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'70 CB 450 Has Arrived

1500 Views 9 Replies 4 Participants Last post by  Bird76Mojo
Well, I took delivery of my new '70 CB450 Project. My intent is to make this a longer term project in such a way that I can ride it most of the time. I'll try and post up some good pictures of the "as unloaded" condition.

Right away there are a few things that I need.
  • The adjustable clubman handlebars will be replaced (they're in very good condition if someone has a good set of stock CB450 bars they want to trade.
    The fork boots are torn/missing but it looks like those are still avaliable from Honda.
    I won an auction on eBay tonight for a Tach that some scuffing on the side case but I think I can swap the case with the good one from the existing tach. Either way, for $$20 I couldn't pass it up.
    It needs a battery too but kick starts pretty easily.

The biggest problem is that it doesn't have any grunt and runs poorly. It starts easily and idles smoothly but is lacking power. I did a compression check as soon as I got home in the dark driveway and found the right side at 160psi and the left at a measly 100psi. Sooooooo, it obvious what I need to attack first. Before I get all depressed, I'll check the valves tomorrow to make sure they're not too tight. The top end is very quiet so I can't tell anything from just listening. The condition of the spark plug holes was miserable and I had to use a thread cleaning tool to get the plugs back in without excessive binding.

The other symptom that tells me it might not be the valves is that it's blowing significant smoke out of the breather tube and it's pretty oily down at the breather tube exit.

I got a Clymer manual with the bike so I need to tear into that quickly since I've read hear (and elsewhere) that the valve adjustments can be more difficult than the average valve adjustment and certainly more critical than my CL350.

I took some grief from my wife over how much I've spent on the CL350 so I promised I'd do this one on the cheap, (or at least as cheaply as possible for me). :)
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66Sprint said:
Mike....The MINIMUM allowable compression on a 450 is 164 PSI ... Given the non-standardization of COMP meters,(+or- 5 PSI), even your BEST cylinder still needs rebuilt... A "fresh" engine will read in the 180 range and go as high as 210 to 215 once the rings "seat"...... The Smoke is probably from blow-by from the 100PSI cylinder, and the thinned oil the fuel getting by it is allowing... DON"T RUN IT anymore!..... The starter clutch problem can usually be fixed with new caps, springs, and rollers, (I believe all are still available from Honda), or I've been told it can also be caused by a weak battery......
If you don't already have it, Bill's annotated manual is the one to get (on CD).....
Keep us posted as to your progress.... Steve
Can the head and cylinder be pulled without pulling the motor out of the frame?
66Sprint said:
Nope..... :(

Bird76Mojo said:
What condition is acceptable on the 450 bars? I might have a set for ya!

I've also got a NOS set of fork boots still in the bag with part number, that I'm not going to use. I'll try to find out the price from Honda and beat it for ya.
No rust, no pitting minimum scratch.

Let me know on the price, inc. shipping, on the boots.
Bird76Mojo said:
I'll have to go out to the shed for the bars, but here's a link for the fork boots:

Here's another recent sale on them: ... 0005r12109

Those look to be $49.99 plus shipping, so is $45.00 shipped (TOTAL) too much to ask??? I'll even throw in the bars if they're in good enough shape, if you send me yours... I forget what I paid for the boots years ago, but they're NEW in the bag and have been stored indoors with heat. My back room has served well as a NOS parts storage facility!! :lol:
Thanks for the offer for the boots but I picked up a set locally. I had to go to the Honda shop for some other rubber parts they needed and he gave me my 'Racer Discount' so I got the boots for $25/ea plus some other things that I needed like tail light mounting rubber and rear turn signal mounting rubber grommets.
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