What have you done to your XS today?

Crank spins twice for every cam revolution so isn't the base timing doubled?
Yes. 180° rotation at the cam gives 360° at the crank. Think of it this way... 14° of cam rotation would give you 28° at the crank. Think of the 14° advance, as 14° cam rotation. The crank would have moved 28°
 
Yes. 180° rotation at the cam gives 360° at the crank. Think of it this way... 14° of cam rotation would give you 28° at the crank. Think of the 14° advance, as 14° cam rotation. The crank would have moved 28°

Got it... kind of strange there really isn't any conversation about actual timing numbers.
 
Well for advance, you want the 25° 5twins said above. So you're about 3° over. You could play with the advance mechanism to take that out or just back your idle timing down by 3° That wouldn't hurt anything and would likely be the easier option.
 
unpacked new tank - ordered on 4th of July!

D06384D8-5B32-489C-AD98-E4609DE6FC41.jpeg


couldnt resist setting it on the backbone - gonna order the stuff to mount it properly, already have 3/8” Pingel race taps ready to install...

now I can finally start subframe fab.
 
Silly question Mr. Iron horse, I guess you're spinning the advance timing by hand, to see how many degrees it rotates?
I continue to mess with my mechanical advance system. Yesterday I tig welded some steel "shims" onto the stop tabs, to reduce the distance the weights will fly out. I am now using a dremel grinder to reduce the thickness of the shims until I've got it right.
I've been screwing with this setup for the last few months. The brand new XS650direct replacement for $75 didn't solve the problem of advancing too much. Gluing with epoxy shims to the stops did fix it and a few weeks ago it ran better than ever, then the snow came...
I've already peened the little pieces of the weights each did reduce slop
 
Sweet fairing! Considering it's not real unless there is a photo, this is what I'm installing. Will see how it works out! I may have to reduce the thickness of these new stops a bit more.
 

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Silly question Mr. Iron horse, I guess you're spinning the advance timing by hand, to see how many degrees it rotates?
I continue to mess with my mechanical advance system. Yesterday I tig welded some steel "shims" onto the stop tabs, to reduce the distance the weights will fly out. I am now using a dremel grinder to reduce the thickness of the shims until I've got it right.
I've been screwing with this setup for the last few months. The brand new XS650direct replacement for $75 didn't solve the problem of advancing too much. Gluing with epoxy shims to the stops did fix it and a few weeks ago it ran better than ever, then the snow came...
I've already peened the little pieces of the weights each did reduce slop

Correct just spinning it by hand to check the advance. The stock 14 is too much, I just bent the tabs and reduced it to 10 degrees.
 
I keep getting distracted on really nice weather days. Replaced the rechargeable 3v battery in my 19 yr old BMW key. Did multiple other things AND replaced my kick start mechanism in about 1 min. That said, lol, spent over an hour polishing that shaft where the case seal goes; taking apart k.start arm, cleaning about 50 yrs out of the swivel, b-bearing all the splines...bit of lube. Checked that function by slowly turning Kick from 12 o'clock to somewhere past 6 o'clock, watching the engine rotate slowly...pushing down a bit on kick shaft and letting the spring return it under tension back to 12...seeing the the screw brought the shaft gear back up clear of it's mate gear...Been up > 11 hrs. Going to replace the clutch early AM tomorrow. I guess that's next. Humm, 3 Hi-po Barnett springs and the rest from the ones in the clutch for ever? Or all Barnett's? I'll toss a coin. Not going to be putting mucho miles on this bike. I sat on 2021XSR700 at the dealer last weekend :heart: and dreamed of *not* killing myself on the XSR900 :bike:
 
OK,took a while but found the new needle bearing n washer for the 256 clutch, found one b-bearing labeled 7.90 mm, found other still stuck in worm hole.. since the newish looking factor seal for clutch rod...looks real good (from prior rebuild) I'm ordering a new long rod from Mike's XS. I After brushing ends of this orig. long rod, I see fine pitting on 2.5 " of machined end and my finger nail swears it feels something on the grey seal end...and I used all the HD springs. $15 peace of mind. Clutch pack installed, rod and BB's later...beautiful day to try and start loosing 10 lbs (walking riding bicycle) and some elbow grease on 2 engine covers and 2 wheel hubs while breathing the nice clean Fla. air. I think getting the ancient tires off will be a pain even with a knife, saw n bead cutter.
****Actually, I'm going to deflate these 1970's tires..forgot I have some long metal tire irons and I'll remove tires to ensure only I am responsible for any steel rim damage (none). Get the original spoke off , then clean the alloy hubs..and rear brake.
 
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Correct just spinning it by hand to check the advance. The stock 14 is too much, I just bent the tabs and reduced it to 10 degrees.
@grizld1 (and Yamaha in a service bulletin) warn; the tabs are hardened steel and rebending tends to crack them at the bend, a problem that's likely to show up at the worst time.
Madison? we must know each other.
 
@grizld1 (and Yamaha in a service bulletin) warn; the tabs are hardened steel and rebending tends to crack them at the bend, a problem that's likely to show up at the worst time.
Madison? we must know each other.
I was told you are supposed to heat it up, considering I bent them about 1mm I not that worried about it.

We do, the head on this engine actually came from you. Chuck grabbed it for me this fall.
 
Yesterday, I spent a little time turning an alloy rod for the rearset shifter linkage. Took a lot longer than it should, since I started with a 20 mm piece. Final diameter 11 mm, tapered to 9 at the ends. M6 RH and LH female threads, respectively.
 
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I knew this might happen. Those 1970something tires were not going to let me flex them off with irons and rim protectors. Too risky. My cable cutter popped one bead. So, in the AM I will get a cutting disc out,cut to the other bead, pop it, peal it off. Tires are the worst...even skinny bicycle tires have grunting on occasion.:cussing::banghead:
 
Tire trick I’ve used very successfully is just cutting out the sidewalls with a box cutter. Just cut the sidewalls all the way around to make two “donuts”. Much easier to get them off that way versus trying to ply the whole rigid ancient rubber off in one piece.
 
Fully compressed spring.JPG no compression.JPG Humm, back to where I was mid summer, counting my 447 cam chain links after I split the chain unfortunately. I did't think to get the bearings out then camshaft out...that chain was still tight in there. I'm counting 106 including the link I took out. Going to order a new continuous 106/447 cam chain. Using the original 256 tensioner. As much as I played with that 256 pitch sprocket wheel before removing chain n cam, I could not see that chai hitting more than 3 teeth at one time up to really just smashing the wheel into the chain. Over 3 teeth at a time...pitch problem and I would need to hunt down a later non-sproket tensioner that fits my 256 mount hole pattern. could not find one back then. OK, a quick visit to the garage and put the cutting wheel to my tires.
 
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Tires off. Uses the hand saw I cut tree limbs with, then lifted the beads a bit to get the cutter jaws in. No dates on tires or tubes. Going to mate up my engine covers and tape them and mask the piston-less top off so I can prime and silver paint to top or the engine case....waiting on a cam chain. Those cases are going to need some time with 400 grit, etc. to get out some embedded stains. But top of case clean and ready to paint starting now. Bought a bunch of parts today.
*** Anyone notice this "yamahaxs650.com" website....just saw it now. Odd.
 
Humm, took my '72 starter out while deciding to paint below the front case split...for that matter, below the rear split as well. Starter spins like a Hurricane @ 11.8 v off my car. Seals look good, nobody's turned those long bolts (i couldn't with a JIS driver and don't have a JIS bit). See how I feel today priming that area or not. May not take the starter apart. I have a rubber seal for the gear end of starter. Using VHT primer.
 
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