Pabeye
Older than Dirt
Thanks ippytattoo she is a rescue dog, and my second Bull Mastiff. She was abused by her PO. I've had her about a year...she is wonderful!
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79 xs650 Special - No Spark... But 12v. help?
- Thread starter dhx78
- Start date
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- Tags
- electrical engine
Pabeye
Older than Dirt
Still to chicken to tackle the engine....having fun taking stuff off though.....lets see how much I can LEAVE off of the rebuild! I want her lean and mean! Stick an engine in there and I will have more or less what I'm looking for! LOL.....Do ya like the handle bars??....LOL, LOL
And to think this started as a question about ignition. Well, you're doin' it right. These old bikes really do need to be completely gone thru.
Reminds me of my old vega. Went to fix a small water leak at the base of the windshield, and before I could stop myself, pulled the interior, all the glass, engine/trans, took it all the way down to bare metal, ...etc. Afternoon project morphed into 10 month build...
Reminds me of my old vega. Went to fix a small water leak at the base of the windshield, and before I could stop myself, pulled the interior, all the glass, engine/trans, took it all the way down to bare metal, ...etc. Afternoon project morphed into 10 month build...
Pabeye
Older than Dirt
Well I gathered up all my courage, and against my BETTER judgement......started to disassemble the engine today. FIRST I had to hump that mother down the stairs to the basement where I have amenities like a music system, heat and good lighting. ( not to mention I'm closer to the fridge ) I managed that with out pulling my back out (thankfully) and then I built a primitive frame out of 2X4's so the motor would sit up straight. With the help of my online friends ( you guys! ), some on line tutorials and a nice hard copy of the shop manual that a friend sent me.....I got this far. I'm quittin' for the night. Can't figure out how to loosen the cam chain - which I am NOT going to cut, so I can pull off the cam shaft and get to the cool stuff under neath it. Gotta watch that video again!
Pabeye
Older than Dirt
First let me that everyone on the board who has helped me out with this project. I oculd not do it with out you guys! Here is today's update:
AHHH HAAAA! DE HOLE!!!
The con rod is stamped 447.........original pistons I guess.
Can't figure out how to get those pistons off. How the heck do ya compress that little ring that holds them in place?
NEXT Question....what comes next? Do I pull the valves or just clean 'em up? HOW do ya clean em up? Scotchbright? Wire brush? If I have to take it apart do I NEED a spring compressor or is there a make shift way of compressing the springs?
How do I tell if I need to do something with the inside of the cylinders? What is an "acceptable" amount of scratching if there is such a thing? Can I use a fine Scotchbright in there?
Can I put the parts into water with soap or Fantastic to clean em up? Kerosene dip maybe?
Here's what the bottom of the valves look like........any comments?
and so on and so on.......Thanks in advance.
AHHH HAAAA! DE HOLE!!!
The con rod is stamped 447.........original pistons I guess.
Can't figure out how to get those pistons off. How the heck do ya compress that little ring that holds them in place?
NEXT Question....what comes next? Do I pull the valves or just clean 'em up? HOW do ya clean em up? Scotchbright? Wire brush? If I have to take it apart do I NEED a spring compressor or is there a make shift way of compressing the springs?
How do I tell if I need to do something with the inside of the cylinders? What is an "acceptable" amount of scratching if there is such a thing? Can I use a fine Scotchbright in there?
Can I put the parts into water with soap or Fantastic to clean em up? Kerosene dip maybe?
Here's what the bottom of the valves look like........any comments?
and so on and so on.......Thanks in advance.
Pabeye
Older than Dirt
1) found a cool video on testing for valve leaks...pour a bit of acetone into the valve opening and see if it leaks out. I have on leaker on the intake side.
2) I finally got those little retaining rings off....a 50 year old pocket knife did the trick.........(Old school) LOL
Ahhh, now have to clean up all those parts and think about ordering new stuff!
2) I finally got those little retaining rings off....a 50 year old pocket knife did the trick.........(Old school) LOL
Ahhh, now have to clean up all those parts and think about ordering new stuff!
NONclow
Confirmed Laquer Breather
I feel for ya.... that's waaaay too long to work on a Vega.... not to mention ten more months worth!
laughing
I feel for ya.... that's waaaay too long to work on a Vega.... not to mention ten more months worth!
Hahaha, yeah, that was exactly the reaction I was shooting for! I've had so much stuff stolen over the years, so I thought "Who in their right mind would want to steal a vega?" Didn't quite work out that way, there were three serious attempts to steal it...
