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The TTR250 FAQ web pages -> TTR250 -> Repairs and maintenance -> Starting problems - kgoose89
Post Info TOPIC: Starting problems - kgoose89
TTRfan


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kgoose89 wrote:

Ok I'm new here sorry if I'm not in the correct area. First off, I purchased a 2000 model ttr250 for 300 dollars. Cleaned the valves, tore everything down. Everything looks fine. I put everything back together, set timing etc. I went to start it yesterday, I've got spark but not sure if the carb is pushing gasoline. Long story short, it seems as if my intake valves are way way out of spec. With shims and all the clearance is way greater than recommended. I don't even think I could get the accepted tolerance even with much larger shims. What could be the problem?

kgoose89 wrote:

Oh and I forgot to mention exhaust valves are good and within spec with shims in place. Any help would be much appreciated. Love this machine, looks great I used to own a 125 model.

Hi there

Welcome to the forum!

I have started a new thread for you as your issues seem different to those on the thread you originally posted on. I will delete the other posts to save confusion. Hope that's OK.

Brian 

 



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kgoose89


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Yes most definitely, just looking for a bit of help I'll measure the clearances again when I get off work to see how bad they are. Maybe the springs are worn? And the valve is not seated all the way. But I triple checked using some alcohol that the zeal was tight before I mounted the head

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kgoose89


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Seal*

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TTRfan


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Hi Kris

Just to go back a stage.

When you set the valve timing etc, were the clearances within specification before finishing putting it all together and trying to start it?

If so, did you then try turning the engine over by hand? I usually do this with a socket on the flywheel bolt to make sure everything turned over smoothly.

The reason I ask is that what you describe sounds horribly like the valve timing was out in some way such that the inlet valves have been bent slightly and are not now fully closing cry

It is sometimes possible to get the cams and cam chain fitted and looking OK when the chain isn't properly seated on the bottom sprocket which allows the chain to jump teeth.

I hope I am wrong. A simple compression test would show if I am wrong in my diagnosis. Take the plug out and see if there is enough compression to blow your thumb off the spark plug hole.

Brian



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kgoose89


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Ok, that's what I'm afraid of. Clearances seemed spot on then I turned it over but the battery was seemingly dead because the started just clicked and bumped a little at a time. Hope to god for my sake that I didn't bend the valves :/

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kgoose89


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I'll test compression when I arrive home, because I noticed that after all this I removed the valve cover etc and the cams were not 10 and 2 at tcc so I quickly redid everything and now the clearance is out. I'll probably be purchasing some new intake valves

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kgoose89


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Well quick question, are the valves (intake and exhaust) supposed to sit relatively at the same level in the head with retainers and springs installed? If so I know they are probably bent haha not funny for me but ignorant mistake nonetheless

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kgoose89 wrote:

Well quick question, are the valves (intake and exhaust) supposed to sit relatively at the same level in the head with retainers and springs installed? If so I know they are probably bent haha not funny for me but ignorant mistake nonetheless

 Yep - they should all look the same height in the head.



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kgoose89


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They're bent then, you have been super helpful. I suppose you don't recommend straightening them do you? Lol

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kgoose89


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And here is my blonde moment photo of the day...20140910_185007.jpg



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TTRfan


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Bad luck Kris no

One more thing is to check that the bottom of the valve guides are still OK. They can get damaged by the bending valve stems.

Brian



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kgoose89


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Piston and guides are still ok thank the lord

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