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Bike won't start or run

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So I picked up an 06 450x. Seemed like it was in great shape. Jetting felt 'off' - previous owner mentioned it had a Dynojet kit, which I heard was crap. I took the bike apart today, removed the carb and put in a 165 main, NCVS needle on the 3rd clip, a 45 pilot and 55 leak jet, as I'm at about 1300 feet, temps usually 60-90 degrees. Took the starter jet (70, stock) out and made sure it was clean. Installed a Tokyo Mods AP spring. Made sure it was pretty clean, put it back in the bike, checked the valve clearance (right intake was a tiny bit tight but in spec), installed a new plug (the NGK iridium recommended) and generally cleaned up the bike. The carb has an aftermarket air screw; I set it to 1.5 turns out to start. Put new throttle cables in, as one had a nick exposing the cable. Idle speed adjuster just touching the throttle rod. Cleaned the Twinair filter, sprayed it good with Maxima Fab1 oil, let it dry/tack up for a few hours. The backfire screen is still in, but I took the snorkel off and cut the top a bit, baffle from the OEM exhaust removed. 

 

I can't get the bike to start. I spent about 2 hours kicking it and using the e-start. The battery sounds like it's almost drained now. I managed to get it to start twice, but it wouldn't idle and would just stall before I could adjust the idle. It didn't seem to be running right either. Kicking it now does nothing - it doesn't even seem to want to start. I made sure the aftermarket air screw went back in right, with the little o-ring. I've tried giving it a couple whacks of the throttle, tried starting at full throttle, tried the choke on and off, tried kicking out any excess fuel with the hot start open in case it was flooded. Tried running it on reserve in case I put the fuel lines on backwards...haha. Fresh gas and everything. What the hell did/could I have done wrong? I absolutely don't want to take the carb off the bike again - that was a huge pain in the ass. I timed the AP squirt as well, after changing the spring, and it was fine (not that it should be affecting it at this point). The two vent hoses from the carb/engine aren't blocked. It's a Canadian bike, so doesn't have any of the smog stuff. I put the hot start thing back in properly. 

 

Any ideas?

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Pull off the tank and look for the coil ground wire....which probably came loose

 

 

I'll take a look...but wouldn't it not start at all if that were the case?

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On a side note, I would refrain from kicking it, there is a very good chance you'll crack the side case. For whatever reason Honda dropped the ball on the design and its really prone to cracking.

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right

 

Well, it's flodded now, so open the throttle, press the kill button, and kick it through a dozen times.

 

Then start from scratch: choke on, pump the throttle three times, throttle held shut, kick motor over

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Just checked all the wiring - connections are all good and secure. Let the bike sit for an hour and tried again...still nothing. When kicking it, it sounds like there's no combustion whatsoever. All the jets I put in the carb were new, Keihin jets (aside from the starter jet, which was stock). I'll check the valves again, make sure I got good measurements (although I was certain I was at TDC last time). 

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Before going any further, confirm the following.

 

Compression, followed by leak down test (should be north of 120psi, leak down should be less than 25%)

Pull spark plug and confirm spark while kicking / elec start ( should be bright blue)

Clean carb THOROUGHLY. 

 

If all of those tests pass, there is no reason it should not start. If one fails, come back and tell which one failed. These things are super simple if attacked using some methodical troubleshooting.

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All good ways to trouble shoot except the compression method. The x has a auto decompression mech. Will prolly only read about 60 psi. I never checked it on the X. Leak down is the way to go.

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All good ways to trouble shoot except the compression method. The x has a auto decompression mech. Will prolly only read about 60 psi. I never checked it on the X. Leak down is the way to go.

 

Ah very valid point. I am new to these auto-magical de-compressors. I'm sure the FSM goes over all of this stuff as well with tolerance specs. I'm just going off of general mechanics 101.

 

 

I got a feeling if its fine on compression, its something simple. Either junked up carb (main culprit) or its going to be a loose / chaffed wire. Either at the coil or maybe kill switch. I've often seen both cause all sorts of buggy stuff.

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Awesome, thanks guys. I'll check compression using the 5th gear/rear tire spin method tomorrow, as well as a double-check of the valve clearances. 

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Have you actually confirmed you have spark by holding plug onto the motor and kicking it over? Could have been a dud plug you installed.

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Did you ever have the timing chain off or loose while you were checking the valves? Just 1 tooth off and these bikes will not fire.

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Any update? My guess is timing off, or the tensioner for the timing chain is too tight...

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Never had the timing chain or cam off when I checked the valve. Timing chain doesn't seem tight; nothing appears worn or otherwise out of place. I don't think anything with the wiring is messed up - there seems to be a strong spark when I checked it, and the bike turns over from the e-start ok (although the battery is pretty drained at this point - battery tender in the mail right now).

 

So I tore her apart again today. Double checked the valves; left intake perfect, right was .001 off (but in spec still), exhaust was fine. I bought another new plug to throw in; it seemed to have a stronger spark than the previous one (also new) when I checked them back to back, but still no fire when I kicked her over. Took the carb off again to check my previous work. Sprayed some contact cleaner in the jets; again, they're all new, so all were clean. Double checked the needle; clip on the third ring of an NCVS. Main at 165, pilot at 45, leak 55. Compression seems strong when kicking, but it doesn't seem to even want to be firing. I took the decomp off the carb as well to take a look and re-grease; seemed fine. Took the carb partially out again. I can see the AP squirt coming though to the front (engine) side of the carb when I whack the throttle. Double checked the airbox and header/exhaust to make sure I didn't leave a rag inside either...haha.

 

Not really sure what else it could be. Maybe the pilot jet passage way or something is clogged...? I'll try kicking it over in the morning and pull the plug to see if it's wet - I'm sure the carb itself is getting gas as the AP squirt is strong and the bowl fills up pretty quick. Other than that, I'm at a loss here.

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So I'm not sure what the hell I did today - went back out to tinker a bit this morning; ran some gas into the carb, kicked it a few times and pulled the plug to check if it was wet. I figure I didn't really kick it enough, so I threw the plug back in, kicked it twice and the bike started running (!!!). Quickly killed it, tightened up the clams on the carb and the exhaust (had taken it all apart last night), ran some more gas into the carb and kicked it again. The bike started up on the first or second kick each time. I think I screwed up the fuel (or air?) mixture screw last night and might have the wrong o-ring at the tip (it's one of those Tusk or eBay specials with multiple o-rings) as the bike will start and run fine on choke, but won't hold idle when the choke is off and just dies. Took it for a quick rip down the street and it pulls hard. Just need to sort out the fuel screw and charge the battery. No idea what I 'fixed' but I'm guessing there was some sort of blockage in the carb that cleared out last night. 

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I highly recommend the R&D Flexjet fuel screw. So easy to adjust and fit. Look them up, you won't be disappointed!

And make sure there is no other o-rings jammed up there before installing.

Edited by Razman11

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