1965 Honda CB450 Black Bomber Oil, oil filter cleaning technique and OCI?

[bob555]

So, I have a sort of partially restored 1965 black bomber, actually a particularly early one at serial number 1657.

Cast into the alumnimum case, it says to use 30wt over 50 degrees, and 20 weight below, and that the oil capacity is 2.3L. It seemsly like everyone runs a thicker oil in vinatge bikes, so I ran it on 15W40 delo and Rotella T last summer, and this year I have 15W50 yellow cap mobil 1 in it (it was on sale for $4.50/qt). Is this an OK oil choice? I'd just assume not glaze a clutch since the early 4 speed models are particularly hard to find clutch and transmission parts for.

Dumb question, but if anyone actually has a vintage honda, where's the oil supposed to be on the dipstick?

How often should I change the oil? I did a couple of quick changes last summer since the bike had sat for 30+ years, but now I would imagine things are reasonably clean in there.

Finally, several good honda mechanics I know advised never cleaning the centrifugal oil filter, but I think they were more concerned about mouth-breathers that put the cover on indexed wrong and destroy engines with the resulting 0psi oil pressure. I've wiped out the filter once, and there was only maybe 0.025-0.050" of sludge in it and no metal visible metal. Should I mess with the filter at all? How clean should I try to get the housing? I just wiped it out with papertowels last time, without using solvents or anything.

 

[ddrumman2004]

My oldest son has a 76 Honda 500 which is basicly the same engine as the 450 and he runs a 10w-40 synthetic in it with no problems.
He is restoring the bike and rides it daily when he can.
He asked a Honda dealer in Memphis about replacing the rear tire as it is dry rotted and the dealer told him they couldn't do it as they didn't have a shop manual for that bike. What a bunch of morons!

Other than needing tires, the only other problem is the charging system putting out low voltage(11 volts). A new regulator may fix that.

 

[bob555]

So, how often does your son change his oil, and does he clean the filter? And where's the oil supposed to be on the dipstick?


A couple very off topic suggestions for your son:

A. Don't drive on dryrot! Change the tire yourself. Changing tube-style motorcycle tires is pretty painless and fast, and at most, you'd need to buy a ~$10 set of tire irons. There's good instructions on the internet, etc about actually doing it. I bought a set of Kenda Challengers and Tubes for about $100, and changed them myself in a little under 2 hours having never changed a motorcycle tire before.

B. If he has charging system gremlins, swaping to a vastly more advanced, and $5!!!! radio shack rectifier would be high on my list. There's good info, and high quality help over at the MSN group and the DOHC website if he needs it.


C. IMHO, On all DOHC Hondas...remove the head steady to cut down on vibration, but espicially it should be done on the vibration prone 500T's. It was even a dealer mod, sort of like a TSB back in the 70's.

 

[wileyE]

Unhook and clean (wd40) all the connecters between the stator and the reg/rect. Make sure the reg rect is grounded well also. Sometimes following the wiring is hard, as close as the two parts are it'll often go all the way into the headlight bucket and come back. Lots of places for the connection to be bad and the cause of 90% of the failures of stators and reg/rect.

 

[oddrodtodd]

quote:

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Originally posted by bob555:

Dumb question, but if anyone actually has a vintage honda, where's the oil supposed to be on the dipstick?

---

I had a '65 Trail 90 (push-rods and the old fashioned swing-arm front suspension with about an inch of suspension travel). It had a pinched section at the very bottom of the dipstick about a 1/4" in length. You were supposed to fill it up to the point where the pinched section ended and the regular shape returned. I don't think you were supposed to screw it in to check the level. Just rest it at the top of the threads.

Todd

 

[ddrumman2004]

I wound up buying the 500T from my son and as for the charging system.....bad stator....but have one on the way.
As for oil level, I will look it up in the owners manual as the bike came with the original one!
That alone is worth some money I bet.

 

[XS650]

quote:

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Originally posted by bob555:
So, I have a sort of partially restored 1965 black bomber, actually a particularly early one at serial number 1657.

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My older brother had one of those when they were new, think it was about as early as yours. He got a CB750 after that that also had a S/N under 2000.

