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Big Bore Problems Gonna burn the bike down.

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Hello,I need help. I am at my witts end. I just installed a cylinder werks big bore kit. I've done a million two strokes but this is my first 4 banger rebuild. I followed the manual and everything should be back together properly after three trys. I started it up last night and it ran for maybe 15 secs and it ran like a two stroke that was flooded then it died. I took the valve cover off and everything looks fine. My thought was the jetting. Its the stock mikuni with a 160 main 3rd clip and spacer below the clip needle and 3 1/2 turn out pilot screw. I live at sea level. The bike has a full exhaust and 3X3 done to it. And it still cranks freely so I am pretty sure the rest of the engine is ok. Please help i am about to burn the thing to the ground.

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Hello,I need help. I am at my witts end. I just installed a cylinder werks big bore kit. I've done a million two strokes but this is my first 4 banger rebuild. I followed the manual and everything should be back together properly after three trys. I started it up last night and it ran for maybe 15 secs and it ran like a two stroke that was flooded then it died. I took the valve cover off and everything looks fine. My thought was the jetting. Its the stock mikuni with a 160 main 3rd clip and spacer below the clip needle and 3 1/2 turn out pilot screw. I live at sea level. The bike has a full exhaust and 3X3 done to it. And it still cranks freely so I am pretty sure the rest of the engine is ok. Please help i am about to burn the thing to the ground.

Could be a lot of issues ,but don't think they relate to your carb (Assuming it was working before fitting the new cylinder).

Could be cam timing ,one of the piston rings broken and so on.

Would have started with the timing of the cams ,making 100% that it's on tcd (Not bdc).

You should also check if it gets fuel trough the carb. If this is ok ,time to pull the cylinder off

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Hello,I need help. I am at my witts end. I just installed a cylinder werks big bore kit. I've done a million two strokes but this is my first 4 banger rebuild. I followed the manual and everything should be back together properly after three trys. I started it up last night and it ran for maybe 15 secs and it ran like a two stroke that was flooded then it died. I took the valve cover off and everything looks fine. My thought was the jetting. Its the stock mikuni with a 160 main 3rd clip and spacer below the clip needle and 3 1/2 turn out pilot screw. I live at sea level. The bike has a full exhaust and 3X3 done to it. And it still cranks freely so I am pretty sure the rest of the engine is ok. Please help i am about to burn the thing to the ground.

May pay to check the cam timing. If it run before the BB it should run now even if the jetting is off slightly.

If you are going to burn it I will swap some fire wood for your bike.:banghead: :banghead: :foul::)

Sorry other than that I can't help you.

Glen.

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I checked the cams this morning and didn't dawn on me untill you said something. The arrow and the exhaust cam that is supposed to be parralel to the head was a bit off of parralel. Could that casue my problem and could that have messed my engine up?

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wow....good to know.

Yes, you can never be too careful about timing cams! :banghead::)

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I've got some stock OEM , non bent valves with 2200 miles on them if you need em.

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Thanks for the info, guess I'll be more careful next time. I 'am going to take the head off tonight and see what damage my dumba$$ did. As for the valves thanks for the offer.

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a check of the valve clearnce iwll indicate bent valve.

if it has "alot" of clearance you know the answer.

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I checked them and looks like just one of the exhaust valves are bent and the retainer clip is in pieces. The piston doesnt look like it even got touched. I think I got off pretty lucky.

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