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Discussion Starter · #1 ·
So I am needing to find a machine shop for the servicing of my head and cylinders. After looking at both of them I believe baring any oddities found I should only need the head cleaned, lapped and oil seals installed. The cylinders are looking like thay are just going to need a cleaning and freshening. I just want to make sure that I pay a fair price. In fact I might even be up to shipping it somewhere if I know that they are good and fair. Also I get nervouse since there are really no machine shops that do a lot of bikes much less ones with a torsion valve setup. So if I take it to one of these shops should I remove the torsion bars and just take the valves and head or take the whole thing? As always thanks.
 

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owdskl said:
So I am needing to find a machine shop for the servicing of my head and cylinders. After looking at both of them I believe baring any oddities found I should only need the head cleaned, lapped and oil seals installed. The cylinders are looking like thay are just going to need a cleaning and freshening. I just want to make sure that I pay a fair price. In fact I might even be up to shipping it somewhere if I know that they are good and fair. Also I get nervouse since there are really no machine shops that do a lot of bikes much less ones with a torsion valve setup. So if I take it to one of these shops should I remove the torsion bars and just take the valves and head or take the whole thing? As always thanks.
They'll need to put the torsion bars back in place to allow their vacuum tester to check for valve leakage.
So leave them in - they're pretty smart guys. My machinist figured them out without any help from me.
If they need, they can ask you to show them how.
After they mike your cylinders you'll know what you have to do with the cylinders/pistons.

My guy charges $35 per valve to cut new seats and lap them in - $15 per valve to lap only. He charges $40 per hole to bore. Those are pretty competitive prices.
 

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Discussion Starter · #3 ·
Should I have new seats cut or is that something that is only needed if the seats won't properly seal?
 

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owdskl said:
Should I have new seats cut or is that something that is only needed if the seats won't properly seal?
That's a call I leave to the machinist - I go with whatever he thinks is required.

It's nice to have someone you can trust.......
 

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Discussion Starter · #5 ·
Thats the problem. I don't have a trusted one. I called 3 places today and 2 couldn't work on it and the one that said he'd have to see it said to lap the valves, do the seals and clean the head Would be $175. Totally high I think.
 

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owdskl said:
Thats the problem. I don't have a trusted one. I called 3 places today and 2 couldn't work on it and the one that said he'd have to see it said to lap the valves, do the seals and clean the head Would be $175. Totally high I think.
A monkey could put in valve guide seals - they should do that for free, for cryin' out loud.
 

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tbpmusic said:
A monkey could put in valve guide seals - they should do that for free, for cryin' out loud.
Yup, I agree. Here is the sequence in pictures.

The seal on the left is the replacement for the two part seal on the right.



It's tough to see what this is but here is the valve in place with the seal placed over it. Not shown is some assembly lube on the stem of the valve (oil works fine too).



I use a socket (I don't recall what size) to push the seal onto the valve guide. You'll feel it "click" when it's in place. I like to have the valve in place since it acts as a guide while you push the seal into position so it doesn't get cocked in there.



Here is the installed seal.



I think I found installing the locking collar in place the hardest part since I have fat fingers and couldn't get the bolt started. It took a few tries but a little magnet inside a 10mm socket would probably work good too.



Here is what I use for assembly. Use it liberally.

 

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Discussion Starter · #8 ·
If the head didn't weigh as much as a small block I'd just ship it to someone but it would wind up costing as much in freight as the repair work. I still haven't found anyone to do the jugs yet either. I'm gonna call a couple of race shops today to see who they use.
 

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Discussion Starter · #9 ·
Found a wholesaler on accident by calling the local dealer. He does all of their work and specializes in racebikes. Doesn't do the serious cleaning but will cut the seats and valves, decorbonize the head, and hone the cylinder for $110 total. If the cylinder is needing more he can bore out or even resleeve if needed. Yee Haw. I will keep you posted on the work.
 

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owdskl said:
Found a wholesaler on accident by calling the local dealer. He does all of their work and specializes in racebikes. Doesn't do the serious cleaning but will cut the seats and valves, decorbonize the head, and hone the cylinder for $110 total. If the cylinder is needing more he can bore out or even resleeve if needed. Yee Haw. I will keep you posted on the work.

That's good - see if you can get the pieces media blasted before you take them for the valve work.
 

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Discussion Starter · #11 ·
Is it possible to get it blasted afterwards but before I reainstall everything? I have a logistical restraint in dropping it off with him. Also should it be soda blasted or some other sort of media?
 

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He will appreciate having clean parts to work on......It inspires better results if it looks like you care about the job.....
 

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Discussion Starter · #13 ·
I am with you on that. I would normally have the shop take care of that but he doesn't have the capabilities. I just mean that it won't hurt anything like the new valve seats.
 

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owdskl said:
I am with you on that. I would normally have the shop take care of that but he doesn't have the capabilities. I just mean that it won't hurt anything like the new valve seats.

If you take a blaster, even soda, after he's done his cutting or grinding then you'll probably want to re-lap the valves. On the other hand, as long as you taped up the seat area or protected it from the blast media you'll be ok.
 

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Discussion Starter · #16 ·
Took the head jugs and pistons and had them soda blasted. Damn they came out good. I'm going to give the guy the head etc next week. I will start a post of pics in the project log today.
 

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Discussion Starter · #17 ·
Cylinders. Do you guys just normally leave the aluminum the same color it comes back brom the blaster or put some sort of a coating on it to preserve it?

 

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Discussion Starter · #18 ·
Heres the head. I am sure that the machinist will be very happy!! Thanks guys.

 
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