The Patience build.

Lol can’t walk away for a minute, the replacement for this came today with my other items. 343C1C19-1262-4AD5-B3D5-74313868DE49.jpeg
 
With tags in place we went out for a break-in ride and as expected there are still things to work on. Flasher went out, I heard some buzzing and now I have signal lights but they don’t blink. Front suspension on this bike is stiff! I might just be used to more modern cruisers but I made sure I raised up on tracks or bumps. I appear to have done a good job balancing my rear tire but the front not so much lol. Got rain coming so that’s coming back off. It’s just subtle enough to drive me nuts! Everything else appears to be ok. No leaks or rattles just the nuance of riding a 46 yo machine which wasn’t very state of the art at that time much less today. The seat is pretty comfy though……now If I can just retrain myself to cancel the blinkers and turn off the gas when done…..
 
Got about 45 mi or so and the rings still haven’t sealed I can definitely tell the difference in the ring sets the ones I got from Cruznimage gave me problems from the beginning, thus the OEM set that I quick ordered when one of the original sets got messed up. OEM side is not smoking as much but still doing it also. Had a good crosshatch in my cylinders.Any suggestions other than Ajax or Baking soda? Lol
 
Got about 45 mi or so and the rings still haven’t sealed I can definitely tell the difference in the ring sets the ones I got from Cruznimage gave me problems from the beginning, thus the OEM set that I quick ordered when one of the original sets got messed up. OEM side is not smoking as much but still doing it also. Had a good crosshatch in my cylinders.Any suggestions other than Ajax or Baking soda? Lol
Fwiw, my Cruzin rings seated with no problems at all.

As far as what to do, take it out and run the piss out of it. Best and fastest way to seat rings that I know of.
 
Yea Jim the set I put in the ‘72 motor that I got from him didn’t take anytime to seat either. Been too damn hot the last couple days to go out but this weekend it’s supposed to be nice. My front wheel has a small issue also. It feels like it’s out of balance but I took it off and static balanced it with it being fine and I checked for out of round and that is very minute. Ring tested my spokes and they are all in tune and it’s not a wobble but def up and down so I might take that in and have them spin it on a machine.
 
I didn’t want to ride anymore until I got that front wheel issue resolved. I could not understand why it felt so out of balance. I figured the wheel just wasn’t right from me replacing the spokes so I built another truing stand pulled the wheel off and just started adjusting. I thought that originally I had it pretty good but may as well see if I could get it any better. F860803A-DD33-4959-8EA5-871512FC564E.jpegIt was actually pretty good as I though but why did it feel like it did? I was actually to the point I was checking things with a caliper and I noticed something about my tire. There was one small area where the bead hadn’t popped completely out. Hopefully I found the issue.F4E63369-859E-408F-9891-5FCD1D32C3B9.jpeg175BE122-E694-4CD9-844B-1BCE2EC9E726.jpeg
 
Whatever it was either me tweaking spokes or reseating the tire seemed to have improved things drastically. Rings appeared to improve as well but still getting a small bit of oil smoke so hopefully they are seating.
 
I’m pretty sure something is going on besides a ring seat because I ran a compression check and it’s strange to me but I’m pretty sure it’s accurate. So the cylinder that’s having ring issues is running about 128 psi on the gauge. The cylinders that appears to be seating is running 78 psi. So right cylinder low psi, no smoke, left cylinder good psi and smoke. In any case I’m going to pull that motor again and do some checks. I’m not worried about it at this point as I want this to be right and my haste to try and finish this bike while at my Dads has probably led to about 99% of my issues. On the bright side I only have to do the top end, everything else on the bike is done so I won’t be down long once I gather a few more parts. Since the head gasket has so few miles on it do you guys recommend replacing it or reusing. I have an extra gasket set so no worries about that other than it’s the dreaded green Athena.
 
I've always replaced the head gasket once it's been crushed down.
 
