Cylinders are off . . .

[skids]

"A few of the intake valves were tight, but what REALLY made me nervous wad the clearance on exhaust valve #3 was .30 mm. Never seen my clearances that out of spec. I'm thinking bent valve . . . compression check across all four cylinders was 120 psi (you'd think new rings would have gave me a higher compression number?) So, at-least I have compression. "

.30 is really not enormous, but needed adjustment. 0.24 is the max for exhaust, I think. One shim size will get you on the fringe of the range, and that would be on the good end of the range. Yeah, you need to break it in and I think those compression numbers will come up. If it was me, I would break it in before storage.

[TopCatGr58]

Hey Ian,

Congrats on the safe assembly. As to the comp levels, remember, the rings are not seated/broken in, and so of course you'll have some pressure leakage past them, therefore less than spec for now is expected. Once it's broken in, then you should see much better specs. As for the large clearance value, you bent valves, put in new ones, so you have new thick valve heads and shoulders, even after grinding, possibly still thicker so the shaft of the valve doesn't stick up as far into the head=larger gap to shim, remember, the gaps narrow with wear, but you've restarted with new valves.

T.C.

[IanDMacDonald]

If you take a cylinder head to a machine shop, also take the cams so they can set the valve lash. Saves you that task.

Given the info that you posted, it is time to start it, tune it, and ride it.

I didn't. I just took the cylinders for a bore job.

[IanDMacDonald]

Hey Ian,

Congrats on the safe assembly. As to the comp levels, remember, the rings are not seated/broken in, and so of course you'll have some pressure leakage past them, therefore less than spec for now is expected. Once it's broken in, then you should see much better specs. As for the large clearance value, you bent valves, put in new ones, so you have new thick valve heads and shoulders, even after grinding, possibly still thicker so the shaft of the valve doesn't stick up as far into the head=larger gap to shim, remember, the gaps narrow with wear, but you've restarted with new valves.

T.C.

Huh? Lol. I presume you're referencing my previous bent valve escapade? No bent valves this time around T.C. (hopefully).

In all fairness, it may have been a few years since I checked my valve lash. I left everything tight. I figure the engine will get pulled to re-paint in the future, and it would be a good time to do the valve lash again. The reason I left them tight was out of all the shims I have, I did not have the one's I needed. It can wait.

[Radioguylogs]

TC's point is that you have new valves (we know that because you bent some before).

The new valves have a fresh surface around the perimeter of the valve head. With no wear, they would not sit as deeply as a worn valve. Therfore more clearance might be expected.

I think your point is that the shims were tight after you put in new valves, so the new result is strange to you?

[IanDMacDonald]

I think your point is that the shims were tight after you put in new valves, so the new result is strange to you?

Correct, Mike. A few years ago when I bent the intake valves, the machine shop set the lash.

Now, a few years later, I check the valve lash again, and that one being out of spec stuck-out to me, as in all the years I've checked lash across all of my bikes, I've never had a valve that out of spec, which made me think "bent valve". I swapped the shim out with a larger shim, and it tightened the gap up (of course too tight).

[IanDMacDonald]

All Done for now . . .

After many strings of colorful words, exhaust, carbs, airbox are back on.

I debated on starting the bike, as the Startron bottle was empty. I decided to start it anyways. It would not stay running without my hand on the throttle, and the carbs leaked (that was expected, and had rags ready to catch the gas).

I varied the idle between 1k and 2.5k rpms. I didn't want to rev it, as I've never broke-in a rebuilt engine before. So, I observed one smoky engine from the rtv and the custom exhaust nuts that had high heat paint on them. I turned the gas off, started it till there was no more gas in the lines, and shut it off.

Come Spring, I'll change the fluids, change the tires, and pull the carbs and give them a good clean.

[TopCatGr58]

Congrats on ensuring that it would at least fire and run. If it's going to take a long winter nap, I would put a bit of oil down each spark plug hole and hand rotate the engine a couple of cranks to get it spread all around. You don't want any humidity and an open valve letting it flash rust on a freshly honed cylinder!

T.C.

[DiverRay]

Use a bit of SYNTHETIC oil, or if you have it some fogging spray for boats. Either will insure all the steel is coated, and stays that way.

[IanDMacDonald]

Use a bit of SYNTHETIC oil, or if you have it some fogging spray for boats. Either will insure all the steel is coated, and stays that way.

I'll buy some from Walmart later today. Thanks for the tip. Sucks I can't just ride it to storage, but I feel trailering it is the best idea, especially with leaky carbs, un-bled front brakes, and rings not broken-in.