Topic: Phaedrus: CB750 RestoMod - Update: 09/23/21 w/ new video

[MCRider]

Terry........thanks for the tip

Ron....I'd expect to be locating a replacement cylinder-block. The pistons should accompany the block so the boring of each cylinder matches the piston.  When you get everything back for paint and assembly..........each piston should be marked for the hole to which it belongs. I'm sure Mike is on top of this and probably has spares in the attic

Your old block may just be waiting to be fitted for a 915cc kit.

The sleeves in my block, for the 888cc kit, (67mm) could be bored out to 915cc. (68mm) But I think I'd rather resleeve it and reuse the ARIAS 888cc pistons which are near new.  The cyl block is one of the few parts still original to the bike. But I have a spare and I'll do whatever is quickest and easiest. Incl a 915. 

BEsides I have some custom sidecover emblems that have "888" on them instead of "750", I'd lke to use.    

[MCRider]

Old Scrambler: as to piston placement. The ARIAS pistons were stamped from ARIAS with a 1 and a 3 on 2 of the pistons. A 2 and a 4 on the other 2.

Meaning it was a 50/50 guess.

But i agree with you they should have been hole specific and well marked. The machinist has since passed away and I don't like to speak ill of someone who can't defend themselves. He was referred to me by a respected CR750 builder who used him and Big Jay at APE had good things to say about him.

Maybe he had them marked iin a way I didn't recognize. In any event it appears all 4 holes are too big. Assuming this is true, and I had caught it way back when the deal was fresh, I'm sure he would have made it good.

For now I'm considering it a start from scratch. Except that the head was ported by the same machinist and I'm hoping that it was done well, as he had done on hundreds of other heads.

[CBJoe]

Sweet.... are you going to try and get Phaedrus running for the Mods vs Rockers down at Melody Inn this year? 

Cheers, Joe

Do you know the date yet? I googled it but no hits.

Sorry.... missed that question.  June 1!

http://www.rockersreunionindy.com/

Cheers, Joe

[MCRider]

Sweet.... are you going to try and get Phaedrus running for the Mods vs Rockers down at Melody Inn this year? 

Cheers, Joe

Do you know the date yet? I googled it but no hits.

Sorry.... missed that question.  June 1!

http://www.rockersreunionindy.com/

Cheers, Joe

It'll be close, but I'd like to get there.

[MCRider]

Update: After some tag with FED EX and UPS, the head and Cyls are in Mike's hands now. We had a panic in that after the parts were gone, we could only locate 3 of the 4 big knock pins. Fear was it had dropped into the bottom end. Hope WAC it was stuck in the head and shipped to Mike. Hope wins out this time as Mike reports its in head. YAY!

Prelim inspection indicates the cylinder deck may have been surfaced too far, allowing the head to sit lower in the stack and the valves to hit el pistones.

As to smoking, well there was a ton of oil in the ex ports, so yes it was smoking. While curious, I don't really care why, just want it fixed.

This weekend we hope to do the speedo test and ship the instruments out.

While the engine is denuded, I've been suspicious that the cyl studs are weird. The nuts just barely pulled down all the way, or not quite. I forget where I got them from. I'm going to pull one and compare it to the new APE studs i have.  I would prefer the stud have one thread showing at the top.

Anyone know or care about if the head nut washer is used. Putting the head nut flange right on the head?

[iron_worker]

I'm also curious to know wether the washer is needed since the flange nut has roughly the same contact area.

IW

[MCRider]

I'm also curious to know wether the washer is needed since the flange nut has roughly the same contact area.

IW

I've done some Google searches. Found some car stuff. The washer is hardened, and allows the nut to turn relatively unimpeded. PResumably to get good torque readings.

[Terry in Australia]

That's it Ron, the washer helps when you're torqueing the head down, and the two copper washers on the studs that go up through the oilways help keep it all oiltight.

The threaded portion of the studs should be longer at the case ends than the head ends, but if yours are aftermarket items, it could just be that they're not well designed and are a bit short.

You should only have a thread or two exposed above the nut and washer when you've torqued the head down, but they should all be "proud" of the nut. Cheers, Terry.

[MCRider]

That's it Ron, the washer helps when you're torqueing the head down, and the two copper washers on the studs that go up through the oilways help keep it all oiltight.

The threaded portion of the studs should be longer at the case ends than the head ends, but if yours are aftermarket items, it could just be that they're not well designed and are a bit short.

You should only have a thread or two exposed above the nut and washer when you've torqued the head down, but they should all be "proud" of the nut. Cheers, Terry.

Thanks Terry. I've never seen the 2 copper ones of which you speak. Later models?

While Googling the situation, I ran across the install instructions from APE. They indicated as you do, that the long threaded end goes in the case. I couldn't remember so that settles that.

ASsuming Mike is correct (he just made a quick glance at it.) and my cylinder was decked too low, that makes the stud problem even worse. The studs are no more than even with the top of the nuts. A few may be a half thread shy of level. Probably no real problem, but I don't like it and will try to rectumfy.


I got a full 20lbs of torque, but would prefer that the whole nut is pulling.

[Terry in Australia]

Yeah mate, I've used a NOS RC stud kit (with "waisted" studs for the two centre rear studs to allow for the oil up to the head, the same studs that the copper washers go on) and APE studs in my current bike with no issues.

I torque mine to 25 foot pounds in small increments, leave 'em overnight, loosen them and re-torque them again, and they don't leak. Ever. Cheers, Terry.

