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-   -   Doing a little surgery: (http://forums.pelicanparts.com/showthread.php?t=1089446)

speeder 06-05-2021 11:12 PM

Ok, just to make it more interesting:
 
The stock bore on the bike is 71mm, (650cc). The P/Cs I'm installing are ~76mm, (750 kit). The combustion chambers are around 69.5mm, meaning that quite a bit if the border of the piston will be under the flat part of the head that does not have piston under it with stock pistons. Looks to me like I might still have a decent CR but a really weird squish band...not sure what the implications of that are, performance-wise.

I really need to find out if all of the kits are like this and whether there is an engineering explanation(?) Pictures tell the story better than I can:
http://forums.pelicanparts.com/uploa...1622959794.jpg
http://forums.pelicanparts.com/uploa...1622959794.jpg
http://forums.pelicanparts.com/uploa...1622959794.jpg
http://forums.pelicanparts.com/uploa...1622959794.jpg

speeder 06-05-2021 11:28 PM

And here are a few photos, out of order, of installing the cylinder block:
http://forums.pelicanparts.com/uploa...1622960619.jpg
http://forums.pelicanparts.com/uploa...1622960724.jpg

Special Triumph ring compressors: ;)

http://forums.pelicanparts.com/uploa...1622960823.jpg

DonDavis 06-06-2021 08:37 AM

So tidy, so clean. Nice work.

speeder 06-06-2021 08:51 AM

Thank you, Don.

speeder 06-10-2021 12:50 AM

Here are some progress shots, it should be back on the road this weekend. To be continued:
http://forums.pelicanparts.com/uploa...1623311354.jpg
http://forums.pelicanparts.com/uploa...1623311354.jpg
http://forums.pelicanparts.com/uploa...1623311354.jpg

Bill Douglas 06-10-2021 12:57 AM

Good skills! It all looks so nice and clean and orderly.

I'm sure it's going to be a huge success.

Skip Newsom 06-10-2021 08:02 AM

Great stuff Denis!!
Thanks for the updates, you are making me start thinking again about the seized 750 waiting patiently under cover in my Caveman Shop.

But first I still need to reassemble and wire it in it's current configuration.
Dropped off the motor to frame corner brackets, rear hub stay and swing arm at a local sandblaster yesterday, pick it up and paint it in a couple hours.

Projects, projects... so far this year we renovated the kitchen and dining room, had the exterior of the house painted, new gutters are scheduled, back yard renovation is scheduled, helping a buddy with a Gazebo build, and I'm overdue for a kayak thrashing...
Glad I've got stuff to do, keeps me happy!

unclebilly 06-10-2021 03:27 PM

That squish band is nothing to worry about. What do you think your head gasket does?

If you are worried, go to a large animal vet and get some 60 mL syringes and cc the head and piston (at BDC and then subtract off the stroke X area. Figure out your CR.

I did this on my 911 and shimmed my heads to give a 9.8:1 CR with 9.5:1 pistons. 9.8 is supposedly the max you can go without twin plugging.

This looks likea great build.

speeder 06-10-2021 04:21 PM

Thanks. I wound up getting my concerns addressed by a visit to the Triumph shop that has been helping me. They showed me a stock 650 with the head removed and it was worse!! :D

Just the way these motors are, I guess. And I also needed to be shown that the clearance of the dome of piston to chamber was much greater than squish band, that is what matters.

I'm wrestling with the pushrod tube clearance/squish right now before torquing head down but I hope to have it all together this weekend. There is a lot more to assemble than the engine but it's coming along. :)

speeder 06-17-2021 11:01 PM

Coming together
 
As time allows...
http://forums.pelicanparts.com/uploa...1623995653.jpg

speeder 06-18-2021 11:22 PM

http://forums.pelicanparts.com/uploa...1624083552.jpg
http://forums.pelicanparts.com/uploa...1624083552.jpg
http://forums.pelicanparts.com/uploa...1624083552.jpg

speeder 06-19-2021 10:55 PM

Got it done!
 
Put the rest of it together yesterday and today, no left over parts! Yay! :)

I bet my buddy that it would start on the second kick and sure enough, it did! One kick to suck in some fuel and then, vrooom! Sounded really good but I shut it down immediately because I'm going to break it in tomorrow on some hills. I have break-in oil in it, (30w non-detergent), I just needed to confirm that it was going to run before I truck it to the hills.

Happy to be done for now, (hopefully). :)

http://forums.pelicanparts.com/uploa...1624168357.jpg
http://forums.pelicanparts.com/uploa...1624168357.jpg

craigster59 06-20-2021 07:11 AM

Great job Denis! She's a beauty! Maybe take it up Mt. Pinos to beat the heat.

speeder 06-20-2021 09:28 AM

Thanks! As for the heat, it's strange...I'm reading about a heat wave in the Times but it hasn't been crazy hot in LA at all. The high today is 77, according to my phone. The last few days were hotter for sure but nothing extreme for summer.

Living in coastal CA. has its perks, until it doesn't. ;)

herr_oberst 06-20-2021 11:39 AM

This is beautiful. I can imagine Peter Egan writing a story about fixing up an old Bonneville. Oh yeah, I'm sure he did! Enjoy that classic, you lucky bastage!

speeder 06-20-2021 10:30 PM

First break-in/shake down run:
 
Just got done thrashing it around Laurel Canyon to break-in the rings with ND 30w oil in it, engine feels great with good compression and torque. Such a fun bike to ride on twisty roads. I brought it to my friend’s house in my truck in order to use the hills for break-in. I have my own little protocol and it’s served me well with many engine rebuilds on various machines. There isn’t a flat or straight road in Laurel Canyon, so it was perfect and fun. :)

A couple of hours ago:
http://forums.pelicanparts.com/uploa...1624250717.jpg
http://forums.pelicanparts.com/uploa...1624250717.jpg

Bill Douglas 06-21-2021 12:24 AM

There isn't a large pool of oil under it, so it appears you have won. - congrat's.

1990C4S 06-21-2021 06:48 AM

Quote:

Originally Posted by Bill Douglas (Post 11367854)
There isn't a large pool of oil under it, so it appears you have won. - congrat's.

He might be draining it after every drive...

Nice job on the bike. That looks like a very rewarding project.

speeder 06-21-2021 09:10 AM

Quote:

Originally Posted by Bill Douglas (Post 11367854)
There isn't a large pool of oil under it, so it appears you have won. - congrat's.

Fingers crossed but it doesn't seem to be leaking anywhere. I took a lot of care with assembly and surfaces, etc., to make it tight. Interestingly enough, the split case design on Triumphs is actually really good...unless you really slob that part of the build, they should not ever leak out of the case itself. Top end and pushrod tube leaks are the common ones.

I cleaned the case halves really well and put them together using Loctite 574, the recommended sealant for air-cooled 911 cases. My friend Tyson Schmidt supplied the Loctite and the expert touch with application, really appreciate him. You can see the "ridge" on one of the case halves that really locks them together when they mate. Should not ever leak:

http://forums.pelicanparts.com/uploa...1624291655.jpg
http://forums.pelicanparts.com/uploa...1624291655.jpg
http://forums.pelicanparts.com/uploa...1624291655.jpg
http://forums.pelicanparts.com/uploa...1624291655.jpg


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