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

[MCRider]

Mystic is correct, there is a need for the plate to be narrow enough for the tensioner to clear it in its fully extended positon. Mine is OK, purely by a serendipitous sloppy cut. Could stand a touch on the bench grinder.

The chains would have to be really worn out and in a slap happy condition for the tensioner to get to that point, but we must be prepared.

[Terry in Australia]

Thanks guys, that explains a lot, I'll go make on of them while it's fresh in my head. I sent my gears off to be undercut yesterday, and when they come back, they're going for Cryogenic treatment. The guy at the cryo facility said they do chains with excellent results as well, so I'll get my primarys and cam chain treated too. Cheers, Terry.

[mick7504]

Back in the 70's, we use to braze a small block onto the tensioner base for the spring foot to contact.
It worked well and same effect as the spacer plate.
Mick

[MCRider]

Back in the 70's, we use to braze a small block onto the tensioner base for the spring foot to contact.
It worked well and same effect as the spacer plate.
Mick

Wow, that's nice to know, I'd never heard of doing it at all till i saw Rob at Voxonda.com's idea of the shim plate. Or at least that's where I got the idea. Did you notice any increase in fatigue of the spring or was that not a concern?

(Plug to general readership: give Voxonda.com a go for some trick handmade parts.)

[MCRider]

Thanks guys, that explains a lot, I'll go make on of them while it's fresh in my head. I sent my gears off to be undercut yesterday, and when they come back, they're going for Cryogenic treatment. The guy at the cryo facility said they do chains with excellent results as well, so I'll get my primarys and cam chain treated too. Cheers, Terry.

That's good to hear about the chains. While I have no reason to doubt my Cryo tech, its always nice to get third party confirm. I was a little dubious about the chains, but figured it couldn't hurt and he was taking an awful liability risk for not too much compensation if he was zoomin me.

[voxonda]

Back in the 70's, we use to braze a small block onto the tensioner base for the spring foot to contact.
It worked well and same effect as the spacer plate.
Mick

Wow, that's nice to know, I'd never heard of doing it at all till i saw Rob at Voxonda.com's idea of the shim plate. Or at least that's where I got the idea. Did you notice any increase in fatigue of the spring or was that not a concern?

(Plug to general readership: give Voxonda.com a go for some trick handmade parts.)

Thanx for your kind words, Ron.

There are more ways to get the same result. I did it back then when I had no welding equipment on hand and came up with this 'shim-idea'. Never experienced problems with fatique of the spring. Think it's silicone spring steel.

Cheers mate,

Rob

[mystic_1]

Mystic is correct, there is a need for the plate to be narrow enough for the tensioner to clear it in its fully extended positon. Mine is OK, purely by a serendipitous sloppy cut. Could stand a touch on the bench grinder.

The chains would have to be really worn out and in a slap happy condition for the tensioner to get to that point, but we must be prepared.

Yup to all of the above, I wouldn't have needed to narrow the tail of mine if I'd made it shorter, but I wanted the plate to stick out a bit past the end of the spring's "foot" because I didn't like the spring sitting right on the edge of the plate. 

I think, but am not sure, that the tensioner will go to full compression on deceleration when the chain slack moves to the top of the run and the bottom run is taut.

mystic_1

[MCRider]

Mystic is correct, there is a need for the plate to be narrow enough for the tensioner to clear it in its fully extended positon. Mine is OK, purely by a serendipitous sloppy cut. Could stand a touch on the bench grinder.

The chains would have to be really worn out and in a slap happy condition for the tensioner to get to that point, but we must be prepared.

Yup to all of the above, I wouldn't have needed to narrow the tail of mine if I'd made it shorter, but I wanted the plate to stick out a bit past the end of the spring's "foot" because I didn't like the spring sitting right on the edge of the plate.  

EDIT: I had to think about that for a while. You're right the chains will be into the spring the most when they are straight, taut across the bottom. I was thinking wrong.

[mick7504]

Back in the 70's, we use to braze a small block onto the tensioner base for the spring foot to contact.
It worked well and same effect as the spacer plate.
Mick

Wow, that's nice to know, I'd never heard of doing it at all till i saw Rob at Voxonda.com's idea of the shim plate. Or at least that's where I got the idea. Did you notice any increase in fatigue of the spring or was that not a concern?

(Plug to general readership: give Voxonda.com a go for some trick handmade parts.)

Thanx for your kind words, Ron.

There are more ways to get the same result. I did it back then when I had no welding equipment on hand and came up with this 'shim-idea'. Never experienced problems with fatique of the spring. Think it's silicone spring steel.

Cheers mate,

Rob

From memory, I think that we use to tension them right up with a 3/16" or 1/4" block and as Rob mentioned, never a known problem.
Every set of cases that we split had this done.
A friend who was a Honda motorcycle mechanic back in the day showed me this modification but I don't know where the idea originated from.
It certainly worked ok.
Ron, fantastic work sir. Lookin' real good.
Mick

[voxonda]

Hey Mick,

Neither do I. In fact I heard a guy talking about more tension on the primaries, so I figured this out. But in fact it is a matter of just use your common sense. Once had a chance to see the inside of a factory endurance engine, think it was back in '74 or '75, and from my memory think it had another tensioner all together.

