Reunited with XS650SH

[jetmechmarty]

My rule of thumb.... if you're not sure, treat it as detonation.
Kinda like when I lived in places with King and Coral snakes....

Instructor: the color bands are ordered different... it's easy to tell the difference.
Me: don't give a fuck, they're ALL coral snakes far as I'm concerned.
Instructor: learn the difference or fail my course.
Me: least I ain't gonna screw it up and die if I go with my plan.

*actual conversation I had...

All this is likely why I found it with B7ES spark plugs in it.

 

[Jim]

All this is likely why I found it with B7ES spark plugs in it.

Could very well be. But treating the symptom rather than the underlying cause isn't the best way to do things.

Edit: Actually, 7 is the correct heat range... so not sure if the wrong insulator was intentional or not...

 

[Paul Sutton]

I did not read the full thread but my US XS650SH did not have a number stamped on the chassis/frame. Instead the chassis number was on the sticker stuck to the head stock just out of view beind the headlight.

Nice bikes those Specials of your, especially with them handle bars. For me they are so comfortable, but not everyone agrees.

Enjoy them...

 

[jetmechmarty]

I did not read the full thread but my US XS650SH did not have a number stamped on the chassis. Instead the chassis number was on the sticker stuck to the head stock just out of view beind the headlight.

Nice bikes those Specials of your, especially with them handle bars. For me they are so comfortable, but not everyone agrees.

Enjoy them...

This bike has a factory replacement frame. It has no VIN and no decal. The bike was wrecked with 13 miles on it.

One Special has factory Special bars. The other has Emgo Triumph T140 replica bars.

 

[Adamc]

 

[jetmechmarty]

??

 

[Paul Sutton]

Oops! Crashed after 13 miles...

 

[jetmechmarty]

Oops! Crashed after 13 miles...

It got crunched by a car while parked in the garage is what I was told.

 

[joebgd]

What if there where little pieces of aluminum stuck to the plug? Edit what would that tell? Is it only aluminum can other metals get inbeded on plugs?

 

[jetmechmarty]

What if there where little pieces of aluminum stuck to the plug? Edit what would that tell? Is it only aluminum can other metals get inbeded on plugs?

It would say I’m too hot and I’m melting the pistons. There shouldn’t be other metal the piston will have a hole in it before it gets that hot. The XS650 has a steel combustion chamber.

 

[Jim]

What if there where little pieces of aluminum stuck to the plug? Edit what would that tell? Is it only aluminum can other metals get inbeded on plugs?

Little aluminum balls are from the piston... that is... if that's what they are. They're precursors to holes in the pistons.

 

[jetmechmarty]

Little aluminum balls are from the piston... that is... if that's what they are. They're precursors to holes in the pistons.

I suppose those little flecks could be carbon formerly deposited in the combustion chambers. The carburetors were not set up properly. JAT

 

[jetmechmarty]

The 1975 Triumph on the right in the top picture was the inspiration for the handlebar on the SH. The photo was taken in 2001. My friend still has the 1975 Bonneville. The 2001 was sold just recently and replaced with a new T120.

 

[jetmechmarty]

I changed the pilot air jets to #130. I changed the main jets to 137.5. This was the @5twins recommendation. This thing is exceptionally easy to start.

Below is a picture of what my timing is at idle. In the circle. I understand that to be 35 degrees. The red line is a guesstimate, but that's about where the maximum advance is. I'm not sure if this is perfect or way too advanced. With it so easy to start I have doubts about how advanced it is.

Thanks for the filter tips @Vincenthdfan @gggGary

 

[jpdevol]

On your timing (looks good): the 'U' mark is ~15*, the cover drain groove ~38* , you appear to be ~40* at the red line

 

[Jim]

Below is a picture of what my timing is at idle. In the circle. I understand that to be 35 degrees. The red line is a guesstimate, but that's about where the maximum advance is. I'm not sure if this is perfect or way too advanced. With it so easy to start I have doubts about how advanced it is.

 

[jetmechmarty]

View attachment 240082

I’ll double check tomorrow, but I think 40 degrees is about right. I’ll give it a go and see if the pinging is fixed and hopefully, a bit of color on the plugs.

Thank you, gentlemen!

 

[5twins]

I believe the center of the "U" is 15°. That would make it's right leg, where you're set, about 13°, and I think that is ideal. That would move the full advance from 40° (15° idle timing + 25° of advance) to 38° (13° idle timing + 25° of advance). That should cure the pinging if it was timing related. If it was lean carburation that was causing it, hopefully the jetting changes you made will fix it.

 

[jetmechmarty]

I did not alter the timing.

The aftermarket petcock has a 3/16” outlet. I assume it’s big enough, but stock is 1/4”.

 

[5twins]

I thought that normally, the factory would set the timing at the middle of the "U", at 15°. It doesn't look like your timing plate has been moved (factory paint on the mount screw looks undisturbed) but eventually, you may want to verify the TDC mark. If it's off, the "U" will be too.