Top end rebuild

[doctorgonzo]

Ok, looks like I have located a head. He is supposed to call back shortly for a price for the whole shebang from the head up (cams, cam ends, cover, etc...). I don't have my shop manual with me which would probably shed some light on this, but... My philosophy is, while I have a head, off the bike, I should rebuild it (even if it may or may not need it) before I put it on. I have never been down that far in a bike engine (car once or twice) so looking for some insight. If you were doing it "right", not "no expense spared", but willing to spend some money, what would you do? Valve seats... new valves... measure the valves and only replace if too worn... take valves out and get the carbon off... new cam chain.... I want to put my parts list together as soon as I can so they and the head ship at roughly the same time.

 

[rapidray]

COMPLETE disassembly, hot tank of ALL parts, inspection of ALL parts, replace parts as neccessary. Check for play in the guides &, if neccessary, replace guides. Valve job, new seals, reassembly. Look closely at the seating surface on the valves for pitting or grooving. If there is any, replace the valves. Remember this, if you are looking for additional power, larger stainless valves are CHEAPER than STOCK valves! Ray.

 

[doctorgonzo]

COMPLETE disassembly, hot tank of ALL parts, inspection of ALL parts, replace parts as neccessary. Check for play in the guides &, if neccessary, replace guides. Valve job, new seals, reassembly. Look closely at the seating surface on the valves for pitting or grooving. If there is any, replace the valves. Remember this, if you are looking for additional power, larger stainless valves are CHEAPER than STOCK valves! Ray.

Thanks Ray, that's what I was looking for, and couldn't think of a better source. Know a good source for the stainless valves?

 

[Nessism]

The stock valves are likely to be more durable than stainless valves so I'd go that way if possible. At any rate, you most likely won't need valves but measure everything and compare to the service limits. When rebuilding my old 450 head I tore apart the ebay head I purchased and the old head from the bike and took the best parts based on the measurements. Clean up everything, lap the valves, and reinstalled the best parts along with new valve stem seals.

Good luck.

 

[Suzuki mad]

Clean it up. Inspect all parts, cam shafts, followers, buckets etc. Flip the head over, remove and clean valves, ports, new valve guide seals. Inspect valve guides and check valve springs for tension.
I'd go with stock valves. If the heads valves are OK 'lap' them in so they seat nice and install.

Suzuki mad

 

[doctorgonzo]

I'm suspecting that I'll have enough good valves. I don't have a shim below 2.50 on my current head (which is at 30K miles), so not overly worn I imagine, and surely at least several of the valves in the new head are in good shape. I'm doing this because my current head (explained in another thead) has not one but two extractors broken off in it, and 5 of the other exhaust header holes are already heli-coiled. Just wanted to make the new one pristine as possible and do any other head mods I would ever want to do while it's torn down. What's the opinion on porting the intakes? Only as good as the ability of the guy who does it?

 

[Nessism]

Wouldn't hurt to remove any casting flaws but I wouldn't attempt to change the port shape any.

 

[Suzuki mad]

Clean it up....remove and clean valves, ports.....

I run a 'wire' brush on a dremel in the ports to clear any carbon deposits thats all. No polishing or tuning work.

Suzuki mad

 

[doctorgonzo]

Thanks guys. Clean them up only. I have to admit being a bit scared, but I was scared of carbs 4 or 5 months ago too, and they turned out to be cake.

 

[hampshirehog]

Lovely little trick for when you're putting the new valve stem oil seals in place. Thread your oil seal on to a thin screwdriver and then poke the end of the screwdriver in to the top of the valve guide (holding the seal up near the driver handle). Let the seal drop in to position, give it a gentle push on and remove the screwdriver.

Yeah, I know it's bloody obvious but when I started on the spanners and 'knew it all' I used to fiddle about trying to get those seals on square with my fingers for ages, and fingers don't fit in there. And most embarassing of all was the fact that it took old John, a BSA mechanic to show me the trick - no oil seals on a Beezer.

 

[doctorgonzo]

Think I found a good deal. I got a call back, $289.00 for everything from the head gasket up, cams. cam ends, cover, etc.. all included. He said he was going to cut the cam chain instead of taking the cam ends off, figure he wants me to screw up the bolts if they are tough to get out. $23.00 shipping.

 

[heathen]

before you buy it call this guy . he wanted $150 for a complete head for my 750.

bates discount cycle
800-822-1465
972-495-5205

he is in tx and ships anywhere U.S.

 

[TheCafeKid]

Lovely little trick for when you're putting the new valve stem oil seals in place. Thread your oil seal on to a thin screwdriver and then poke the end of the screwdriver in to the top of the valve guide (holding the seal up near the driver handle). Let the seal drop in to position, give it a gentle push on and remove the screwdriver.