Rob

[mystic_1]

So before and after I installed my tensioner shim, I took a small digital scale and used the weigh platform to compress the primary tensioner.

The stock tensioner peaked at about 700g of force before bottoming out.

With the shim installed, the scale maxed out at 1000g of force, well before the tensioner bottomed out.  I estimate the force was around 1100g to 1200g of force at full deflection of the tensioner.

Just some food for thought.

mystic_1

[MCRider]

Whew, a hit or miss day, but a day it was.
First, install the main bearing studs. Instructions from DynoMan: install so at least 4.9in on the longs, or 4.0in for the short ones. Allowing 1+mm exposed after threading on the nut supplied and using the OEM washers. We dry fitted first, then as recommended used double nuts supplied, and 242 Blue Loctite recommended to thread them in to proper exposed length. Pretty much bottomed out the short ones, the 2 long ones were shy of bottoming out.


Then went on shop wide search for the half moon retainers of the transmission bearings. I swear they were just here. I was holding them out knowing I would need them. Looked everywhere, took at least 1/2 hour. Found them in a drawer of hardware above the workbench. So then... thre were 3 thrust washers for the transmission we couldn't find. They were right there, on the corner of the workbench... for months, never moved them. Now gone. Another search is on, at least 1/2 hour looking. Finally, I just said they were there, we moved everythingfrom there to the breakdown table...or the dunk tank. Looked in the dunk tank with no hope of finding them and ...there they were! Damn.

So some minor transmission assembly occurred. Then we put in the KS shaft. But not till after this.

http://forums.sohc4.net/index.php?topic=76789.0

Thx Brantley, nokrome, and Mystic.

I did it this way. Grab the end of the shaft with vice grips, screwdriver on the end of the spring.
Then turn the shaft with the vice grips in the direction as kicking the KS. The pin pawl rotates under its holdown.
.
Then use the screwdriver to lift the spring onto its seat.

Mystics procedure may work a little better.
Another set back. Pulling parts out of the "Cryo box". The primary chains wree seized up HARD in many places.

I'd cleaned them real good to have them magnafluxed, then cryo'd. When I got them back I should have soaked them in oil. Instead I left them dry and they rusted up. It may have been natures way of telling me not to use stock chains, so I ordered a set of the HD chains from Ted and Thomas of Classiccyclecity.  It will be a while to get them, but I've got plenty to do.

Scrubbed clean each disc of the clutch set. Its an 8 plate clutch from Phaedrus I, Barnett probably, but I've lost track. It was working fine when I parked the bike, hope it will work fine again. If not, it can be changed from the outside.

[KB02]

 

It was working fine when I parked the bike...

How many PO's have said that? 

Good looking progress.

[MCRider]

It was working fine when I parked the bike...

How many PO's have said that? 

Good looking progress.

Yeah, in this case, I am my own PO! Yikes!

Thanks.

[MCRider]

Not happy this week, roadblocks. No pictures worth sharing, I'm pouting.

 But we put our time in. First during the week, I scored a stator. Found an "excellent condition" example on eBay for $51 incl S&H. Bot it and it truly is in excellent shape, got it Friday. Other than some discoloration of the connectors, no visible evidence its ever been run. So that question is answered. Could have gotten by with the tired old one, "it was working when i parked it". But on a whim I went to eBay and scored. A rebuilt one from Rick's Motorsports Electrics is $189.

Futzing around with the transmission, its ready for final install. Undercut, Cryotreated, new bearings, etc. But ... We got stalled on an "extra parts" issue. Thrust washers. Finally determined they were from the parts bike transmission and we had installed all necessary for Phaedrus 2.

Then I could've thought for sure I'd sent the low mileage primary drive shaft to the Cryo people. But i can't find it anywhere. Maybe not. I have one shaft, but I should have 2. Maybe they still have it in a lost and found box, I'll call Monday. If not, I'll get them 1 or 2 or 3. a little more delay. I can send them a few other parts that have been missed as well.  But I'm waiting on my primary chains anyway.

Maybe I'll box up a bunch of stuff and send it to Brown's for polish and chrome. Its only time...and money.  

Anyway, a nice ride planned for the 25th for any Hoosiers within shouting distance. Check the Events forum.

http://forums.sohc4.net/index.php?topic=76505.0

[CBJoe]

Hey Ron,

The wife and I are going to try and join you...... Sounds like a good trip.  I should know for sure by Friday.  I've got to fly to Des Moines, IA for work on Wed and if it doesn't hold me over too long I should be good.

Gonna have to put the ugly King Queen seat on the Bonneville though!  Cant do 200+ on the stock BRICK.

later, Joe

[MCRider]

Hey Ron,

The wife and I are going to try and join you...... Sounds like a good trip.  I should know for sure by Friday.  I've got to fly to Des Moines, IA for work on Wed and if it doesn't hold me over too long I should be good.