The black bomber was a neat bike. I don't remember the details of cleaning the filter, but my 1969 CB350 has a similar whirly filter. I just wiped it out with a clean rag each time I changed the oil.

 

[dwendt44]

I have had a CL 350 with a cintrifical filter(?).
I used brake cleaner to flush out any residue, let it dry, and put it all back in place.
Never had any oil problems.

 

[Titan]

Centrifugal

 

[RF Whatley]

Bob555 & others -
I was a Honda dealership line mechanic in the early 70's and actually went to Honda school on the 350 and 450 models. It's an amazing machine. Here's what I would like to share with you...

1. There is one HUGE Achilles’ heel to the 350 and 450 and that is the oil pump, but not like you'd think. The problem is slow delivery. While the crank and rods are all ball and roller, the cams run directly in the 4 aluminum "cam bushes". There is no babbitt, it's simply steel on aluminum. And because of the design of the pump, the cam bushes are the last place to get oil. In fact it can take 45-60 seconds OR MORE for oil to reach the cam bushes. You can actually hear the valves get quieter when the oil finally arrives!

If you see a guy rev an early Honda just after starting you can know it's fixing to give up. The lacquer on the polished exterior turns yellow, because the bushes get so hot. We called them "gold plated" bushes.

So the secret to long Honda 450 life is to let the machine idle for the first minute after the first cranking of the day. No “throttle jacking” what so ever. If your bike won’t idle, then open the throttle to 1200 RPM or so.

2. The oil filter is a great idea and really only needs cleaning about every 3-4 years. However you can’t get anything out of it with a towel. The stuff is REALLY packed in there, so you have to use a screwdriver blade. It will come out in hard chunks about the consistency of pottery.

3. Most “classic bikes” run solid weight oils because most older bikes are European and run piston clearances like .004-.006 inches. All Hondas of this era run less than .001 inch, so multi-grades are the key. I’ve actually seen Hondas seize pistons running 40W oil even after being properly warmed.

4. There will be other posts here about roller cranks. Due to the “chopping” effect the ball and roller bearings have on dino oils, you’re much better off with the synthetics. In fact where cars may have nothing but plain bearings, a Honda 450 may have 15 or more if you count the mains, rods and all the ones in the gearbox.

Hope this helps!

 

[RF Whatley]

PS. You screw the dip stick all the way in.

 

[ddrumman2004]

I quote this from a 1975 Honda CB 500 Twin owner's manual on changing the oil:
"Check the oil level with the filler cap dipstick; however, when making this check, do not screw in the cap. Oil level should be between the upper and lower marks (page 34) on the dipstick. When checking the oil make certain that the motorcycle is in upright and level position."

 

[jsharp]

Whatley pointed out some issues with the older Honda engines that have some merit. I worked on a lot of them and IMO the valve system was the worst of all things.

They were roller bearing lower end engines with rocker arms and a plain bearing camshaft in the 350, or 2 camshafts in the case of the 450 running directly in the head casting. Limited oil capacity that also included the transmission and clutch with just a "spinner" instead of an oil filter.

The 450's had the same oiling issues to the top end that the 350's had only worse thanks to the additional cam and the cylinder head setup, with the added "benefit" of a cam chain and tensioner that was marginal.

You really don't want thick oils in these engines. 10W-40's worked fine back in the day. A modern HDMO or synthetic 10W-30 might in fact work well given how much the old 10W-40 oils sheared. Anything thicker will give you higher oil temps and longer times to get oil to the top end with no benefits I can think of.

The factory valve clearances were really close, IIRC .001" - .003" though we always used to use .002" - .004" for the exhausts. As pointed out, the piston to cylinder clearances were about 1/2 of the rule of thumb of the day which at the time was roughly .001" of clearance per inch of cylinder bore. Another reason why you don't need or want a thick oil.

You'd think these things would be a recipe for disaster but Honda made this all work by using high quality components like like ART cast pistons and good quality valves and rocker arms, plus very precise assembly for the period. I saw one CB450 that had 45,000 road miles with little care other than 2K oil changes with dino 10W-40 and the engine had never been opened up. Try finding that on a Harley or Brit bike of the period...

[ June 19, 2006, 05:58 PM: Message edited by: jsharp ]