please help 450r cutting out

[Houser450]

ok ive got this 06 450r converted to a kicker that if you stab the throttle it will cut out it seems like a electrical issue to me but im not positive here is a list of what i have done
changed
jets, carbs, filters, pipes, cams, adjusted valves, changed stator cdi, coil, voltage regulator, unplugged tps, overided the throttle safety, new gas, new oil, changed rider, no ripped or loose intake boots, cleaned grounds up.

any other ideas? i cant figure this thing out help please!!

[Snoopy450r]

sell it and buy a another one, should do the trick.

[Houser450]

yah i got a buddy that races them i think he needs a spare parts bike

[Jerryz450]

Check the ground wire for the cdi
Mine was very loose / almost broken at connector
Also Check all wires for the tether. If they were cut, altered, spliced,

We need to go race or ride again.
2 wheels or 4

[Houser450]

still no luck could it be something in the topend? no smoking or funny noises runs good off the bottom end untill you punch the throttle then it just cuts out?

[DnB_racing]

did this just happen after converting to kick? I mean first time after, or was it a while after, and was the battery removed or is this a combination kick/electric

was all the work you've done because of problem or was any done first, also have you ever unplugged any harness connectors? if so are you absolutely sure you didn't loose the rubber ring inside the connector to keep moisture out?

I would look real close at all your connectors, any that appear yellow or dark have experienced some heat, the darker the look the worse the heat has been,
heat is caused by high resistance, high resistance in any connections will cause your quad to stumble

give a GOOD explanation of chain of events of the what happened and whens and we can work this out

[quad2xtreme]

when I first read this, I wondered if it runs fine if you moderately increase the throttle and does it make it to top end speeds? Or does it only cut out if you totally stab the throttle?

[Houser450]

dnb- i actually bought the quad with the problem, and the one way bearing was also bad in the starter system so i did away with all of the electric start including battery. i have had connectors apart and they seem fine i used dielectric grease when putting back together. i am now in the process of cutting the harness to make it a race cut harness using one of your diagrams. all the stuff that i listed changing out i changed out trying to fix the problem and nothing seemed to help tomorrow i should have the harness back in and see if for some reason that helps

quad2extreme- it is the most noticeable when you really stab the throttle, i think it still does it if you roll on the throttle though i might have to test it some more to say for sure

[quad2xtreme]

Originally posted by Houser450
dnb- i actually bought the quad with the problem, and the one way bearing was also bad in the starter system so i did away with all of the electric start including battery. i have had connectors apart and they seem fine i used dielectric grease when putting back together. i am now in the process of cutting the harness to make it a race cut harness using one of your diagrams. all the stuff that i listed changing out i changed out trying to fix the problem and nothing seemed to help tomorrow i should have the harness back in and see if for some reason that helps

quad2extreme- it is the most noticeable when you really stab the throttle, i think it still does it if you roll on the throttle though i might have to test it some more to say for sure

The reason I asked is the HRC setup also does some mods to the carb. I found these to be key that folks who just try to rejet miss. If you take the airbox lid off, change the exhaust, and cam...it can be a bit more complicated than just jets. It is changing jets, the needle, and the accelerator pump setting. If you can slowly get it to roll on and run at max speed, I think you are starving for fuel when you just stab it.

[Houser450]

I took the carb off of my houser crf and it still had the same symptoms, that's kind if why I am looking elsewhere right now. Also right now I have stock cam,filter, and exhaust. A couple other things ive checked are flywheel key and pressure relief valve in the left case cover. Do crank seals go bad, and if they do what symptoms would I have?

[DnB_racing]

Just a quick note on dielectric greese make sure that it doesn't get into the connections as its non conductive

[suspension101]

what gearing are you running?

[Houser450]

Stock gearing

[suspension101]

Ok, I've had some 04-05 before that the gearing was low enough that it started hitting the rev limiter way too fast. Did you check for metal shavings on the flywheel?

[Houser450]

There were no metal shaving on the flywheel or in the oil that I drained

[suspension101]

Have you swapped the flywheel out? I've seen a bad flywheel on a 400ex 3 times with very close symptoms you are describing on your 450. It would start right up, idle perfect but when you stabbed the throttle it would cut out like you were hitting the rev limiter.

[Houser450]

I haven't but I guess I don't see how the flywheel can be bad I have changed the pickup coil and stator though

[quad2xtreme]

You've probably checked the timing a dozen times already. If you haven't, make 100% sure you aren't off by one tooth.

You are at the point I've nearly needing to drop your engine into another quad that is running perfect to eliminate any wiring/electrical issues. You'd at least know it is in your engine/carb if it still runs the same. If not, you'd know it is in your electronics.

[CJM]

Id be taking a look at the stator again.

[suspension101]

Originally posted by Houser450
I haven't but I guess I don't see how the flywheel can be bad I have changed the pickup coil and stator though


The flywheel is what helps create the power to your cdi! When you run a magnet around a coil of wire it creates AC electricity. The electrical systems on these bikes are very sensitive so if there is a problem with the magnets it will cause a problem while running the engine.

