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Big bore won't start. :(

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So, got my big bore in, carb in, pipe in, cams in, valves shimed.

I primed the carb and started her up. It was LOUD. I could hear the cam chain rattle, so I was adjusting the MCCT and then it died. Then I undid the fuel line, and plugged it back in, it started up then died again.

Starter is going, but it won't start. 👍

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Bike is wanting to turn over, I can hear it start up a tad bit, then die before it even starts.

It's looking like a fuel or carb issue?

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Well, that didn't go very well. I had to walk it home after a mile. About the half way point I was able to start it again, then it died a little bit later, then started up again....

First, it ran fine. I was going good, shifted into second, then hit a stop light and down shifted into first. Idled, got ready to go, clutched out and it died on me.

Second, the bore is getting REALLY hot. I just filled up the coolant and everything is going good.....

Third, I hear chatter from the cam chain area no matter how I adjust the MCCT. If I tighten it too much the bike dies. I hear chatter until it does.

Fourth, seems like one of the hoses from the FCR39 melted even with it routed (The one on the throttle cable side) from the bore being too hot, or the pipe.

Fifth, when it dies, it won't start up again without 5 minutes of rest.

Sixth, when it dies, the tail pipe has steamish smoke coming out of it. Not sure since it's cold out and that's just hot gas.. but 👍

Anyone know where to get replacement hoses for the FCR carb? I like the clear pink. :ride:

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Second, the bore is getting REALLY hot. I just filled up the coolant and everything is going good.....

Sixth, when it dies, the tail pipe has steamish smoke coming out of it

Hot engine, Steam out exhaust, having to fill up coolant leads one to think coolant leak into the combustion chamber.

“steam” smell sweet? Did you TQ head bolts to 43 ftlb? Did you reuse the head gasket after it had been torque’d down previously?

Third, I hear chatter from the cam chain area no matter how I adjust the MCCT. If I tighten it too much the bike dies. I hear chatter until it does.

A: It’s loose, b: the cam chain guide mount you fixed is not holding the guide as well as you thought, c: your hearing a normal noise but attributing it to something else…. D: If your tightening the MCCT to the point you can kill the motor, that’s WAAAAAy over tightening it.

Fourth, seems like one of the hoses from the FCR39 melted even with it routed (The one on the throttle cable side) from the bore being too hot, or the pipe.

The engine case, cylinder, head should never get hot enough to melt a carb vent line… ever.

Pipe yes.

If the engine component did that, there are bigger issues then a melted line.

Fifth, when it dies, it won't start up again without 5 minutes of rest.

Engine over heated? Heat soak, fuel boiling I carb? Piston partially seizing in bore?

Check cam timing.

Check coolant level, if low, and not attributed to overflow or a hose leak.. and you are seeing vapor out the exhaust,, you have a head gasket leak.

Re install the ACCT for now, solve other issues first, then come back to the CCT.

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just to keep the thread bumped, you did turn the engine and insure cam timing is correct? where did you hear that cam chain tension is adjusted with the engine running?

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Hot engine, Steam out exhaust, having to fill up coolant leads one to think coolant leak into the combustion chamber.

“steam” smell sweet? Did you TQ head bolts to 43 ftlb? Did you reuse the head gasket after it had been torque’d down previously?

I drained the coolant when I did the big bore. So no coolant leaks that I can see. It seems the same. Head gasket has been used once, copper coated torqued to 34 or so at first, then 43ft like suggested.

A: It’s loose, b: the cam chain guide mount you fixed is not holding the guide as well as you thought, c: your hearing a normal noise but attributing it to something else…. D: If your tightening the MCCT to the point you can kill the motor, that’s WAAAAAy over tightening it.

There is LOUD chatter, then I tighten the MCCT and it goes away, but I can still hear some. The engine is LOUD

The engine case, cylinder, head should never get hot enough to melt a carb vent line… ever.

Pipe yes.

If the engine component did that, there are bigger issues then a melted line.

Perhaps it was the pipe. The bore is pretty hot, but the pipe is hotter. The hoses did move around and one of the lines was burnt, so I assume it's the pipe.

Check cam timing.

I'll pull it tomorrow. Everything seemed fine.

Check coolant level, if low, and not attributed to overflow or a hose leak.. and you are seeing vapor out the exhaust,, you have a head gasket leak.

Coolant is about the same. I drained the oil. It looks a few shades darker than the oil I put in. It's not milky.

Re install the ACCT for now, solve other issues first, then come back to the CCT.

Bike didn't come with an ACCT.

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It seems a lot of people have issues with the bike dying after 10 minutes and not restarting. This seems to be caused by a fuel issue. I'll look into a few suggestions tomorrow. Breather hose, vacuum and a few other solutions. I may need to switch to a manual petcock.

I'll take a video with sound tomorrow of the engine. Perhaps I'm imagining things.

Oil looked good, coolant was good.

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It seems a lot of people have issues with the bike dying after 10 minutes and not restarting.

Mostly only those with a CA smog bike.

The emission gas vapor charcoal canister get soaked with raw fuel and then doesn’t vent.. OR the vent line that goes to that same item gets pinched...same result.

NON CA bikes, the tank vents though the cap.. never seen one of those get plugged up, though Im sure someplace it has happened.

If that is your issue, open the gas tank cap... and or, pull the fuel line form the carb,, if it flows gas, that is not your problem.

And other times it is fuel contaminated oil.. when that oil heats op, the fuel vaporizes reenters the intake system and causes run ability issues.

You have had some much going on with your build, coupled with your learning as you go.. Is is difficult to know what might be wrong and where to start with suggestions.

Is the piston seizing in the cylinder/ what was the clearance measured prior to install?

You used a set of replacement rings,, did you fit them// what was the end gap?

The piston and cylinder have been on and off a few times.. the cam chain worked on and around,, is the cam timing right? Was it right each time the motor was together and turned over?

What are the valve clearances?

Is the gas fresh? Is it contaminated with fuel?

You said something about the head gasket “Head gasket has been used once, copper coated torqued to 34 or so at first, then 43ft like suggested.”

Just to be clear… Used ONLY ONCE TIME… .it has only been installed once, not installed, then the top end taken off for more work, then installed again.. Yes? NOT asking if it was run more the once, .. And not trying to drag this out,, just keeping things clear for others to understand and help.

Iit was placed on the head / cylinder only once, TQ’ed to spec only once, ran, and now your where you’re at with the issue above.. Yes?

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