Shovelhead Cylinder Gasket

[AbbandonZK]

I decided to take apart my cylinder heads to re-align my intake and deal with the leaking rocker box gasket.



I'm getting carb pops when I take off after just starting the engine warm or cold. Also the engine will just randomly die when idling. I upped to a .031 from a .0295 on my super e and the poping went away but the plugs were mega sooty.

I got the heads off and I didn't even need to use a mallet.




I was getting vapor in the oil tank and a whooshing noise out of the pushrod tubes but I didn't think much of it.

I did a gas test on the valves and only the front exhaust valve trickled gas. I haven't taken the valves apart yet. The last valve job I had done was 600 miles ago in last year September.

Should I re-lap the front exhaust valve?

[AbbandonZK]

The cylinder wall don't have any indication of gouging.


The bike only has good compression when its hot. I've latley needed to give it a squirt of fuel or use the choke to get it going when hot. If it don't it cycles twice and then dies.

[Dragstews]

Shoot, ya got it down this far, why not re-ring it ... ?

[AbbandonZK]

Shoot, ya got it down this far, why not re-ring it ... ?

The engine only has 632 miles on it I finished building the bike in September. Should I re-ring them?

[Dragstews]

Don't see much of a hone pattern for being so little miles...

Judging from what I see, it would be a good bet to say if you had done a leak-down test you would see at least 30% or more leakage going by the rings ...

[AbbandonZK]

Don't see much of a hone pattern for being so little miles...

Judging from what I see, it would be a good bet to say if you had done a leak-down test you would see at least 30% or more leakage going by the rings ...

When inspected the jugs during the build they had a hone pattern in them. I might be able to get base gaskets from a local shop and a cylinder honer from Harbor Freight. Will the rings be reusable if the bore gauge says the cylinder walls are still within spec?

[WillSCB]

Among other things, the first problem I see is the teflon head gaskets. Throw those worthless pieces of shit in the trash and spend the money for a decent set. I could never get those to last more than about a week.

[armand]

Don't see much of a hone pattern for being so little miles...

Judging from what I see, it would be a good bet to say if you had done a leak-down test you would see at least 30% or more leakage going by the rings ...

Drag , what could have happened to the hone pattern? Wore away (too quickly)? Not honed enough initially?

[AbbandonZK]

[JBinNC]

Your cylinders look like they were ball honed, or honed with a glaze breaker when the rings were replaced. Not ideal but acceptable. A better choice is to hone them with a micrometer adjustable cylinder hone, Sunnen, Lisle, or the like. I would gladly give up .0005 - .001 skirt clearance for better cylinder wall finish.

I think you just need to replace the shitty head gaskets with some decent fire ring gaskets and put it back together. And don't ever use those blue gaskets again. And torque yer head bolts to 60ft.lb.

Jim

[Dragstews]

Fairly light pattern, and just a bit flat in those photos ...
But I'm seeing two ware patterns at the top of the bore for ring travel, this could denote a broken top ring ..??

Do you recall what the ring gap was set at ... ?

[AbbandonZK]

Fairly light pattern, and just a bit flat in those photos ...
But I'm seeing two ware patterns at the top of the bore for ring travel, this could denote a broken top ring ..??

Do you recall what the ring gap was set at ... ?

I don’t remember but I always aim for the low end of the acceptable range.