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450r XC Rider
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Im working on an 08er and I adjusted the valves and they are perfectly in spec. but the thing will just not start. It has a hrc cam and i set the intakes to .006 and exhaust to .011. The intakes were very tight and the exhaust were dead on. I know it is something to do with the decomp. but I cant figure out what it is. I put a couple of pics up to show what it looks like all put together. Hopefully somebody will be able to pinpoint it if there is a problem with it. I put a new spark plug in it and have taken the cam tower off and cleaned the inside of the cam out twice. If appears to be moving properly when you pull the spring with your hand and the pin inside the cam moves, but it may not be closing or opening all the way. Im stumped right now and hopefully somebody can help me out. Oh and it will roll start and run like a champ. Its in time perfectly too.
 

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There was an 08ER recall concerning this. Have you looked into that? Maybe ask a dealer about the recall?
 

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I think you may have the decomp cam and pin turned the wrong way. If you look at the pin it has a groove cut on one side that the decomp cam engages to move the pin up and down. It's hard to tell from your pics but it looks like the decomp weight is extended in the pic, when the bike is off the weight should be retracted toward the center line of the cam and the pin should be extented. If I am seeing correctly you might need to rotate the decomp pin and decomp cam 180deg.
I'm trying to think if you can even install the gear with the pin in backwards but I can't remember, either way this will either fix it or get you started on fixing it.

Or as Skip said pull the Decomp cam out and make sure the little pin that engages the decomp pin hasn't broken off.

Hope it helps.
 

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450r XC Rider
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Discussion Starter #4
thanks for the answers guys. its got the hrc cam so i think the recall would only be on the stock cam. not 100% sure though. and we took the cam out and inspected the pin and found nothing. i bet we have literally took it apart 20 times and it just wont work right. when you pull on the spring-loaded gear that pulls the cam pin, the pin in the cam moves back and forth. i just dont know if its moving far enough to open the valves to the right spec. we have flipped the cam and shaft inside the cam around several times and still nothing.
 

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Is the top of the pin worn down, maybe? I have no earthly idea what the spec is on the pin maybe someone has one laying around that they can measure or the service manual might say. Or look at the pin and see if it shows any signs of wear. Check the compression with a gauge to see just what it is.

I'm just throwing stuff out now.
 

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450r XC Rider
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Discussion Starter #7
ive tried all of that srt...except the compression gauge. and i dont have a manual and cant download one because my computer crashed and my work computer sucks ass. im gettin ready to just take it to the shop. i dont know about this auto decomp stuff. i tried to talk him into getting an 07 cam setup lol. 450tr yes it cranks over and over and it almost wants to start but its just not there. i just think the pin is not goin back closed all the way or is not opening all the way and isnt moving the valves far enough but ive tried everything i know to do
 

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my 2008 450er would not crank a full turn.. kinda like a dead battery... I put a new batt and changed my starter since I fried the other one and still barely cranks..

Called Honda Canada and they will repair free of charge.. waiting on them to get the parts..

Type your VIN here

http://motorcycle.honda.ca/safety/recalls%5Cjh2te32258k200233


What is the problem? During high-load operation at extremely low rpm, the crankshaft may experience instantaneous reverse rotation which momentarily actuates the engine decompressor system. When this happens there is excessive force on the decompressor actuation pin, causing it to bend or break. If the decompressor actuation pin is damaged the engine will not start.
 

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Im having the same problem..i got the new pin and small shaft that goes as a kit.. This is the second day im strugling to put it together... Is there someone with a video that can help me please.. Thanks
 

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I think you may have the decomp cam and pin turned the wrong way. If you look at the pin it has a groove cut on one side that the decomp cam engages to move the pin up and down. It's hard to tell from your pics but it looks like the decomp weight is extended in the pic, when the bike is off the weight should be retracted toward the center line of the cam and the pin should be extented. If I am seeing correctly you might need to rotate the decomp pin and decomp cam 180deg.
I'm trying to think if you can even install the gear with the pin in backwards but I can't remember, either way this will either fix it or get you started on fixing it.

Or as Skip said pull the Decomp cam out and make sure the little pin that engages the decomp pin hasn't broken off.

Hope it helps.
Hey bud are you still on here lol
 
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