Topic: Headline: Hondaman rebuilds his old friend - FOUND GOOD OIL!

[HondaMan]

OK: DON'T USE THE ACE HARDWARE TEST TUBE RUBBER STOPS for anti-ringing rubber plugs... 

The rubber appears to turn to stone after just a few trips to 350 degrees. Since the heads run at about 325 degrees near the exhaust 'flowers', they will surely disappear in a hurry on yours, too.

Just a thought - don't powdercoaters use silicone plugs to seal holes?  They obviously are good to go at higher temps, as they bake pc.  Might you get some from a local shop or find a pc supplier that would part with just a few.  OR, maybe a forum member who powdercoats could weigh in...

Good luck,
G

Excellent idea! I have to go to the seal shop this week, will see if they have any high-temp silicone plugs? Hmm...

[HondaMan]

Today's adventure: removing the guides the machinist just put in. Twice.

[RAFster122s]

A real chemist supply place would probably have better quality stopper if you want to pick up a few and try them if finding the silicon plugs doesn't pan out. Maybe a PM to Powderman is in order...

Sorry you are having to fix it yourself, at least you can rest easy knowing what is in it.

Do you have several rebuilds in queue or going on simultaneously?

David

[RAFster122s]

Do you have a couple cracked fins near #4? Ugh...

[edhaeuser]

Eastwood sells different size silicone plugs for powder coating.  I think that Caswell does also.

[Jerry E.]

Sorry to hear of your machinist troubles. He was slow last year when you had him do my head, but it turned out alright, in the end. I think I had to wait for his vacation, too, as I recall.

[HondaMan]

Do you have a couple cracked fins near #4? Ugh...

Not anymore! I had my welder, a guy who came here from Ukraine and REALLY knows how to weld, build some up for me (I've had him do 3 engines for me, now, nice job all). I polished them back down and wanted to go unpainted: the jury is still out on that decision because the new metal still looks quite a bit different from the old. I've tried a few things to tame it down, maybe I'll get it yet? It's real "white" compared to the other, more "experienced"-looking fins.

[HondaMan]

Eastwood sells different size silicone plugs for powder coating.  I think that Caswell does also.

Thanks, Ed: I'll go check them out, too.

[HondaMan]

Sorry to hear of your machinist troubles. He was slow last year when you had him do my head, but it turned out alright, in the end. I think I had to wait for his vacation, too, as I recall.

Come to think of it, it was almost exactly last year, wasn't it?
Yours was one of almost a dozen he has done for me and others around here in the last 2 years alone. Every one of those where I had him install new guides (either Kibblewhite, APE, or CycleX types) came out with the required clearances (0.0008" to .0012" intake, 0.0016-0.0024" exhaust).

How he could screw MINE up after all that just blows me away...especially the ones that were clear out to .0058" loose...I'm still mad...

[HondaMan]

A real chemist supply place would probably have better quality stopper if you want to pick up a few and try them if finding the silicon plugs doesn't pan out. Maybe a PM to Powderman is in order...

Sorry you are having to fix it yourself, at least you can rest easy knowing what is in it.

Do you have several rebuilds in queue or going on simultaneously?

David

I have 3 'active' engines I am prodding along. Mine is one of them. One is a [very] slow low-budget, whole-bike rebuild (750K5), one is a resto-mod K4-come-K1 lookalike. There's 7 engines around me: I have 3 that I am slowly building to either put into one of the titled frames I have, or sell to someone who can trade me a "core" for a closer serial # match to the frames in process. For example, I have a K3 with frame to match, but a K4 engine for a K2 frame and a whole K2 in 500 pieces. I think I also have 2/3 of a K7 engine that was sorta in a K5 frame (sprocket mismatch issues) which I hope to turn into a K6 engine in the end.

Then there's my lonely 350F....

[Gman]

I polished them back down and wanted to go unpainted: the jury is still out on that decision because the new metal still looks quite a bit different from the old. I've tried a few things to tame it down, maybe I'll get it yet? It's real "white" compared to the other, more "experienced"-looking fins.

