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How do you start your YZ400..

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Hi guys being new to the thumper world im still trying to get the knack of starting my 1999 YZ400, I know you need to pull in the decompressor lever until you reach top dead centre but how do i know when ive reached it...?

The way ive been doing it so far is pulling in the decompressor and slowly kicking the kickstart all the way down until it will not go anyfurther then bring it back up and let go of the decompressor lever and kick it, For the last 3 weeks its started ok but its began to get a bit more difficult to start, So i just wanted to hear someone elses views on the way im starting the bike just incase i do it any damage, Im in the middle of giving it a service replacing the oil, oil filter , Spark plug, and air filter..

Any other views would be greatly appreciated.

Cheers Andy

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Hi guys being new to the thumper world im still trying to get the knack of starting my 1999 YZ400, I know you need to pull in the decompressor lever until you reach top dead centre but how do i know when ive reached it...?

The way ive been doing it so far is pulling in the decompressor and slowly kicking the kickstart all the way down until it will not go anyfurther then bring it back up and let go of the decompressor lever and kick it, For the last 3 weeks its started ok but its began to get a bit more difficult to start, So i just wanted to hear someone elses views on the way im starting the bike just incase i do it any damage, Im in the middle of giving it a service replacing the oil, oil filter , Spark plug, and air filter..

Any other views would be greatly appreciated.

Cheers Andy

Leave the decompression lever alone at the start. Slowly push down on the kickstarted till you feel resistance from it coming up on compression. On a 426 you can stand on the kickstarter when it's coming up on compression. Let the kickstart come all the way back up. Pull in the decomp. lever and push the kickstart down about a quarter to a third of the way. Release the decomp. lever and let the kickstart come all the way back up. Then give a full kick to start it.

Sounds like a lot, if you're not familiar with the bike, but after a few hundred times it's second nature and you don't even think about it.

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Thanks for the info and the links, Thats a great help.

Ill try starting it the way you guys have said and hopefully ill have more luck becasue thats a different way to how i was trying it..

Cheers Andy

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The advice on the decompressor is right on the money. If the bike doesn't have a bar mount hot start, that's an excellent thing to add. I use a Dr. D.

I've ridden thumpers all my life, and to me the secret of starting is: don't KICK it like you would a 2 stroke, SHOVE the kickstart. You are trying to overcome the crank's inertia. The harder and longer the 'shove', the quicker the crank will spin.

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Since day 1 of owning my brand new 2001 YZ426 I have never had a problem starting it, I don' t know what the big deal is either.... Now, if it is a little chilly outside and hasn't been started in a say 3-4 days, i'll blip the throttle about halfway twice, then start that bad boy up and ride all day long.... Until you get the hang of it, you might foul a few plugs but once you've got it down it works wonders...

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Since day 1 of owning my brand new 2001 YZ426 I have never had a problem starting it, I don' t know what the big deal is either.... Now, if it is a little chilly outside and hasn't been started in a say 3-4 days, i'll blip the throttle about halfway twice, then start that bad boy up and ride all day long.... Until you get the hang of it, you might foul a few plugs but once you've got it down it works wonders...

Priming them a little with the accelerator pump when it's really cold works very well. Just don't go too heavy with the throttle. If you flood it only slightly, sometimes you can get away with pulling the hot start button to get it cleaned out, otherwise you're pulling the plug. It's the guys who have ridden two strokes there whole life that seem to have given the four strokes a bad starting rep. They are used to dumping them and then getting on an just firing them up. I think the most I've ever had to kick mine is 4 or 5 times.

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don't touch the decomp lever to start with. push the kickstart down til it hits the hard spot. pull in the decomp lever and push the kickstart passed the hard spot, but just barely, you just have to get past that spot and it only takes about an inch of movement to do it. at this point, let the kickstart come back up to the top, then shove it down nice and hard. that's it. not too complicated. if the bike has been sitting a while, it might take quite a few kicks, but it'll start.

edit - I just checked that link that was posted...yeah exactly what he said!

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I fiddled with the starting drill for a while. By far the best was the 450 cam swap mod. Easy and cheap, no more drill.

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I dont know what the big deal is I have a 99 Yz400 and its way too easy to start, hot, cold, staled, etc, its eaven esier to start than my KLX with auto decomp, and also way esier than a XR 250

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If it seems to be getting hard to start, the valves probably need to be adjusted.

My YZ is also getting hard to start. The only way I got is fired last weekend was this : go thru correct routine (what I've been doing for last 7 years since bike was new!) accept for no choke and give it 1/4 throttle. Then it starts on 2nd or 3rd kick.

Could it be the accelerator pump isn't working? Also just checked my valves, they're within tolerance (although they're at the mininum allowable tolerance . . . . could this cause hard starting?)

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My YZ is also getting hard to start. The only way I got is fired last weekend was this : go thru correct routine (what I've been doing for last 7 years since bike was new!) accept for no choke and give it 1/4 throttle. Then it starts on 2nd or 3rd kick.

Could it be the accelerator pump isn't working? Also just checked my valves, they're within tolerance (although they're at the mininum allowable tolerance . . . . could this cause hard starting?)

I couldn't tell you exactly, but I definitely don't think it would hurt to get them a little closer to spec.

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maybe its just because I commute on my bike so I start it 2-4 times per day, but its starts first kick without hot start or choke 90% of the time. Easy. The other 10% takes 2-3 kicks and once in a while I need the choke. The most Ive ever had to kick it is after crashing when it can take 10-15 to start. These bikes are easy to start if you just understand how a 4 stroke works.

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All the above advise has been good. Here is just another little twist. I have had my YZ start by just kicking it through the cycle with the decomp lever slightly pulled in. I do this after the bike has been sitting for weeks and had been relunctant to twist the throttle. I just turn on the gas and push on the kick start lever pulling in the decomp lever slightly. Basically it feels like a little 125 when kicking, and after a few times through she lights up . I release the decomp lever imediately and all is well.

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My bike was a pain to start on the first day but we adjusted the fuel screw and new spark plug and now it's so easy I don't even have to do the drill. If your having trouble try a new plug, rejet, and adjust the valves and if your still having trouble your just a sissy. I don't see why everyone needs the 450 cam so badly

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All I do is kick it through once or twice with the decomp pulled in and then leave the decomp pulled in for the very first part of the next kick then release it as I'm kicking through and it starts

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