xs750 build step by tedious step, "build-along" with me

ok I have half of the questions answered., I started the day off figuring out how to measure the bottom of the dog hole on the factory gear, I ground down the tips of a protractor until I could fit it in the hole and adjust it for the width of the hole, in doing so I found out that indead the factory fifth gear does have a taper that matches the dog on the slider gear next to it, you can see with the naked eye the taper on the factory dog, not so easy to see it on the dog hole, OK, so at this point I have COnFiRmerd for sure the factory holes are larger the deeper you go, I needed to know for myself before any furter speculation drove me crazy.... so at this point I use the same protractor toi measure the holes in the mikes gear, and I ws disapointed to find thath the mikes gear was the same size hole all the way down, hmmmm i said that would produce the problem that was posted in this link
http://www.xs650.de/forum/viewtopic.php?f=1&t=28908&p=275861&hilit=5.+Gang+rad#p275861

hmmm so how are so many people having succsess with mikes gear , with or without the se3cond mikes gear, so as im sipping my coffie , i decide to use my calipers and the very presise edges of the internal measuring tips, just kinda farting around at this point, and I knoticed something, thes fit up tight against the two walls of the mikes gear nice and flat, again shgowing me that the hole was the same sise all the way down, but what I knowticed is that the gear kept shifting croked in my hand, and I would fiddle with it thinking I didnt have the caliperrs seated proper, and after a few tries I realized what the heck was going on..... any guesses ... thats right boys and girls, to make the machining process simpler (and cheaper) the dog holes in the mikes gears are cut at and angle, so that when the transmision s under load the dogs ARE fitting into a "tapered hole" BUT and a BIG BUT in doing so when you are on de-cellaration the taper is not there for the dog, and the gearbox is then relying on the shift fork to keep in in gear... ya see to machine that hole with a taper on each side of it, is a two maybe three procecces to get the taper like factory....... but if they just cut the hole with the entire hole at and angle, then there is the proper engagment under load, (on the gas in 5th) thats when it would want to pop out of gear the most, ...and I can only asume they didnt concern themselfs with it poping out of gear on the decel..... very very interesting and I feel victorious in finding half the 2 questions answered, here is some photos, I did also notice there is a very very clean surface inside the dog holes on MY mikes 5th overdrive, nothing like the undercut stuff i was shown a few posts ago.. I tried to take some good close ups, as a mater of fact I dont know if the gears from mikes are tumbled or shot peened or what after they are made, because there are no machining marks on it anywhere, it actually doesnt even look like it was machined at all, in fact if anyone is familiar with cast powdered metal gears, it looks to be manufactered like that, most gears in you ryobi or milwakie tools are made this way, but I wouldnt have thought that process was strong enuf for this aplication. ok on to the photos.
 
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Yes, auto/bike gears nowadays are made using the MIM (Metal Injection Molding) process.

Seen a lot of vids on Electrical Discharge Machine or Machining (EDM).
Could be a solution. You'd have to make a precision fixture...
 
hmmm twomanyxs1, i wonder why they only gave the gear the angled dog holes if they where MIM ing the gears, maybe because they cant make a hole with a bottom bigger than the top with that process, so they figured they would give the "drive side" what it needed, and that would be good enuf
 
sorry the build hasnt moved forward for a couple days, I had a problem with my work truck,,,, does this pinion look ok to you guys, its still good right??just some Jb weld and it will be all good I hope
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Just curious if you ever got the kedo adjusters? It seems they never cancelled my order and I should have a set of four coming soon. Let me know if your interested in them. I will probably just run the porsche adjusters since I put in the time and effort cutting them down.
 
been trying to get the bottom two exhaust studs out of the head so I can surface it, I got one out with the dubble nuts locked together, but the other one is stuck stuck stuck, I put pb blaster on it overnight, I got the head hot with a tourch, thinking the aluminum would expand more than the steel studd, still stuck,

Sugestions???:umm:
 
been trying to get the bottom two exhaust studs out of the head so I can surface it, I got one out with the dubble nuts locked together, but the other one is stuck stuck stuck, I put pb blaster on it overnight, I got the head hot with a tourch, thinking the aluminum would expand more than the steel studd, still stuck,

Sugestions???:umm:
I TIG a nut on the stud and crank it out with a wrench. 'Course... you'll need a new stud....
 
im getting ready to begin asembling the engine, I had asked if anyone knew what the RA was suposed to be for the head gasket surfaces,, IE the top of the cly and the bottom of the head, and with some reserch it seams its suposed to be RA50, and since I dont have a million dollar spectrometer to find out what my RA is, I have found a wonderfull chart, this chart shows you aproxamatly what RA you will end up with using diferent grit paper. im not sure the pdf made it to the posting, let me know guys, looks to me like if you want a RA of 50 you would want to use 120 wet dry, hmmm that seems a little ruff to me, I will be surfacing the cyl and the head in the milling machine today then flat sanding on a piece of glass with 600 grit, well I was going to use 600, now im confuseled
 

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Dang you might end up beating me putting my engine back together and I didn't even split the case. I didn't sand on my head surface as I was able to remove all the old gasket and residue with good ole elbow grease.
 
i don't have old gasket material, I want to have a perfectly flat surface, I checked them with a strait edge and they where darn tootin flat, but I just want to take the step that you would if it wasn't flat... ya Know "tedious step by tedious step" :rolleyes:

and also maybe subconsciously to raise the compression .01 lol
 
get some mapp gas and heat the exhaust stud surrounding area,they come right out not destroying the threads
 
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