read and all the years threw me off lol!

When ya said had 99', then bought 05' motor, then back to 99' chassis and sub lmao! I would clean the carb out real good and bump the Jets up to what another with a similar set up has, or the recommended size for a 440 kit and go from there. A choke delete and 42 pilot wouldn't be a bad idea or leave choke if that's your preference.

[greenlantern99]

My fault! Re read and all the years threw me off lol!

When ya said had 99', then bought 05' motor, then back to 99' chassis and sub lmao! I would clean the carb out real good and bump the Jets up to what another with a similar set up has, or the recommended size for a 440 kit and go from there. A choke delete and 42 pilot wouldn't be a bad idea or leave choke if that's your preference.

What are the benefits of a choke delete? Never heard of that being done before.

[greenlantern99]

It now runs. Turns out my kill switch was faulty so I wasn't getting spark.

It's running super hot. I'm assuming most of it is from running lean since I'm still on stock jets but something else is not right. Within literally 10-15 seconds of "running", I can pour water on the exaust and it'll sizzle like it would on one that's been running for 3 hours. My clutch cable even melted a little from touching the part of the exaust behind where the heat shield is and It hasn't ran for more than 30 seconds. Clutch also doesn't want to work. Won't lift.

[KKiowaTJ]

If you add a 40-42 pilot jet, couple plunges of the thumb -10/96° don't matter she will fire right up, so I have read and no person who has done it responded with bad results. Maybe a couple super cold and nothings starting, but rare!

I assumed you fixed the spark all together. I'd start with correct jetting or a lot closer than it is. Fuel cools the motor too and it's lacking bad! That's where I'd start, has to be in closest running shape to diagnose and a 440 kit changes the game alot. It's gonna run hot, thinned out! But tanks and other things can be done.
But to do that, has to be with in reason to the build and parts on it. Then a cheap heat gun will give ya quick results along with a couple new plugs for color. Plus if the temp is warm, it's gonna run hot and the melting is the main flaw and a 250x clutch cable is longer and can be routed down chassis away from motor. But look up and go to the rich end imo and work back. Plugs are cheaper that a melt down lol.
Plus with all the $$ ya threw at it, a FCR card might be a better deal all around! Curtis sparks iirc and or 450r card and adapter boot. A 400 carb can be done, but with all mods done, what a couple hundred extra to have a top of line carb to match quad in performance and reliability!

I'm in same boat kinda, have all new to put on, chassis, sub and swinger are going to be only oem parts, holding off for carb and rebuild. But I'm liking my current set up less my bald tires! But winter and all coming , I'll hold off until early spring like I keep saying lol.

[JOHNDOE83]

My 440ex used a 220 main jet and a 50 pilot jet with a 450r carb and used a 42 pilot and a 200 main jet for the stock carb.

Jett it right to get max performance out of your 440, in my opinion a 190 is minimum for a 440.

Thin walls are a myth, if its running hot its to lean my 440 ran constant 200 temps after hard running.

You dont need oil coolers and all that fancy stuff unless your doing desert racing.

[greenlantern99]

What mods did you have and what brand jets did you use, if you don't mind me asking?

Edit: forgot to mention that my 42 pilot has been ordered for a couple days now

[JOHNDOE83]

What mods did you have and what brand jets did you use, if you don't mind me asking?

Edit: forgot to mention that my 42 pilot has been ordered for a couple days now


440 with stage 2 hotcam, +2 valves, 42mm 450r carb, no airbox, stock header with modified/hollowed out white bros shorty slip on, white bros rev box.

used real Keihin jets

[greenlantern99]

440 with stage 2 hotcam, +2 valves, 42mm 450r carb, no airbox, stock header with modified/hollowed out white bros shorty slip on, white bros rev box.

used real Keihin jets

I have a stage 2 hot cam, no air box lid, k&n filter, stock header, and hmf slip on. Should I even bother going any lower than 200 main?

[JOHNDOE83]

I have a stage 2 hot cam, no air box lid, k&n filter, stock header, and hmf slip on. Should I even bother going any lower than 200 main?



I have a stage 2 hot cam, no air box lid, k&n filter, stock header, and hmf slip on. Should I even bother going any lower than 200 main?


generally people would buy a dyno jet kit, in that kit theres a 175 dyno jet main jet. Which is equivalent to a kehin 190 and is widely used as a common jet kit for stock bore all the way to big bore + mods.

It depends on how much you wanna spend, jets arent much money but consider that you might need bigger jets or extra jets one day for who knows what.

Id get 220-190 in incriments of 5 just for the hell of it, start at 215 and if it sputters out at wide open throttle, if not take it for a ride and see how it does.

You dont need actual kehin you can buy oem equivalent and be fine.

scroll half way down to the jetting procedure section in the link and look for #4 main jet tunning.

good site to get your jets from to.

http://www.jetsrus.com/FAQs/FAQ_rejetting_101_how_to_rejet.htm

[greenlantern99]

Got the 42 pilot jet in and it idles great. Still seems to heat up too fast. Maybe it's just me. Went with the highest dynojet jet I had, which was a 170. I ordered 210, 215, and 220 keihin jets from that site, thanks for posting it. It's a shame I couldn't use the ones from the dynojet kit. More wasted money. Anyone know if I could use/receive any benefit from using the DJ needle?

Clutch still won't lift. I know I have the actuator arm in the correct position. Grooved basket maybe?

Edit: clutch works

[JOHNDOE83]

cool i hope it works out, make sure to update us on the outcome.