I think you should still go unpainted.  I have marks, scars, etc. on my body and they tell a story.  (Nothing very interesting, mind you, but they mean something to me.)  If your bike is a survivor, which, of course, it is, you should fix the broken bits, but I wouldn't hide the work.  As it stands, if someone notices a different color metal on the fin repairs, then you get to tell the story of the mother of all crazy hailstorms and laud the work of a master welder - pretty good deal in my book.

Cheers,
G

[HondaMan]

I polished them back down and wanted to go unpainted: the jury is still out on that decision because the new metal still looks quite a bit different from the old. I've tried a few things to tame it down, maybe I'll get it yet? It's real "white" compared to the other, more "experienced"-looking fins.

I think you should still go unpainted.  I have marks, scars, etc. on my body and they tell a story.  (Nothing very interesting, mind you, but they mean something to me.)  If your bike is a survivor, which, of course, it is, you should fix the broken bits, but I wouldn't hide the work.  As it stands, if someone notices a different color metal on the fin repairs, then you get to tell the story of the mother of all crazy hailstorms and laud the work of a master welder - pretty good deal in my book.

Cheers,
G

Yeah, you've got a point! Those poor fins have been broken off so many times, too, in one (wreck, accident, or stupid behavioral moment) or another.

[HondaMan]

Movin' forward again...
I painted the bottom case today, polished a little of the side covers so they look a little newer. Flipped the engine back upright, got the pistons ready to install and...drat. My piston ring clamps are at work(!). So, I shined it up a little more, got it ready for the pistons tomorrow.

Hope the valve reamer and hone tools show up soon: I ordered the whole set from Goodson on July 15th, still don't have it. Got an 'invoice' from them yesterday, showing that I paid for it already. Duh... they sent me an e-mail last Monday that said it shipped, but in 5 days it didn't show up from MN? Strange...

Then I decided to go work on swingarms. Got lots of those to do!

[70CB750]

What tools did you get?  Neway seat cutters?

[HondaMan]

Woohoo! They came today!

I already have those Neway seat cutters, and their polishing stones (all very nice stuff, works real well for hand-work like mine, better if you have a driver). This batch is their guides hones (diamond and carbide) in all their sizes that fit these bikes.

Now I can't wiat to get the new guides and install them, so I can try this stuff out! 
The APE guides were sent Monday. I gotta get some more of the -310 exhaust guides, if I can find (and afford NOS) them in Stellite. Hard to find. In 1974 Honda changed the metal on the -310 guides to cast iron like their other guides, so the Stellite ones are really hard to come by today. I suppose I could live with the cast iron ones if I had to, but would rather not: the Stellite will outlive them 3-1 or more. I would really rather ride my old friend for the next 20 years than take it apart again. This has been a sad summer for me. 

[BPellerine]

must be hard to have your old friend on the table but you know it will be ok.bill

[HondaMan]

Maybe I should retitle this thread, "How to fix it after your machine shop worked it over"...

I got the new APE guides, which APE makes as direct replacements for these heads, pre-sized perfectly.
But...
My head's holes have been quite widened by the shop installing 2 sets of guides into both sides of the heads, and those guides also being extracted twice. So, the perfect-fit APE guides fall right into the holes, loose.

So, plan C.
The bronze guides from CycleX are not as nice as APE's guides, nor are they as long (about 3mm shorter), but they are oversized on the OD by .0015" more than stock or APE guides (which are made .0005" oversize for a good press fit). Also, the CycleX ID is only 0.2585", so they will fit the F2/3 valves, too. This leaves more room for reaming them to fit, and their OD will let me press-fit them into my head. Sort of:...the last sets of guides that went in were these CycleX guides, and they were oversized by .0025", too: I didn't notice that at the time, and the machine shop didn't check in his hurry.

So tonight, I turned down the new CycleX guides to be .0020" oversize instead of their otherwise too-tight fit. I suspect that this very tight press fit (for bronze) caused the last guides to ripple and warp, and the shop's old, dull reamers then wandered during the fight through them, as he told me he ran the .260" reamer and thought the chips looked "kind of big" coming out: yeah, that would cause this problem on the bronze ones, all right (but twice? And also on the Honda Stellite guides? TWICE?). I guess I'm STILL mad...