[Houser450]

Originally posted by suspension101
The flywheel is what helps create the power to your cdi! When you run a magnet around a coil of wire it creates AC electricity. The electrical systems on these bikes are very sensitive so if there is a problem with the magnets it will cause a problem while running the engine.


I guess since that's about the only part of the electrical I haven't switched its worth a shot
I'll see how it works with the harness cut, and if no change ill try flywheel

[DnB_racing]

Originally posted by Houser450
Do crank seals go bad, and if they do what symptoms would I have? if the crank seal on your clutch side is bad you will see a mix of your oils, usually your crank oil will get cloudy because of the mix with gear oil,

most time you wont even feel a big difference in performance, but the oil will look different,

or sometimes overfull on one side and empty on the other, but then you will feel something either slipping clutch or lack of power

first symptom is usually the cloudy oil

[Houser450]

I think I'm on to something. since I exhausted all of my electrical problem ideas, I decided to go back in the carb I plugged the leak jet totally. The wheeler ran without any bogs or hesitations. I just don't understand why. it had the stock leak jet in it. Is there a way to set the acc pump to stock settings?

[Houser450]

well i cant seem to get the wheeler to run right with the leak jet in it. i know a lot of people run smaller leaks, but it should still run pretty decent with the stock one. i was wondering when you guys mess with your acc pumps do they shoot straight into the cylinder head? mine kinda shoots right to the bottom of the intake almost hits the boot if i remember right. also i checked the diaphragm and it all looks good. I also messed with the timing of the pump didnt help.

[DnB_racing]

just keep the leak jet plugged, you wont be the first to complete plug it,

I've seen the ap squirt across the room so if your isn't shooting fuel 10 feet you might have something wrong,
also don't mess with the screw that has the spring that's not a ap timing adjustment

goggle accelerator pump mod and you should find a few good demonstrations better then I could explain

[Houser450]

UPDATE UPDATE UPDATE

i still am working on figuring this thing out. it is definately something in the carb now i took the carb off of my buddys 07 and it ran mint. I dont want to just plug the leak jet, because i dont feel this is fixing the problem. I put a new diaghram kit in, a new needle in it and i put a 55 leak jet in it still bogs out horribly. i split the carb body and nothing jumps out at me. I didnt wreck the orings in there but i would still like to replace them, maybe somebody soaked the carb in something and wrecked these gaskets (o rings). Does anybody know where to get these it sounds like they are had to find?

[DnB_racing]

im not sure I understand what your saying??? does plugging the leak jet get rid of the bog?

[Houser450]

Yah it will get rid of the bog with the leak jet plugged, but I'm thinking the carb is loosing pressure between the diaphragm and the nozzle. Also I know it's not suppose to make it harder to start with it plugged, but it sure seems like it does.

[gncc571]

Yah it will get rid of the bog with the leak jet plugged, but I'm thinking the carb is loosing pressure between the diaphragm and the nozzle. Also I know it's not suppose to make it harder to start with it plugged, but it sure seems like it does.

Did you ever figure out your problem? I've been working on one for a buddy and it's doing the same thing.

[Houser450]

Did you ever figure out your problem? I've been working on one for a buddy and it's doing the same thing.

It ended up being something in the carb but I never found out what was actually causing the problem. I ended up buying a used carb and it fixed the problem. I tried everything jets needles leak jet accelerator pump.ieven split the carb whereyournot really suppose to split it and I couldn't find any thing out of the ordinary.if you can find a carb off a buddy's machine I would try it to either rule the carb out or know for sure that it is the problem

[suspension101]

I had one the other day that was doing a similar problem. Took me about 15 minutes to figure it out. There's a valve between the accelerator pump and where the fuel squirts out of the nozzle. You have to split the carburetor to access it, but this valve was sticking and not letting enough fuel into the accelerator pump. Ended up having a small piece of something in the valve. Cleaned it out and worked great after that.

[gncc571]

great thanks I'll take the carb apart and check it

[gncc571]

I had one the other day that was doing a similar problem. Took me about 15 minutes to figure it out. There's a valve between the accelerator pump and where the fuel squirts out of the nozzle. You have to split the carburetor to access it, but this valve was sticking and not letting enough fuel into the accelerator pump. Ended up having a small piece of something in the valve. Cleaned it out and worked great after that.
Where is this valve your talking about? I've got it tore apart and trying to figure it out. When you say "split the carb" do you mean taking the bowl off and then the next part that comes off that's above where the bowl bolts on? Thanks

[suspension101]

Where is this valve your talking about? I've got it tore apart and trying to figure it out. When you say "split the carb" do you mean taking the bowl off and then the next part that comes off that's above where the bowl bolts on? Thanks

Yes remove bowl and next piece above that. It's a brass piece

[400cc]

are you talking about the jets? thats the only brass pieces i've seen in a 450r carb unless i'm blind

[suspension101]

You don't have to remove the bowl to access this valve. But you have to remove the 4 screws that hold the 2 halves of the carburetor together. Once you have the carb split you should see it.