@Jim gave good advice for a no fail repair as far as the head gasket. On my spare motor I didn't replace the cam chain when I rebuilt it and lived to regret it. When I pulled the engine to replace it I did not separate the head from the block, I left the 3 small bolt tight that go from the the head to the block. Replaced the chain, installed cam cover, torqued the head back down and put back in bike. Ran great with no problems. Only reason I took it back out was to put the BBK engine in. I rolled the dice and won you may not.
 
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My theory was by not removing the 3 small bolts the head gasket would not be disturbed. Just the compression on it would be removed. Kinda like when you retorque the head.
 
That would be great except I have a feeling that low pressure is from the valve I replaced so head does have to come off. It’s not that big of a deal. Even if I didn’t have a spare gasket I would get one. I usually already know the answer to the questions I ask I just like somebody else to say it. Lol
 
Got another set of rings coming tomorrow so I got the engine pulled back out and prepping. I was wrong about the valve leaking. I should have known that. For one thing the valve I replaced was on the good side lol and I did a leak check wit the head off and no issues so it had to be the rings. I checked the cylinder and it mic’d at 2.950 and the piston was 2.935 so not being totally savvy with all that I’m assuming that’s pretty close. Ring gap was .028. I even looked to see if I missed a top and bottom of the rings but they have no markings and are square edged. All I can do is put it back together and hope it does what it’s supposed to.9C8F4561-1FF4-4AF2-BC54-3EC6E2C252C3.jpegAE8E5C95-F1CD-40DC-8967-D9D9F06A9626.jpeg
I do know that new cam chain was a bitch to get off that cam without separating it.
 
cylinder and it mic’d at 2.950
Factory spec on the cyl's is 2.9528 +.0008 -0.
I suspect your measurement's off. No way they shrunk smaller'n what the factory cut 'em to. ;)

Ring gap was .028
First and second ring gap is 8 to 16 thou. Yours is almost twice that.

I checked the cylinder and it mic’d at 2.950 and the piston was 2.935 so not being totally savvy with all that I’m assuming that’s pretty close.
No, not close. That would give you about 15 thou skirt clearance. Book max is .0022" .....though it's normally accepted practice to go as high as .004" when reusing old pistons.
 
Thanks Jim for clarifying that. Like I said, I’m not used to working with that close of a tolerance so this is a learning process and yes I’m sure my measurement was off, hell I’m lucky I got that close as that mic has been in my drawer for years and been used maybe a half dozen times to check seal clearance and that’s about it. Before I retired my Forte was being the guy who could decipher detailed architectural drawings, but that was geometry in feet and inches not thousandths. 😉
Factory spec on the cyl's is 2.9528 +.0008 -0.
I suspect your measurement's off. No way they shrunk smaller'n what the factory cut 'em to. ;)
Geez, I only missed by .0028……

First and second ring gap is 8 to 16 thou. Yours is almost twice that.
Could that have been the issue with that side smoking and lack of compression?

No, not close. That would give you about 15 thou skirt clearance. Book max is .0022" .....though it's normally accepted practice to go as high as .004" when reusing old pistons.
I’m just trying to get this old girl on the road and reliable. I had no issue pulling that engine back out and trying again. I had minimal issues building my ‘72 engine so maybe it’s sometimes better to be lucky than good.
 
I also looked back at my previous posts. I gave bad info as to which cylinder was doing what. After pulling it apart all issues were on the left side. Bad rings, low compression.I guess I had the head upside down and backwards when I was putting it together so I thought it was opposite. New valve and OEM rings are on the right side. Now I have OEM for the left so let’s see what happens. Rings actually showed up today.
 
"Could that have been the issue with that side smoking and lack of compression?"

Doubt it had much to do with the smoke unless the oil ring gap is too big also but yeah, compression would be down a bit.
 
So like I said, sometimes you get lucky! $15 on eBay and a Mi seller so they got here in two days. Checked the gap and with these it’s .014. Rings have chromed edges so I’ll replace both sets and see what happens. I’m gonna check and see what the OEM Yamaha rings measure.D88A94A3-51A6-47A6-9559-55DD5CE148D7.jpeg147C705A-85DB-4775-8F98-71DF12F7A7B7.jpeg
 
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