But, by this weekend I can heat up the head and install the new, resized, CycleX guides and I'll be halfway guided. 

Bob L. found me someone who had a set of 12027-283-310 Honda guides (NOS) and I just sent off the funds: I sure hope it's not a scam that is subbing the later cast iron ones (12027-300-310) instead. It may be the last set of Stellite guides I'll ever get? Then I can hopefully slide them in and make me smile again!

[754]

Drill the top of the guides to just past shoulder or groove.. Knock top off, then drive into the port.... Bores should be shiny and scratch-free...and not go oversize..

[70CB750]

I would be looking for new head by now.

[HondaMan]

Worked perfectly!
Polished the CycleX oversize OD down with 400 grit and 1000 grit paper at 1000 RPM, made them all .0008" larger OD than their respective holes. #2 was the largest hole, at .0012" over spec. Heated the head to 275 in the oven ("Wow, that stinks!" when she caught me...) and sprayed some CRC freeze spray in each guide, oiled and tapped them in. Tomorrow will start the reaming and honing.

The CycleX guides remain at .258" upon their installation, which was the same ID they started with: they did not shrink any further. It should be fine then to run the .259" reamer through once, then the .260" for the intakes. I'll hone them to a .0005" to .0008" clearance: Honda's spec is 0.0005" to 0.0015" on the intakes. Going for max life (again) here, in the fight against ethanol (non-alcoholics, unite!).
 

[HondaMan]

OK, I may have to give up my search for Bigfoot...Stellite NOS guides for the exhaust... I thought I had found a set of 5 guides, at least the eBay seller thought he had the right ones. As it turns out, he can't read a vernier caliper (or didn't want to?) and although the guides are genuine Stellite NOS, they are for a CB/CL350 twin and a 450 twin pre-1970 - there are 2 different sizes of guides here!

Hope he will swap back for my funds. This is getting expensive!   

Along the way, I've sure found some interesting [sic] folks, most of whom are keen on 'selling NOS parts' whether they have the genealogy or not. I am also a little surprised, I think, at the number of people who think they know this stuff, but really don't. It doesn't seem to be their 'fault', but they really don't. 

So, unless I stumble across something accidentally by this Friday, I'm going to have to turn down the CycleX bronze guides for the exhausts, too. I just know I am going to miss those 20% longer exhaust guides in 20 more years of riding, as they really cooled the exhaust valves a lot better.

[Retro Rocket]

You couldn't make some guides Mark..?

[RAFster122s]

I would think some members here or on the Honda twins site would want them if you can't return them. Don't try to restore a CA77/78/95 or even an S90 as many of the sellers claim to have the correct cable, handlebars, or mechanical part but do not as Toytuff , Greggo,  myself, and many others have learned. Foreign or domestic sellers are either eager to sell and have no scruples or simply do not know what they have or have been duped by their sources/suppliers/distributors.

Sodium filled valves like those used on turbo motors are very good at handling heat. Wonder what an early Saab turbo or Volvo B21F turbo valves these are small turbo motors and wonder if they could be adapted. But, the stellite guides are superior to bronze at pulling heat off the valve, that is the property you want. What do modern turbo motors use for valves and valve guides? Is it the same as the early turbo motors with sodium filled valves and satellite valve guides and satellite valve seats?

If stellite was easy to machine it would be easy to resize, but it is hard and brittle.

[toytuff]

Don't try to restore a CA77/78/95 or even an S90 as many of the sellers claim to have the correct cable, handlebars, or mechanical part but do not as Toytuff , Greggo,  myself, and many others have learned. Foreign or domestic sellers are either eager to sell and have no scruples or simply do not know what they have or have been duped by their sources/suppliers/distributors.

Amen.

tt

[bambuhiphop]

OK, I may have to give up my search for Bigfoot...Stellite NOS guides for the exhaust... I thought I had found a set of 5 guides, at least the eBay seller thought he had the right ones. As it turns out, he can't read a vernier caliper (or didn't want to?) and although the guides are genuine Stellite NOS, they are for a CB/CL350 twin and a 450 twin pre-1970 - there are 2 different sizes of guides here!

Bummer. Sorry they weren't right.