Topic: CB400T Refresh - Spring Project

[KB02]

So it has come time that my wife's bike need a little bit of love. I figure that I might as well document the process. AND, since we all love pictures:


It's a 1978 CB400Tii, the Hawk. I had replaced the head gasket a few years ago and when I did so it upset the cylinder base gasket which started to leak. This has caused some really nasty discoloring on the top of the engine case:


Since I have to pull down the top end, I figure it might not be a bad plant to clean the whole thing up while I'm at it.


I figure that a little elbow grease, some Brillo pads, a buffing wheel and some grey paint will do the little engine wonders.

[hoodellyhoo]

Looking forward to it! My dad's third bike was a hawk. I hope the chance to ride one someday. Seems like it would be fun.

[KB02]

Engine out and beside the bike.


Some better pictures of what I hope to make look better:

[KB02]

My new toy. 


Helped turn this:


Into this:

[MoMo]

Nice work on the cover, and the 400/450 twins were great bikes-fairly light, very reliable and  quick. In this high gas economy it is a really economical commuter...Larry

[iridebikes215]

what kinda polish did you use on that cover? Looks great!!!

[KB02]

Rouge polish compound with a knit buffing wheel.

[KB02]

Been delayed in the cylinders. They were stuck pretty good and did not want to come off. I finally got them off, though. A 1"x1"x1' piece of PT wood and a sledge hammer finally did the trick and didn't break any fins.    Heat was the next thing to try, but it looks like I won't have to go that far. Tuesday is my next day off, so it looks like I will be back to grind stone (or buffing wheel... as it were...) on Tuesday.

[KB02]

Down to the crank case - and a bit of a before and after on cleaning up the pistons:


Head and jugs:


And a bit of before and after of the combustion chambers:


There was a TON of carbon build up in that engine. This is going to be like giving an asthmatic new lungs.

[KB02]

Okay, I've got a small problem. The o-rings that go around the cylinders don't fit. DO you think I'd be okay going without them? Or should I order new ones from Honda?

[MoMo]

Okay, I've got a small problem. The o-rings that go around the cylinders don't fit. DO you think I'd be okay going without them? Or should I order new ones from Honda?

Did the old ones stretch?  Not sure why but Honda has them there for a reason, possibly to prevent blow by at the outer sleeve...Larry

[KB02]

Block is looking better:


So is the head.


I thought about painting it black, but since I haven't really done any work to it, I figured I'd leave it silver.

Got the day off from work tomorrow. With any luck I'll have the engine mostly back together and back in the frame.

[KB02]

Valve cover painted.


And back in the frame:

[KB02]

Finally got back to the bike. Our trip to Americade is coming up so I had to get cracking on it.

I'm pretty happy with the results:


All together now...


It's not a huge thing, but it certainly does look nicer and it should run a little better now that I have scraped all the carbon build up out of the thing. 

Next step is new fork seals and tires and I am good to go.

[hoodellyhoo]

So did you start it up and run it yet? Any leaks or all good to go? I would really love to try one of those bikes sometime. I like the way their engines sound.

[KB02]

Started it up, ran it around the neighborhood for a quick ride. I really need to do a carb sync now, though. The rubber manifolds have an o-ring between them and the head. One of them was cracked and had shrunk leaving about a 1 cm gap. I've got a feeling that it didn't help the balance of the engine much.

[KB02]

Brought the bike in for judging at the Americade rally in Lake George, NY. I think I got robbed out of 3rd place (first and second were deserving winners), but I take home as a prize the fact that I think more people stopped and looked over our little '78 Honda 400 then the 1930's Indian that it was parked next to. 

Plus, on the ride to AND FROM the judging, I had other riders pull up next to me and comment on the bike. We may not have a trophy to hang on the wall, but I will certainly take the attention that I got as a prize.