engine

Hey all, first time posting to the forum - though I've been around on the 650garage and a few others. I'm not new to the xs, however. Mine (1982 Heritage Special) has been in a perpetual status as project / PITA for a few years now. Bought it straight out of a muddy ditch next to some guy's...

Hello all, As you can tell I'm new here, I signed up a couple weeks ago and have been soaking up as much information as I can. I recently picked up a 75 XS650 in pieces that the PO had been rebuilding. He said the bike had no compression when he bought it and he found the rings were stuck in...

Hey guys! I have a couple of symptoms telling me my engine is getting old and probably needs a rebuilt. First off when I first got the bike i did an oil change, and changed the sump filter and the filter in the side cover. I noticed there was a decent amount of metal shavings on the magnets on...

so far from my own research i have found some engines specs and 2 different posted compression ratios for the 1981 xs650. i would like to know all of the technical specs if possible. i have searched this forum and others and have come up inconclusive for data. These are what i have found: 75mm...

So i'm honestly not sure if this noise is new or maybe I just haven't noticed it before. Cam chain tensioner/valves done correctly about 500 miles ago nothing on the bike has changed. It isn't a distinct metal knocking nor a carb chirp but its something in between the two. I can only hear it...

Looking for a late engine for my 81 special. Would consider something from the US but guessing the shipping would make it a no no. Anything considered. Will travel anywhere in blighty for the right motor.

Went to adjust the valves the other day and when I went to loosen the lock nut on one of them it snapped right off with very little effort. Wow, good thing that didn't happen when I was riding! Has anybody else ever had this happen on anything? I did some searching on the web and found a few...

Edited for brevity: I tipped my bike over two days ago and since then it has been spewing white smoke and now oil from the exhaust. Prior to that it was running perfectly, no leaks, no smoke, nothing. Checked oil level after tipping and it had lost a bit, so I refilled. Guessing that oil went...

Hello forum, long time creeper, first time poster I need some haaalp! I'm a new rider and this is my first bike. It's needed some work but I've been happy to dig in and get to know the machine. The Bike: 1982 Heritage Special, stock pipes, jetting etc. xscharge PMA, pamco ignition...

Ok guys, Ive been going over this damn thing for a week now. HHB PMA, Pamco, kick only. Thought it was the coil, nope. new coil installed and still no dice. fresh build over the winter, new wiring, had it running. I was ripping around town a bit. came home, parked it. a few days later i...

My piston rings have 75 stamped on them as do the tops of the pistons. Correct me if I am wrong but the 75 on piston would to me indicate the size is 75mm and the 75 on the ring would be the same, or would it. As I have bought STD 75 piston rings from Japan ( part# 447-11610-00 ) and the end gap...

Have a look then tell me what year this head is from. http://www.ebay.com/itm/10135-1968-1985-Yamaha-XS650-Top-End-Cylinder-Head-with-Valves-and-Springs-/152123180602?hash=item236b3f863a:g:NM8AAOSwzJ5XWklK&vxp=mtr What were the tells for ya? It is a shame the sellers are splitting the...

I just finished a rebuild on a '74. Bought not running, no compression on RH cylinder. Pull motor, rebuild top end (long story in there, not pertinent to my 'issue'), reassemble. No major headaches during rebuild. As I had suspicions of 'stuff' in the base (none found), I split the cases and...

I've tried to sit my rocker cover on after new psitons etc, and it won't sit flush against cylinder face. After reading through related areas on here, I took it off and sat it on 100% flat plate glass - it appeared to sit flush which I trust means it's not warped. I've tried joggling it on all...

I've tried to sit my rocker cover on after new psitons etc, and it won't sit flush against cylinder face. After reading through related areas on here, I took it off and sat it on 100% flat plate glass - it appeared to sit flush which I trust means it's not warped. I've tried joggling it on all...

Due to some frame modifications planned during my restore projects, I want to get a set of bare cases for some mock up projects. I am doing a 1979 Special and need to know if a set from a 1981 will be the same. This is probably a dumb question but the more I check into these bikes, It seems that...

Hello, So, my '82 xs650 was having charging issues. I checked the stator brushes and they were considerably worn, so I replaced them. In doing so, I removed the left hand engine cover, although in hindsight, I know I really didn't have to. While I was taking things apart, I realized that my...

A couple of weeks ago I did the electric starter fix and had some issues getting the side cover back on. I'd inadvertently let the kickstarter slide out enough that it wasn't seated properly. I fixed it by putting the lever back on and rotating the assembly until it popped into place. I'm 90%...

Got my plates and registration yesterday went for the first real ride in the evening. Ride up and down the road a few times no problem, went around the block feeling good. Half way around the block I stop at the corner go to turn left and as soon as the clutch starts to grab bike dies instantly...

I am blocking off the petcock on one side. I have steel and could make a plate, but considering the amount of cutting/grinding and the fact that the old extra petcock is the same shape already and just sitting there - has me thinking ..... Has anyone chopped one up and used that as a basis...