Pabeye
Older than Dirt
I learned this trick from an online video, or was it one of you guys? Who remembers? I'm OLD!. The compression tool sells for about $60........the big "C" clamp cost $15 I went whole hog and bout it at HD instead of Harbor Freight!...LOL......I HOPE it works as well when it come time to re assemble.
The only thing I changed from what was in the video was I switched from an old socket on top of the valve spring to PVC pipe..a lot easier to cut!
The only thing I changed from what was in the video was I switched from an old socket on top of the valve spring to PVC pipe..a lot easier to cut!
NONclow
Confirmed Laquer Breather
Good idea, but PVC has been known to shatter. I would also clamp the head in the vise before I supported the weight of the head through that clamp/tool/valve/spring/...head being clamped . I use a 1/2" pipe coupling like this one with chunk removed by two parallel cuts end to end (clamped in vise, hacksaw made short work), plenty of access (with hammer and punch if need be...)..... wear eye protection...
. I use a 1/2" pipe coupling like this one with chunk removed by two parallel cuts end to end (clamped in vise, hacksaw made short work), plenty of access (with hammer and punch if need be...)..... wear eye protection...Attachments
Pabeye
Older than Dirt
Thanks for the advice NON.........I did not consider the possibility of "shattering" PVC. will try and figure a way to support the head when it's time to install the valves.
Pabeye
Older than Dirt
I took the jugs (GAWD FORGIVE ME.......) to a HARLEY shop here in town. It is a well respected shop. He is gonna "mic" the bores and if all looks OK, he will hone them.......all for $40........not bad thought I. He did not think they needed to be rebored. In any case, that would cost $100 per hole.....and I figure I could buy a new one for not much more or even find a good used one on ole ebay. I'm hoping that the honing will do the trick.
I just placed my first order to Mikes.......bunch of stuff from float bowl plugs, to spark plug wires, gaskets for the head nuts, etc etc......not ordering pistons till the jugs come back from the shop and I get the report from the machinist.
I just placed my first order to Mikes.......bunch of stuff from float bowl plugs, to spark plug wires, gaskets for the head nuts, etc etc......not ordering pistons till the jugs come back from the shop and I get the report from the machinist.
NONclow
Confirmed Laquer Breather
Get the pistons FIRST! If they hone it, how much are they going to remove, .002", if pitted likely more. After the bores are measured, you'll know how much material will have to be removed to clean them up, then before they start honing measure the pistons (which can vary sometimes as much as .0008"!) to get the exact size of each, and the bores can be matched to the pistons. If honed first, the bores could be half way between the available piston sizes, or one will fit great and the other will either be too tight, or too loose . Then all that work will have to be done again! 
Good luck. Measure twice, cut once! 
. Then all that work will have to be done again! Good luck. Measure twice, cut once!
Pabeye
Older than Dirt
It may be too late as I dropped off the jugs a few days ago BUT if the hone was not done yet I'll tell him to wait......BUT......Question.........HOW do I know which size pistons to buy???.........
Any knowledgeble engine machine shop will not machine cylinders unless they have the pistons in their hands.
"HOW do I know which size pistons to buy???"
Go to www.biker.net and read the Yamaha Service Manual. You need to educate yourself so you understand the specs for piston/cylinder relationship.
NONclow
Confirmed Laquer Breather
Pabeye
Older than Dirt
I "rescued" the jugs from the Harley guy..untouched..........now will figure out the piston thing and then return them to the Harley guy for honing.........HOPEFULLY.......
Pabeye
Older than Dirt
Read the manual, still don't understand....when measurements get less than 1/16th of an inch...I don't understand!
Read the manual, still don't understand....when measurements get less than 1/16th of an inch...I don't understand!
I suggest you find a motorcycle shop that does cylinder reboring on Japanese engines (not Harley engines).
The cylinders you have must be measured with bore gauges for diameter, cylinder taper etc. A machinist that does this for a living can easily do that for you. Once the machinist knows the condition of the cylinders, and reads the Yamaha Service Manual, he can tell you if you need stock pistons, or first over size, or maybe 2 nd/3 rd over size.
Pabeye
Older than Dirt
Thanks for the advice RG........I'm not sure if the price to bore is the same in all the area shops, but the Harley guy wants $100 per hole to rebore the cylinder vs $40 to hone. Reboring is simply not an option for me.
I will take the measurements you described, ( or have some one do it...I have a friend who is a jet engine mechanic and he has volunteered to help with that.) then get the right pistons and hone. hopefully it will work out.
I will take the measurements you described, ( or have some one do it...I have a friend who is a jet engine mechanic and he has volunteered to help with that.) then get the right pistons and hone. hopefully it will work out.
