PHANTOM RESURRECTION 78 SPECIAL

If you clean the top of your good piston off, you'll find a 3 digit number stamped on it .....

CleanPiston3.jpg


This was the fractional portion of the piston size when new, as in 74.xxx mm. The one pictured above would have been 74.953mm when new. Probably best you find a replacement at least as big as the one you have now.
 
5twins said:
If you clean the top of your good piston off, you'll find a 3 digit number stamped on it .....

View attachment 252444

This was the fractional portion of the piston size when new, as in 74.xxx mm. The one pictured above would have been 74.953mm when new. Probably best you find a replacement at least as big as the one you have now.
Click to expand...
It’s so awesome to have a resource to find these kind of details.
 
5twins said:
If you clean the top of your good piston off, you'll find a 3 digit number stamped on it .....

View attachment 252444

This was the fractional portion of the piston size when new, as in 74.xxx mm. The one pictured above would have been 74.953mm when new. Probably best you find a replacement at least as big as the one you have now.
Click to expand...
Yeah, the one with the hole punched in it by the stuck valve probable had the numbers smacked. Thank again
 
An easy way to clean the carbon off is to just use plain old paint stripper. It will "melt" the carbon away and greatly reduce the amount of scraping needed. It may take a couple applications and soaks to get it all .....

Stripper1stAppl4.jpg


Here's that 1st application scraped .....

1stApplScraped2.jpg


Then a 2nd application scraped .....

2ndApplScraped.jpg


I finish by using chrome cleaner .....

CleanPiston2.jpg


The paint stripper also works well for removing the old stuck on gaskets. You're going to especially find the gaskets for the points and advance housing stuck on real good because Yamaha using sealer on them. A couple soaks and scrapings will get them off pretty easily. The first soak will most likely only soften partway through the gasket .....

Stripper1stAppl3.jpg


1stApplScraped3.jpg


But a second soak should get most of it off .....

2ndApplScraped2.jpg


A few dabs of stripper on the remaining bits will finish the job.
 
I just want to check in. Which vendor do I buy an exhaust valve from. The machine shop is ready to install it. The cylinders are honed, valve seats dressed. I just need to get him a valve.
 
Hello all Yamahamians! I know, it’s been a bit since I last queried but I’m back. Thanks to all for the exhaust valves and side covers.
I’ve got rings on the way and about to slap it back together. I’m wondering about a gasket/ seal kit that allows me to reassemble the top end. I specifically need the four grommets that go on the studs after the rocker arm assembly before the head nuts. I kind of want the seals in case I have a catastrophic leak when I start this bad boy for the first time in 35 years. Any suggestions?
Thanks again.
Also, my voltage regulator has no cover.
 

The Phantom said:
I specifically need the four grommets that go on the studs after the rocker arm assembly before the head nuts.
Click to expand...
Sounds like you're describing the sealing washers that are originally a rubberized washer. Personally I prefer brass sealing washers there as they retain torque on the head nuts better

Original style
https://www.mikesxs.net/yamaha-xs65...0210-10004-92990-10200-00-90210-10004-00.html

Brass Head washers
https://www.mikesxs.net/yamaha-xs650-brass-cylinder-head-washer-oem-90210-10004-00.html

Vesrah Top-End gasket kit
https://www.mikesxs.net/gasket-set-complete-xs650.html
 
jpdevol said:
Sounds like you're describing the sealing washers that are originally a rubberized washer. Personally I prefer brass sealing washers there as they retain torque on the head nuts better

Original style
https://www.mikesxs.net/yamaha-xs65...0210-10004-92990-10200-00-90210-10004-00.html

Brass Head washers
https://www.mikesxs.net/yamaha-xs650-brass-cylinder-head-washer-oem-90210-10004-00.html

Vesrah Top-End gasket kit
https://www.mikesxs.net/gasket-set-complete-xs650.html
Click to expand...
Thanks, I agree the brass sounds better
 
jpdevol said:
Sounds like you're describing the sealing washers that are originally a rubberized washer. Personally I prefer brass sealing washers there as they retain torque on the head nuts better

Original style
https://www.mikesxs.net/yamaha-xs65...0210-10004-92990-10200-00-90210-10004-00.html

Brass Head washers
https://www.mikesxs.net/yamaha-xs650-brass-cylinder-head-washer-oem-90210-10004-00.html

Vesrah Top-End gasket kit
https://www.mikesxs.net/gasket-set-complete-xs650.html
Click to expand...
Thank you so much for this information... I want check....
 
If your carbs are the originals, they would be Mikuni BS38s, not 32s. The original manifolds had vacuum nipples on them to power the petcocks. They're not as easy to find as the plain ones. But, you can add the vacuum nipples to the plain ones if that's all you can find.
 
5twins said:
If your carbs are the originals, they would be Mikuni BS38s, not 32s. The original manifolds had vacuum nipples on them to power the petcocks. They're not as easy to find as the plain ones. But, you can add the vacuum nipples to the plain ones if that's all you can find.
Click to expand...
My mikuni 32 no original
 
Fabio raffa said:
My mikuni 32 no original
Click to expand...
What do you mean by “power the petcocks”? I have to nipple manifolds intact. They weren’t connected to the petcocks though when I got this bike.
Also I got new rings for the pistons. One silver colored the other black, then the oil ring combination. Which ring goes where for compression?
Thanks
 
Fabio raffa said:
My mikuni 32 no original
Click to expand...
What do you mean by “power the petcocks”? I have two nipple manifolds intact. They weren’t connected to the petcocks though when I got this bike.
Also I got new rings for the pistons. One silver colored the other black, then the oil ring combination. Which ring goes where for compression?
Thanks
 
Last edited:
I think the silver/chrome ring is the top ring.
Look closely at the compression rings if they have a dot or number on one side that side faces up.
 

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