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Big bore - ut oh!

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After having the bike down for two months I finally have my first Saturday off and am able to put the bike back together (with a little help from members of this board). I have the MT440 resleeve, RHC cams and valves and am running 13.5:1 with 94 octane. Started the bike up and it ran for a minute or so then cut out. Started it up and ran for a few seconds. Tried the third time and the starter motor is turning, but it is not catching on anything to get the "thump, thump" of the piston trying to fire, just the whine of the starter going round and round. What should be my first place to look to sort out this problem? Thanks for the help guys!

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You have seriously screwed up your bike. It's probably only worth about $500, so you ship it on down to me and I'll give you what the bike is worth.

Just kidding with ya man. If the bendix isn't engaging the crank, I really don't know what the problem could be. Ed is gonna be the man for theis one.

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$500 you say? How about $525 - that sounds fair to get the headache off my mind :ride: For what it is worth the jet blast out of the tail pipe was much stronger than before with just the FCR and pipe :thumbsup:

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are you sure you put the piston in the correct direction?big valve cut outs on the intake side?

maybe you just fouled a plug.

did it sound noisey?

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No noise, no fuss, just stopped. I installed the piston correctly (with the laser etched arrow pointing out the exhaust) and think I did everything correctly. Would fouling the plug make the piston not move and cause the "thump, thump" sound of the engine turning?

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Make sure fuel drains from the float bowl using the drain screw. If OK, check to make sure that the fuel valve is working on the tank by using a vacuum device. And also make sure that the vacuum hose to the tank valve is connected to the carb neck and to the back of the tank valve.

Try taking the air filter off and squirt some fuel in...any changes? Did you take the spark plug out and check for a spark. You could put a coupla drops of gas in the cylinder when you have the plug out. Might help on the restart.

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if its just a starter issue you could try pushing starting it.?.?.?, ... after checking the before mentioned ideas.

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I had a exhaust valve shim get cocked under the lifter after approx 1 min

running time (after base gasket install) and it lost all compression.

It was holding the valve open. May want to recheck the clearance.

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no sound good matttys....

almost sounds like your starter gear or something is loose...

If you want another non-technical dumb ass to come listen, I can stop by

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Can you turn the motor over manually with the crank bolt? Let us know what the cause is once you find it. Good luck!

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Almost sounds to me like you aren't getting gas and just drained the float bowl.

Check the simple things first. Gas, Spark, Compression? Then go from there.

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After having the bike down for two months ...

Tried the third time and the starter motor is turning, but it is not catching on anything to get the "thump, thump" of the piston trying to fire, just the whine of the starter going round and round. What should be my first place to look to sort out this problem?

Is it possible you have a very weak/ almost dead battery?

Did you fully charge it after sitting for 2 months?

Bob

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Sorry for the delay - had to go out of town for a family emergency last night. Back in town and will try all the mentioned suggestions and report back.

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what else did you have apart?

The only parts that I disassembled was the top of the engine.

Spark plug looks fine. Gas OK and nipple connected to petcock. Battery OK. I think compression may be the issue. I can rotate the crank with a wrench and there is hardly any compression (if any) with the spark plug tightened down. With that said, when I try to start it sounds like the start motor is just free spinning. So it is either the compression or something in the linkage of the starter/engine.

Any suggestions on what to tear into first? I am draining the oil and checking the valves/shims next, but I think they will be OK.

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OK, installed new plug and there is some compression. I hear the whine of the starter with no "thump. . . . thump . . . . thump . . . . start," instead it sounded like the starter is whining then a single shot gun blast went off. Happened a few times without the sound of compression in between. Would an iridium vs. regular NGK plug make a difference? I have the iridium installed.

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No difference from the plug. Take the valve cover off and look at the tops of the valves to make sure all the cotters are still holding them down.

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I have a buddy with an 05sm that is a tech at the Suzuki shop in town. During his lunch break he installed my valves and clearanced everything by putting in new shims. Intake clearance was 0.2xx mm and exhaust was 0.3xx mm. Clearance is supposed to be 0.10-0.20 and 0.20-0.30 right? So that means that the valves are a little off. I think this is a good place to start trying to solve the problem, but I think there is more going on here. Everything else inside the head looks OK and as it should be.

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