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Discussion Starter · #1 ·
I bought this bike a couple of years ago. It's got low compression on the left cylinder and needed a cosmetic clean up so it's now apart in my garage. I took the engine apart and it looks worse than I expected. It already has .75mm OS pistons and they are worn out, cam chain adjuster was at the end of it's travel. I'm going to do some measuring tonight to see if the crank is junk but I suspect it is. At least I have a couple of spare engines, maybe I can make 1 good one.













I'll let you know how it goes.



 

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Wow !!

That's a confusing bike!!

Look to be CL K5 exhaust, CB K1 tank, CBK2/K3 side covers, CBK4 engine (with chain oiler, it looks like), CL brake pedal, and maybe a late CL front end??

What's the frame number on this bird??
Is that front wheel 18" or 19" ??
Does the seat hinge at the rear or on the side??

I'll have to say, though, I really like it !!!

I wish I could find a really nice K1 tank like that !!

Fix it, man, fix it.
 

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Discussion Starter · #3 ·
Thanks Bill, yeah it's definitely a Heinz 57. The frame number is CB450-4101737. I was wondering what that thing on the output shaft was. Is that the chain oiler? I love the look of the bike too, that's why I paid too much for a bike with a sick engine. The seat hinges at the rear and it has a 19" front wheel. I did some measuring on the crank and rods today and it looks like the crank is OK. I thought there was too much wrist pin to rod small end clearance but when I measured the small ends they are .6710" and .6708". The Honda manual says replace if over .6721". I found no radial clearance in the main bearings or the rod big ends. The "rod tilt" measures .037" and .039". The rod big end side clearance is .013" and .012". Is there a spec for crankshaft end play? Mine seems to have a lot. Do you know if there is a recommended place on the piston skirt to measure the diameter? These seem very barrel shaped and the largest measurement is about 1/2" from the bottom of the skirt. Do you know what the recommended piston the cylinder clearance is for new pistons? The manual does not seem to have a spec for piston to cylinder clearance. These both measure .0055". I have a new set of 1.0 mm over pistons and rings and all the gaskets and seals but I'll need a cam chain and some wrist pins and circlips. I also have 4 new valves and valve seals and I have a good head with the seats already refaced with a 3 angle valve grind. So I'm just about ready to go after the cylinders are bored. I'm looking forward to getting it back together, hope to be riding it in the spring.
 

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I bought a cam chain from an Ebay seller that was very reasonably priced. He even included 3 extra master links for a $1.00 each. Not too bad.

Georgefix was the sellers name. You'll see it if you search for cam chains on Ebay..

GB :mrgreen:
 

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johnnyc14 said:
Thanks Bill, yeah it's definitely a Heinz 57. The frame number is CB450-4101737. I was wondering what that thing on the output shaft was. Is that the chain oiler? I love the look of the bike too, that's why I paid too much for a bike with a sick engine. The seat hinges at the rear and it has a 19" front wheel. I did some measuring on the crank and rods today and it looks like the crank is OK. I thought there was too much wrist pin to rod small end clearance but when I measured the small ends they are .6710" and .6708". The Honda manual says replace if over .6721". I found no radial clearance in the main bearings or the rod big ends. The "rod tilt" measures .037" and .039". The rod big end side clearance is .013" and .012". Is there a spec for crankshaft end play? Mine seems to have a lot. Do you know if there is a recommended place on the piston skirt to measure the diameter? These seem very barrel shaped and the largest measurement is about 1/2" from the bottom of the skirt. Do you know what the recommended piston the cylinder clearance is for new pistons? The manual does not seem to have a spec for piston to cylinder clearance. These both measure .0055". I have a new set of 1.0 mm over pistons and rings and all the gaskets and seals but I'll need a cam chain and some wrist pins and circlips. I also have 4 new valves and valve seals and I have a good head with the seats already refaced with a 3 angle valve grind. So I'm just about ready to go after the cylinders are bored. I'm looking forward to getting it back together, hope to be riding it in the spring.
The piston to cylinder clearance you measured is a bit much, though Honda lists no values for it - Terry Naughton has mentioned 0.0015"-0.002", which is what I've always heard as a standard value. Just as important is the cylinder "taper", or the difference between the bore at the top and bottom of the cylinder - the manual lists a very small spec for this, less than 0.0002". That's the reason I bored my own 450 out.
When you get it bored out, take a copy of the manual pages with you and the machinist will know how to bore them for proper clearance.
Incidentally, the con rods do not connect to the pistons dead center either - they're off set by 1 mm towards the intake side, so that the momentum carries it through the top of the stroke.

The pistons are not supposed to be round - they are "thicker" facing front and rear, to make up for the expansion of the extra metal around the con rod pins on the sides.

I have never seen a spec for crankshaft sideplay anywhere. If you have significant sideplay even with the oil filter and alternator attached and the cases together, I'd think about a different crank myself. Been there, done that.

With that said, if the pictures are accurate, it's still a pretty darned nice bike. No rust, great exhaust and seat, and generally in real good shape, very clean.
I'd say if you paid $800 or less, you did well. You can fix the engine and still have about $1,000 in it, which is pretty good.
And that K1 tank is a killer, dude !!

By the way, the frame is a CBK4, like the engine.
And I was wrong - those are K4 air cleaner covers.
So looks like someone spliced in a bunch of CL parts to a CBK4 - that seat is also proper for a K4.