[MCRider]

Yeah mate, I've used a NOS RC stud kit (with "waisted" studs for the two centre rear studs to allow for the oil up to the head, the same studs that the copper washers go on) and APE studs in my current bike with no issues.

I torque mine to 25 foot pounds in small increments, leave 'em overnight, loosen them and re-torque them again, and they don't leak. Ever. Cheers, Terry.

I've been through the parts fishies from K1 to K6 and no copper washers. All were "thrust washer, Quan 16". Maybe an Oz thing?

Waisted eh? That would be cool. The ones in my engine are not waisted. I don't know the origin of what I have. I know I have another new unused set in a box. They are on a blistercard which should have a name on it. Hope they are APE and a tad longer.

I think the APE instructions said 22 to 25lbs. I figured for a mild engine 20 is 100%+ of the high end of the stock range, Has been sufficient so far. I think this time I'll tick it up a few. Think I'll treat myself to a new torque wrench.

Youre routine sounds intriguing, think I'll try that too.

[brandEn]

The 77-78 F motors have 4 copper sealing washers and dome nuts... maybe Terry is confusing the two?

[MRieck]

The 77-78 F motors have 4 copper sealing washers and dome nuts... maybe Terry is confusing the two?

I have advocated for a long time to use the copper washers under those 2 stud nuts. The best scenario is to use the 2 copper washers AND the factory acorn nuts from the F2. The is no possibility of a leak at that point. I came up with the idea as far as I know. Maybe I was beat out but buy whom I don't know.

[brandEn]

We need a "The Thoughts of MReick" thread. You have some great info to always share.


So use two 77-78 F copper sealing washers and dome nuts on the K top end oil feeds?

[MCRider]

We need a "The Thoughts of MReick" thread. You have some great info to always share.


So use two 77-78 F copper sealing washers and dome nuts on the K top end oil feeds?

Shhhh...don't bother him, he's working on my head.      

[brandEn]

Hey don't you bother him he's working on my head AND cylinders! haha

[MCRider]

Hey don't you bother him he's working on my head AND cylinders! haha

Well, he's got my cyls also.

My stuff's better than yours!   

[brandEn]

 

[MRieck]

Hey don't you bother him he's working on my head AND cylinders! haha

You cylinder is done and looks really nice. The head just needs the seats blended after boring them....I'll be doing that today. Bike is going to scoot nicely I'd say.

[MCRider]

Just got off the phone with Mike and we have a plan. New (to me) cyls with new OS sleeves. Bored honed surfaced. Paint.

Mill the piston heads to avoid contact with valves. Reduce some excess CR as well.  Pistons and rings are reusable.

My port job is good, but he'll touch it up and open up the chambers a squish, further decreasing excess (for my purposes) CR. I was pumping 240psi on all 4 cyls and that's more than I need.

so its on to parts and stuff. New SS valves with 1.5mm OS intakes. More HP! Bore the ports to match. Fresh valve job, guides, seals, etc.

Yahoo. I'm in the running for a $1/2 milion CB!

[Terry in Australia]

The 77-78 F motors have 4 copper sealing washers and dome nuts... maybe Terry is confusing the two?

I'm easily confused mate, but I've been using the copper washers on those studs since I rebuilt my first K1 engine in 1982, because the copper washers came in the gasket kit I bought, and I thought it'd be a good idea, at the time.

I haven't used the domed nuts as Mike has suggested, but I've had no issues with oil leaks either, especially with APE studs. The domed nuts are probably a good idea though, I might use some when I rebuild my engine later this year. Cheers, Terry.

[brandEn]

Good to know. I will be putting together my top end soon and will use them as well.

[MCRider]

Good to know. I will be putting together my top end soon and will use them as well.

Mike suggested to me using the 2 copper washers n the pressurized studs, with dome nuts.

[MCRider]

Predicted Sunday storms pushed up Shop Day to today, Sat. Clear and warm. We needed to roll Phaedrus outside 52 ft 3 times to collect the data needed to recalibrate the speedo.

We clipped a paperclip to the speedo cable. Made a mark on the housing. AS the cable turns you count the number of revolutions with a final partial. Ours was 23.90 turns. After 3 tries, all the same.


Ready to pack and ship.

Suspicious of the length of my HD cylinder studs... not sure where I got them. Dug out my second set, definitely APE. The APEs are about 1 to 2 threads longer. Additionally, the threaded amount of the end that goes in the cases is less. Result is about 2-3 threads longer above the head. So we'll be swapping out studs tomorrow, while it rains outdoors.

Note proper stud removal tool. Craftsman, not APE, but similar design.

[MRieck]

Just got off the phone with Mike and we have a plan. New (to me) cyls with new OS sleeves. Bored honed surfaced. Paint.

Mill the piston heads to avoid contact with valves. Reduce some excess CR as well.  Pistons and rings are reusable.

My port job is good, but he'll touch it up and open up the chambers a squish, further decreasing excess (for my purposes) CR. I was pumping 240psi on all 4 cyls and that's more than I need.

so its on to parts and stuff. New SS valves with 1.5mm OS intakes. More HP! Bore the ports to match. Fresh valve job, guides, seals, etc.

Yahoo. I'm in the running for a $1/2 milion CB!

Ron...great speaking with you yesterday. A gentleman and willing to spend what it takes to get it right. The top end will be perfect and match the rest of the build.