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  #1  
Old 26-04-2008
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Goutman Goutman is offline
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Trouble starting wr 426

Howdy guys and girls.... recently purchased a 02 wr 426. Upon first inspection the bike fired first kick on a cold motor, since getting it home i have struggled to make it start. I have changed spark plug, its getting spark, its getting fuel through to the carby and has a heap of compression. I dont use the throttle to help start it as they have a mechanical fuel pump, and use the decomp lever. The method in which i use to start it goes like this... fuels on, chokes out, kick down till i get some resistance, engage decomp lever, kick down a further poofteenth, release lever and give it a boot. It doesnt even give a hint of wanting to fire. The only thing i have done since purchasing the bike is add a tank of premium fuel and a new plug.... what are your thoughts?
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Old 26-04-2008
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you are definately doing it correctly. I used to have a 426, and it takes some time to get the starting process down pat.
I would remove plug and check for spark (maybe you have a dicky kill switch/lead or a faulty plug)
next option is to push it down a big hill, hold decomp in, click it into gear and let engine get up to speed, then release decomp. If it doesnt start then, its not going to start
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Old 26-04-2008
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ps. It is possible to fuel foul a new plug in a 4T, I have done it myself.
If it has spark, try another plug first up
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Old 26-04-2008
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Thanks for reply guys... i have drained the carby incase there was anything in there thats not meant to be. I have also tried 2 plugs i being brand new, and have kicked it over with the earthing out and is getting good spark. I have also removed the fuel line to the carby and its getting fuel. I havent removed the magneto to inspect yet but will do today.
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Old 26-04-2008
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I've got a 450 and regardless whether the choke is on, I turn the fuel tap on, give it time to fill the bowl, give about 3 full pumps with the throttle, release throttle and kick.
Worth giving it a try.
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Old 26-04-2008
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well "vertex" aka Jezza and myself checked the valve clearences today and they all measured to manufactures specs so i think this could be a shop job.
Good spark, loads of compression, mouthful of fuel is all the ingredients for an operational bike.... will try and get the bike in next week. Now to find a reputable mechanicany suggestions eastern burbs of melb
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Old 26-04-2008
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disconnect the kill switch first in case its shorting out. i'd tow the *@#&*@#&*@#&*@#&er with a car if you dont have a hill close by , dosnt have to be fast , just to see if you can get it to fire up.
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Old 26-04-2008
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surely there is a DBWer in the area that could lend this bloke a hand?
its got compression, spark and fuel, it should go.
Only time I have been in a similar situation (was a WR200) when we had spark fuel and compression and it wouldnt start was when the flywheel key has sheared off and the timing was out to the buggery
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Old 27-04-2008
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Quote:
Originally Posted by Goutman View Post
Howdy guys and girls.... recently purchased a 02 wr 426. Upon first inspection the bike fired first kick on a cold motor, since getting it home i have struggled to make it start. I have changed spark plug, its getting spark, its getting fuel through to the carby and has a heap of compression. I dont use the throttle to help start it as they have a mechanical fuel pump, and use the decomp lever. The method in which i use to start it goes like this... fuels on, chokes out, kick down till i get some resistance, engage decomp lever, kick down a further poofteenth, release lever and give it a boot. It doesnt even give a hint of wanting to fire. The only thing i have done since purchasing the bike is add a tank of premium fuel and a new plug.... what are your thoughts?
Talk to the previous owner and find out what he did to start it..

Seems odd that when you get it home it won't start with spark, fuel etc etc.

Give him a buzz, coz it will be cheaper than a local shop..
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Old 27-04-2008
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Quote:
Originally Posted by hamish View Post
surely there is a DBWer in the area that could lend this bloke a hand?
its got compression, spark and fuel, it should go.
Only time I have been in a similar situation (was a WR200) when we had spark fuel and compression and it wouldnt start was when the flywheel key has sheared off and the timing was out to the buggery
You've probably hit the nail on the head there! Common problem I understand on the earlier models.

Probably easy enough to check by making sure the piston is at TDC (kebab stick thru the sparkplug hole) and check marks on rotor line up.

Goutman, when you say good spark, I take it you mean a nice fat blue one? Is the plug ever wet when you take it out to check it?
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