Yeah, I know it's bloody obvious but when I started on the spanners and 'knew it all' I used to fiddle about trying to get those seals on square with my fingers for ages, and fingers don't fit in there. And most embarassing of all was the fact that it took old John, a BSA mechanic to show me the trick - no oil seals on a Beezer.

Couple other lil tricks for the keepers: One, use a lil parts getter magnet, and some grease (with no Moly content preferably) as temporary glue on the keeper. Stick the keeper on the magnet, stick it in the window of your valve spring compressor tool, and with a dentists pick or scribe, push the half of the keeper on the valve stem and the "glue" will hold it there. Thats one way Steve found.

I found that if you lay the halves of the keepers on top of the valve spring facing the way you want them to go on, with the ends of the keepers in the groove between the stem and the spring, and GENTLY undo the compressor clamp, they will get trapped in the groove and stand up just the way you need them. Takes some practice, and some patience, but it works

 

[catbed]

you can pretty much count on Ray to sum it all up!

 

[doctorgonzo]

Couple other lil tricks for the keepers: One, use a lil parts getter magnet, and some grease (with no Moly content preferably) as temporary glue on the keeper. Stick the keeper on the magnet, stick it in the window of your valve spring compressor tool, and with a dentists pick or scribe, push the half of the keeper on the valve stem and the "glue" will hold it there. Thats one way Steve found.

I found that if you lay the halves of the keepers on top of the valve spring facing the way you want them to go on, with the ends of the keepers in the groove between the stem and the spring, and GENTLY undo the compressor clamp, they will get trapped in the groove and stand up just the way you need them. Takes some practice, and some patience, but it works

Oh don't worry, I am going be hitting you and everyone up for every trick you know before this is over. I did a car head about 20 years ago as a teenager, but this is my first time into the guts of a cycle engine. Got to be done though. The new exhaust is never gonna seal as is, plus something bad going on inside my current head because I am leaking oil from around one of the exhaust header bolts where there should be no oil.... it must me blowing past the valve.

 

[Suzuki mad]

Each of the valves sits in pockets which are filled with oil. (Thats another trick for when you rebuild the head!) Its possible that some PO has drilled and tapped too far into the casing causing it to leak. From the sounds of it this head had been in the wars.

Suzuki mad

 

[doctorgonzo]

Each of the valves sits in pockets which are filled with oil. (Thats another trick for when you rebuild the head!) Its possible that some PO has drilled and tapped too far into the casing causing it to leak. From the sounds of it this head had been in the wars.

Suzuki mad

You got it! That explains it. Yes, PO drilled too deep and when I ran a tap (didn't drill AT ALL only ran a tap down it) down the already heli-coiled hole I managed to hit that black gold... texas tea.... took the tap out and oil followed. I'm going to try teflon tape on the bolt and see if I can stop minimize that leak so it remains rideable while doing this head.

 

[doctorgonzo]

OH yeah.. odds this thread has about 1000 bumps coming over the next month or so.

Camchain:
With only 30K miles on my chain, odds are it's still within spec, I looked at the aftermarket ones on Z1 ($30) and the OEM ones ($70). My question is this. Would you install the my old OEM one I have on the new head if still within spec? How would I even do that? Pop a rivet and put one back in... use a "master link? I assume the aftermarket aren't as good. If I should go with a new one, use OEM?

 

[srsupertrap]

Ok, looks like I have located a head. He is supposed to call back shortly for a price for the whole shebang from the head up (cams, cam ends, cover, etc...). I don't have my shop manual with me which would probably shed some light on this, but... My philosophy is, while I have a head, off the bike, I should rebuild it (even if it may or may not need it) before I put it on. I have never been down that far in a bike engine (car once or twice) so looking for some insight. If you were doing it "right", not "no expense spared", but willing to spend some money, what would you do? Valve seats... new valves... measure the valves and only replace if too worn... take valves out and get the carbon off... new cam chain.... I want to put my parts list together as soon as I can so they and the head ship at roughly the same time.

Have your Machinist inspect every threaded insert in the head, paying close attention to the Cam Bearing Caps and valve cover bolt holes. These are all merely machined into the aluminum head and are prone to fail (pull out).

 

[doctorgonzo]

Have your Machinist inspect every threaded insert in the head, paying close attention to the Cam Bearing Caps and valve cover bolt holes. These are all merely machined into the aluminum head and are prone to fail (pull out).

Good one. Every bolt hole will be inspected, you can bet on that. I was going to have the ports maybe lightly worked to just smooth them out from the rough casting, (unless they want too much money in which case I will try and do it myself), so could have them checked then.