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Discussion Starter #1
Hi everyone,

I have a KLF400, I'm having difficulty starting the motor.

First of all the starter motor wasn't cranking the engine, so I replaced the starter clutch gear bearing and race.

Now the motor will crank but it appears to be really struggling when the spark plug is torqued in the engine.

Its like when the engine is under compression the starter motor will eventually crank the engine but it seems to struggle a lot. Even with a new battery I get the same results!

any ideas?
 

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Welcome to the forum. I wonder if your timing chain has jumped a tooth. That can cause it to be had to turn over.
 

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Discussion Starter #3 (Edited)
Thanks Rdc,

I will be whipping the rocker cover off and checking timing, just want to do a compression check and check the valve clearances first.

I just find it odd how it’s cranks perfectly without spark plug, it makes me think the starter motor has lost its torque or something?

also when rotating the crack by hand on one of the strokes I hear a strange clicking noise coming from the head/cylinder
 

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Discussion Starter #4
And also, every now and again when trying to start the motor I will get a backfire through the carb
 

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Discussion Starter #5
compression bang on - reading 60psi on a cold engine so can expect that to creep up as engine is at operating temp. Checked the valve clearance to find that all 4 valves where over top tolerance by 0.2mm so adjusted them back to spec(from workshop manual)

now the ATV cranks fine not struggling what so ever, but now I’m experiencing major back fires through the carb Intake also Spitting fuel out too.

am I missing something here? Maybe my cam timing is out? Anything else I should try?
Cheers!
 

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That’s what I’m thinking. Either the cam jumped a tooth on the chain or the tensioner has a problem.
 

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Discussion Starter #7
That’s what I’m thinking. Either the cam jumped a tooth on the chain or the tensioner has a problem.
Thanks for getting back mate, I think it’s time to check the timing components, any telltale signs I should look out for?
 

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Pretty simple. Find your timing mark on the flywheel and make sure it’s TDC. Search online where the cam mark is supposed to be.
 

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Discussion Starter #9 (Edited)
Pretty simple. Find your timing mark on the flywheel and make sure it’s TDC. Search online where the cam mark is supposed to be.
So I checked the timing and it appeared to have jumped a tooth, I put it back to where it should be and it fired up straight away, then it started making a disturbing rattle so I shut the bike off.

I have a feeling that the cam chain has stretched and it loose, even with the tensioner on its maximum tension the chain sounded like it was still rattling around, also I found that two of the valve stem seals had lifted off the seat up the valve Stem.

so will be replacing the cam chain Head gasket and stem seals on all valves. And fingers crossed this will sort the issue out!!

I also forgot to mention that The ATV had a front end collision which caused the engine to suddenly come to a stop. And I’m almost certain that this has caused the chain to jump, in the process of that jump I think it’s damaged/stretched the chain.
Let me know your thoughts?
 

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You might want to check your cam chain guide. I think they are made out of plastic. Could be broken.
 

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Discussion Starter #11
Cam chain guide and tensioner seem to be ok, don’t look worn or broken, the chain was stretched
3513

Not by much though but hoping enough to be the cause of the problems I’ve experienced.

also the sprocket on the crank looks worn but no teeth are missing, I’mnow hoping I don’t need a new crank
 

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Discussion Starter #12
So it’s all back together, now I’m only reading 30PSI on compression test and still won’t start, bike still seems to be difficult to crank. Running out of options here. Don’t understand why it was reading 60 and now it’s reading 30 starting to loose the will with it
 

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Discussion Starter #13
I’m getting the same problem as first, engine is struggling to crank past the compression stroke. Cranks perfect without spark plug.

could the starter motor be the issue? If I can’t fix this soon it’s going to be sold as spares or repairs
 

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It looks like the last thing you could do is throw a starter at it but I would try to find one on eBay cheap.
 

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Discussion Starter #17
Thanks for reply again,

I will have a look and see what I can find!
I’m also noticing that the starter motor is getting very hot, and also battery is draining incredibly fast.

also when cranking the voltage drops below 8 volts.

not sure if this info means any thing
 

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Could mean that you have a bad ground. You might want to check where the battery grounds to the frame. Clean it up and see if that helps.
 
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