Yeah, that's the chain oiler there in the end of the countershaft. I replaced my countershaft with one from a K2, which had no chain oiler. In the past, I've just removed the whole thing, sprayed the inside of the countershaft with carb cleaner to get oil out of it, then plugged it with silicon.
The chain oiler is a huge, messy pain in the butt, I have no idea why Honda did it.
 

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Discussion Starter · #6 ·
Thanks again for your help Bill. I have another complete engine that I'm going to check the crank on this weekend and see if it has the same amount of end play. I noticed in the Honda manual that if I subtract the new piston diameter listed as 2.754-2.755" from the new cylinder size 2.756-2.7564 the difference is about .0015-.0020". That sounds like a reasonable number.
 

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johnnyc14 said:
I noticed in the Honda manual that if I subtract the new piston diameter listed as 2.754-2.755" from the new cylinder size 2.756-2.7564 the difference is about .0015-.0020".
Duhhh...

How come I didn't think of that??
Just goes to show you, two heads are better than one (no pun intended) ....
 

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Discussion Starter · #9 ·
Thanks Allen. I removed the clutch cover and alternator cover from my spare engine and found that it has the same amount of end play as this engine. I decided to split the cases and check the crank thoroughly. I'm glad I did, the crank bearings look like new and the run out is good. The transmission gears and bearing are also in great shape. There's about 1/4" of sludge in the bottom of the sump though. On Monday I'm going to take all the part to work and put them in the Storm King parts washer. I got the frame out of the storage shed and I going to start assembly of the chassis this week.











The pile of parts just keeps getting bigger!
 

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Discussion Starter · #10 ·
Bird76Mojo said:
I bought a cam chain from an Ebay seller that was very reasonably priced. He even included 3 extra master links for a $1.00 each. Not too bad.

Georgefix was the sellers name. You'll see it if you search for cam chains on Ebay..

GB :mrgreen:
Thanks again Bill, I bought a cam chain from Georgefix for $25.00. Wrist pins and clips I can get from my local Honda dealer still.
 

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Discussion Starter · #12 ·
Well, after disassembling both of my complete engines and sorting through all the other loose parts I find I need 1 cam chain roller. If any one has a better one then this for sale let me know. I have lots of other engine parts if anyone needs something or want to trade.





 

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Discussion Starter · #13 ·
Well I got lucky and found all the cam chain tensioner parts on e-bay today and won the auction. They look really good in the pictures.









I also took the cases, head and cylinders to my work and put them in the Storm King parts washer which is like a giant dishwasher for grungy vehicle parts. It took over 3 hours but the part came out very clean but still look like 40 year old aluminum. I decided to paint them using aluminum engine paint. I looked at the pics of Bill's CB200 and decided to use the Duplicolor Engine Enamel he suggested. I haven't decided yet if I'm going to paint the clutch and alternator covers or polish them. Here's how they look after painting.







I have 2 sets of cylinders, 1 standard bore and 1 at .75mm over. I have a set of 1.0mm over pistons so I'll take the already oversize cylinders to the machine shop tomorrow and get the pistons fitted. I'll wait to paint them until after that. I have both sets stacked on my bench and i thought they looked kind of cool like that.



My local Honda dealer had wrist pins and clips in stock (they must fit other models) at a reasonable price so I got those too. It's all starting to come together!
 

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Engine paint looks sweet. Keep up the good work and keep posting pics. I'm currently restoring a 72 CB350K4. My engine is at the shop getting top end overhaul. They told me that the cam chain tentioner needed to be replaced and I was able to buy a new one from a web site. BIG BUCKS $100 with shipping. The side covers and tank are out getting paint. I'm dying to get them back cause everything else is done.

Keep up the good work!

Matt
 

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Discussion Starter · #15 ·
Thanks Matt, I had a look at your pics. Looks like you are an ace at polishing aluminum. What products are you using? I've got a brass wire wheel and a rag type polishing disc on my bench grinder and I'm using various grades of polishing compound. It's a lot of work!!
 

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John,
No doubt polishing aluminum IS a lot of work but I think it's worth it. I came up with a 6 step process for turning rusted/tarnished metal into a Chrome like shine. Here is my secret:

1. Scotch brite wheel i.e Paint/rust/grime/tarnish remover
2. Black Rouge on Sisal wheel
3. Brown Rouge on Spiral Sewn wheel
4. White Rouge on Spiral Sewn wheel
5. Liquid white rouge, swirled around with a clearn rag, then
6. Maas Metal Protector

I use a drill attachment, no fancy set up here.

For the parts that have the factory clear coat on them, instead of step 1 above, I use "Aircraft stripper" to get it off. Then depending on the condition of the piece I sand it with a variety of wet sand paper up to 2000 grit. Then continue with steps 2-6.
I'm using Maas Metal Protector for the first time so I don't know much about how long it will last before oxidation will start agin. I'm thinking I will clean the bike and reapply it every few months. We'll see only time wil tell.
Like you I had a decent bike to start with. I rode it for three years mostly commuted to work with it, 28 miles of back roads one way. I just wanted to spiff it up a little bit.

Matt
 

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Here is my other bike, 1975 CB550K1. I was lucky enough to get this one for free from a co-worker. I repainted the tank and side covers and polished it up last winter. Once I saw how polishing made a world of difference it wasn't hard to say, I'm gonna redo my 350 too. Unfortuneately I do not have before photos of the 550.
What do ya think???





Matt
 
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