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Discussion Starter · #1 ·
Ok guys here's the deal. It's been freezing cold for the past month, my 07 450er was getting harder to start so I adjusted the valves. Stator side exhaust was in spec and the clutch side was barely tight, so I shimmed it. (still in spec but thought why not while I'm in here) Both intakes were at 0.004 so I shimmed them to .006. I followed Ghott's instructions, I work on atvs and bikes for a living but this is my first 450r. My decompressor is at 55psi (I believe), my compression gauge isn't very accurate. I rented a broke one, that didn't help. Either way it won't start. It will backfire every so often, and even started once. I warmed it up and killed it. Then it wouldn't start. The next day I tried warming the motor with a blanket over the bike and a heater underneath. Won't start. Starter is turning it over just as fast as before so I think the starter clutch is ok. All my timing marks are dead on, got good blue spark too. Been at it for 2 weeks, pulling my hair out. Read almost every thread on this and am getting nowhere. Can't pull start it either cause of the snow. Mods are: K&N filter, HRC kit, DG slip-on, Pro-Armor kill tether. Ran great before I shimmed it. Jetting is spot on, by what the plug reads. Im at sea level, 42 pilot 168 main 3rd clip on the needle, 2 1/2 turns out and plugged leak jet. Ac pump is squirting. What could it be!???
 

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It was getting harder to start, may be not from the vlaves clearances. You can perform a leak down test if you have a compressor, maybe something is wrong with rings, that odd ex valve, you will hear where the air escapes. 0,004 is still ok.
I never touch the ex valves, they won't move at all, if they do they should follow each other.
Try adjusting the decomp per the manual, exhaust clearance + 0,010, maybe you got that wrong.
 

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id try what gboezio said, the 07 adjuster needs adjusted to a total of .021, so the .011 for exhaust clearance, then .010 for the adjuster arm. if it don't start then, you prolly gotta tear the carb off and your jets are dirty.

the ethonal in the fuel reacts with the brass jets and created crud that clogs them easy......I drain my carb now if its gonna sit more than 2 days.
 

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Discussion Starter · #4 ·
I checked the carb and all is good, and set the decompressor like the manual said but it acted better at .025. That's where I got the 55psi. And I did a leak down test today and couldn't hear any leaks, it dropped only about 4psi after 3 hours. So I think that's fine
 

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60psi with a comp tester is spec so your pretty dang close.
 

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Fairly fast foreigner!
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Timing..
 

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Discussion Starter · #7 ·
Timing marks line up on crank flywheel and cam, been over it, 20 times now lol don't see why I would start and run fine, then I get it all back together and then it won't. When it started I pumped it twice, pulled the choke and it fired instantly. So I figured all was good and bolted the fenders and tank back on, then no start lol
 

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Sorry on phone in work earlier.. didn't read all of orig post.. like others said.. decomp - You can get a compression gauge for $20 - $30. When I had e-start.. about 65psi worked best.. but it would start ok @ 55psi though.. I'd get a gauge again and re-try it.. two weeks is long enough...
 

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The fact that you need to go to 0,025 to get in the ballpark, you may loose some pressure, a leakdown test...and then some money !!

Maybe just bring it to TDC and put air pressure in the cyl, you will hear it.
 

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Discussion Starter · #10 ·
The fact that you need to go to 0,025 to get in the ballpark, you may loose some pressure, a leakdown test...and then some money !!

Maybe just bring it to TDC and put air pressure in the cyl, you will hear it.
Well my gauge isn't very accurate, but I did put it at tdc when I pressurized the cylinder, didn't hear any leakage. This thing has ran great. Then we got a good freeze and snow, had trouble starting, I'm sure because of the weather so I figured I'd check the valves. Was surprised they had never been adjusted and weren't hardly out of spec. It started fine in 50+ degree weather. I mean hit the button and it would Instantly it was running. Should've left it alone I guess lol
 

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Discussion Starter · #11 ·
Sorry on phone in work earlier.. didn't read all of orig post.. like others said.. decomp - You can get a compression gauge for $20 - $30. When I had e-start.. about 65psi worked best.. but it would start ok @ 55psi though.. I'd get a gauge again and re-try it.. two weeks is long enough...
Definitely gonna get a compression tester, and see where it's at on a new gauge. Hopefully I can pull start it tomorrow and get it started. I read one guys post with the same problem, he pull started it and after that all was good. She'd fire up everytime afterwards. Hopefully that'll work out for me lol
 

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Discussion Starter · #12 ·
Anything electrical that could cause this? Was thinking maybe trying to get the under tank heat shield in I may have pulled a wire or something but can't find any issues. And since I have spark I think my throttle switch and carb switch are good
 

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Fairly fast foreigner!
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Anything electrical that could cause this? Was thinking maybe trying to get the under tank heat shield in I may have pulled a wire or something but can't find any issues. And since I have spark I think my throttle switch and carb switch are good
Correct.. If your getting a good spark your carb / throttle switch isn't issue.. If decomp doesn't solve issue and you are 100% on your timing marks on cam gear / timing gear.. Maybe worth checking the flywheel / key to see if it's gone " out of time" there..
 

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Discussion Starter · #14 ·
Correct.. If your getting a good spark your carb / throttle switch isn't issue.. If decomp doesn't solve issue and you are 100% on your timing marks on cam gear / timing gear.. Maybe worth checking the flywheel / key to see if it's gone " out of time" there..
Would the key be sheared if my T mark lines up with the other timing marks?
 

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Would the key be sheared if my T mark lines up with the other timing marks?
Just worth checking if everything else is good. Right..? There's only so many things that can prevent it from starting.. Spark timing is one of them .. Rule everything out one at a time..
 

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Discussion Starter · #16 ·
Just worth checking if everything else is good. Right..? There's only so many things that can prevent it from starting.. Spark timing is one of them .. Rule everything out one at a time..
Yeah I know it's just hard to wrap my head around it since the marks still line up. But it's worth a shot, wouldn't be surprised by anything at the moment lol anybody know how to check the timing with a light and not get coated in oil? Lol thanks for all the help! GREATLY APPRECIATED!
 

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Discussion Starter · #17 ·
Okay I checked the timing again and with the crank dot lined up, the T on the flywheel is ahead of its mark by an 1/8th of an inch. Cam lines up perfectly. So maybe the key is sheared? I'm waiting on a flywheel puller and holder so I can't really tell for sure. Would that sound right for a bad key? And with it being ahead of the mark the timing would be advanced and harder to start, any way to retard the timing so I can hear it run again for piece of mind? I read something about the tps being bypassed and changing timing, would that retard or advance it?
 

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Discussion Starter · #18 ·
Pull started it and fired right up! Runs great! Starts right up now! Thanks for all the help guys! Much appreciated!
 
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2006 trx 450er. Stock motor, sparks full exhaust, elka legacy series shocks, and many more boltons!!
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What was the oroblem im gojng through that right now.
Get bud that post was years old, I’ve made the same mistake, sometimes the little date isn’t noticed right away. But did you get the issue figured out yet? If not what’s the problem? Not starting? Does it turn over? You can get good advice on this site. (Once in a while not so much)
 
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