Gonna have to put the ugly King Queen seat on the Bonneville though!  Cant do 200+ on the stock BRICK.

later, Joe

That'd be great.

[MCRider]

So after yesterday's very incredible ride... http://forums.sohc4.net/index.php?topic=76505.0  
Don't miss the pictures on page 2... we got back to work on the bike. So i bot a (supposedly) 73 primary shaft from eBay. Having unpacked it today, it is...NOT HOLLOW! WTF! I've never seen one like that, no chain oiler. Searching the Motogrid Parts fishies, it seems the very late Ks and the early Fs had 530 chains, space for the double row bearing, and no oiler. Anyone see any reason I can't use it? I don't want the oiler anyway.
here's a shot of my inventory: l to r: 2 shafts from parts bikes, single row bearing, and chain oiler, 3rd from l; is what was in Phaedrus K2; space for the double row bearing, and a chain oiler. (But this was in a K2 which should only take the single row bearing. I must have switched it out at some time, in favor of the double row); and #4 that i just bot: space for the double row and NO chain oiler, shaft is solid.


I did figure out where the thrust washers went, last weeks problems.
Ted from ClassicCycleCity said my primary chains are in, so gotta pay for them and get them here.

We stripped all the primary shafts I had. Since they are single row bearing shafts, into the bin they go. Ordinarily I wouldn't pull on a gear like that, but no real way to grab it otherwise and the bearings came off easily.

We ground, filed, and sanded down the casting marks on the brake caliper mounts. Figure I'll send these and calipers to Brown's for polishing and other bits incl the sidestand and front fender for chrome. Any body got some parts they need chromed and want to piggyback on my order? browns' has a $250 minimum.

We did some other organizing, sizing up the brake lines, other stuff, so it felt like a good session. Hope to have a few nites this week to get the momentum going again.

[MCRider]

A good session. Update on chains: I forgot how to use Paypal for prompt payment and by the time I got a transfer cleared to pay for the chains, Ted had to leave town on a mission for a few weeks. Anyway he was good to be patient with me, so I'm happy to be patient with him. The chains are in, paid for, and delivery will be a week or so away. Then I'll drop them along with a few other parts off with the cryo guy.

In the meantime, we've been collecting every single misc part, pin, bracket, etc that can be plated or polished, replated or repolished. I expected to do this after the engine was on its way, but the order has been switched.


Since the engine got delayed, I popped for a 3M cam chain tensioner as well. Hoping to see that soon.

There's been some discussion about removing the taper seat inside of a caliper. I thought I'd give it a go. Combinig a few of the techniques discussed... I got a small diameter drywall screw and ran it into the seat from above.

Then chuck it up in a vice and get a tire iron under it...

Pry up...

And it came right out.

Nice to know I can do it. But my experience has been its not necessary. I had just shortened the banjo bolt with a hack saw and these always worked for me in the past.

Plenty to do this week, hope to make more headway.

[Terry in Australia]

Well done Ron, and to solve your "solid primary shaft" mystery, I'm pretty sure that the "K3" shaft is for a K0. I'll do a little more research, but needless to say, if it is, I want it! Cheers, Terry.

[MCRider]

Well done Ron, and to solve your "solid primary shaft" mystery, I'm pretty sure that the "K3" shaft is for a K0. I'll do a little more research, but needless to say, if it is, I want it! Cheers, Terry.

Being that the shaft is machined for a double row bearing, it has been confirmed as being for a later model K or F. So no stealing parts from me this week. 

[Terry in Australia]

Bugger!

[Ecosse]

ron, i know this is a bit off topic but while perusing images of my other passion (no, not that!) i found a four-wheeled kindred spirit. at least where the livery is concerned.

[MCRider]

Thanks, boy that's beautiful! Perfect colors for what i want. Even without the flake, I'd almost consider it without. I'd expect the numbers are gold leaf with engine turnings. Can't tell if the flames are but likely. The trim color between the gold and purple (magenta? not quite red or pink) ties it together.

[MCRider]

Updating early as I'm requesting comments. Got a little physically done, spent some money otherwise. HD primary chains are on the way, HD cam chain adjuster from M3 shipping wednesday. While disasembled calipers for finishing, I realized that I had nicked the chrome piston. Probably outside of the seal, but disturbing anyway. My guess is i tried to pry on them to get them out before i learned the tricks of compressed air and grease guns. So, since I'm waiting on other stuff, I ordered and received 2 phenolic pistons from forum member Kevin400F. Pictures:


So I've laid out a palette of parts to send to Brown's. After talking to them they charge the same for polishing as they do chroming, no discount. Bummed at first, but now I'm thinking would this stuff look good chromed? Brake calipers, mounts, carb tops and bottoms. The other stuff was getting chromed anyway.

Will raise the overall level of glitz, and be less maintenance.

Comments? I'm ready to ship Monday, gotta decide.