new cafe build cb450

MJPriceisright

Coast to Coast
hey, been reading a bit for the last couple weeks on this forums, just wanted to share my story and my new project.. been riding sport bikes since i was 18, (currently 27) but have recently just fallen in love with that old school cafe racer style. so thats where im at, went out and picked up a 72 CB450, and going to fix it up.. found it off craigslist, guy had no idea how to mod or build bikes and said he bought it from a auction or something.. i was pretty excited cause i was getting it for pretty cheap and it had everything i needed to get started.. until i tried to kick it over.... damn. he had already told me it had been diagnosed with low compression, and it currently didnt run. but when i tried to kick it over to make sure it wasnt seized, wouldnt kick.. anyways.. thats where im at, tore it down basically to the frame yesterday and im going to build it back up from the frame. here are some pics, im sure i will be all over this website looking for more information and asking questions, thanks!
 
got the engine to turn, hoping the rings were maybe just frozen to the cylinder walls.. but started my tear down, pretty excited, here are a couple pics.
 

Attachments

  • IMG_0993.JPG
    IMG_0993.JPG
    274.6 KB · Views: 589
tear down and "box O crap"
 

Attachments

  • IMG_1007.JPG
    IMG_1007.JPG
    311.5 KB · Views: 589
  • IMG_1057.JPG
    IMG_1057.JPG
    298.7 KB · Views: 553
  • IMG_1059.JPG
    IMG_1059.JPG
    163.1 KB · Views: 3,607
some new pics of the engine tear down, everything looking good, one of the pistons the rings were locked and compressed the whole way, could barely even seen where the break in the rings were... one small rookie problem, i dropped a wrist pin circlip down into the crank case, cause im an idiot, i even had a magnet pressed right against it, somehow is slipped and fell anyways... any ideas on how i should get that out? long magnet fishing? anyways, gonna dive into the soda blasting this weekend and get the motor cleaned up, painted, and back together this weekend. frame and swing arm are both out getting blasted at the moment as well.
 

Attachments

  • IMG_1115.JPG
    IMG_1115.JPG
    107.4 KB · Views: 3,527
  • IMG_1113.jpg
    IMG_1113.jpg
    50.7 KB · Views: 3,493
  • IMG_1112.JPG
    IMG_1112.JPG
    118.8 KB · Views: 3,595
  • IMG_1111.JPG
    IMG_1111.JPG
    123.8 KB · Views: 3,605
Slow down a little and think this one through. If you plan on blasting anything on that motor, you should completely strip it and then you can get it clean.

Just a couple of observations/comments/questions on the bike. Did it come with a title? If not, you might want to take care of that first.

The bars have been flipped which is a pretty good sign that the PO had no idea what he was doing. tires are old and crusty, but I'm sure you noticed that. rear wheel is a seventies chopper look. HD 16" rim and fat tire. You might want to change that for a suitable 18" rim.

That exhaust pipe appears to belong to a much smaller motor.

Do you have a clear plan and vision of what you are trying to achieve? It's good to have a plan. We don't want to see any pictures of showers of sparks as you grind off parts that the bike will actually need. Assuming that you want a bike that can be ridden safely and which will be fun to ride, think it through first and do a dry build first before you get anywhere close to paint etc.

Even the bozos @OCC know to dry build and do the fab work first and then break it down for paint and plating and do a final build. Even better to run it before paint to see what needs to be changed. That part is rarely shown on TV...

And good luck. Have fun creating your dream bike.
 
I have heard that soda blasting could be done to clean the engine without tearing it down. That is what I'm planning to do because no idea to tear down a perfectly working engine. Any thoughts on that?
 
My thoughts and others are not always the same, and I can't speak for anyone else, so here's my thoughts...

There's an argument that a complete motor can be blasted as one lump, as long as every orifice is completely and perfectly sealed. I always strip a motor to clean it. And if do get a case blasted, I still have to spend hours cleaning beads and debris out of all the threaded holes and nook and crannies.

The inside has to be spotless. The tiniest amount of glass beads inside a motor will wreck it in short order. looking at the pictures you posted, I'd suggest that there's nothing about that motor that says "perfectly working engine". Rings were rusted in place, intake ports full of crud.

You and I must have a different interpretation of the word perfect.

Yes. I am busting your chops. That's because I want you to have the opportunity to have a sweet running bike when you are done and not a frustrating pile of problems. Building a bike isn't a five minute job for any of us, but attention to detail pays dividends later on.

BTW, what was the answer on the title?
 
"slow down a little" teazer, your getting myself (MJPriceisright), and chheikki mixed up. i have had my hand in 10 second 4 cylinder turbo cars, and ive been amateur racing litre bikes for the past few years.. so i know exactly what im doing in terms of, "lets do this the right way, the first time" situations... ask anyone who plays with multiple stage nitrous setups, we know how to blow shit up. as for your questions. yes it has a title, its one of the most important factors when purchasing a project bike,car, motorcycle, recreational vehicle, whatever it may be.. yes i have an absolute vision on where i would like this bike to head, plenty of guys on these forums have inspired me and given me ideas for building up my own creation. and for you chheikki, my own two pennies, do what your time, knowledge and budget can afford. if you cant tear down a motor, then find a way to spray that bad boy together. i have read multiple threads about guys soda blasting and painting, its amazing how some of the engine parts come out after, im excited to do this myself. i personally dont feel like tearing the bottom end apart and doing the lower cases, so im going to be careful and do it all together most likely. but teazer makes a valid (slightly obvious) point that you dont want any foreign matter inside the motor. that goes for any motor big or small. but if your building a show bike, then spend the time and money to take it apart, and do it piece by piece..
 
You are correct that I managed to not spot Chukki sneaking in there.

You may be surprised how many bikes threads start with bikes without any paperwork.

Doing it the right way has nothing to do with building a show bike. I build race motors not show bikes and they have to be clean. Any street bike I work on is the same. :)
 
Yes I wasn't referring to MJPriceisrights engine to be perfect but to my own engine. I have a really low mileage 450 that is working perfectly and I don't see any point in tearing it down just to clean it up. Instead if the soda blasting is not a option I will let the engine stay as it is and polish some of the parts and clean it up in some other way. And I'm not skipping the engine tear down because of lack of knowledge in engines but just because there is no point in doing it now. I will do it later when there is a need of engine rebuild.

Here is a picture of my engine, maybe a good clean up with cloth and cleaner and polishing would be enough:
 

Attachments

  • SDC11695.JPG
    SDC11695.JPG
    820.9 KB · Views: 471
Man, I did the exact same thing with (dropped a piston clip) my motor last night. I got lucky because I was able to see it and snatch it out before it fell too far down int there.
 
I also dropped a piston clip into my bottom cases after rebuilding the 450 transmission last week too....
 
WELL AT LEAST I FEEL A LITTLE LESS DUMB, or just part of a new clumsy club. haha.. yeah chheikki the motor looks pretty good, and if mine was running and working properly i would be in the same boat as you, just clean it up and ride it.. i didnt attempt to take a look down at the time for the circlip, but this weekend i will start fishing around to see if i can find it.. oh well.. that seems crazy to buy a bike without the paperwork or title, i have seen plenty of people doing that in the sport bike world, most of the time the reason why there is no title, is because they picked it up off a five finger discount! HAHA
 
Love these 450's. Just finished going threw a 68 Black Bomber and digging it!
 
got a small update, i had recently purchased a new rear rim so i could get that 16" harley wheel off the back and replace it with a stock sized 18".. found a kawasaki wheel on ebay for 19 bucks in great shape, uninstalled the spokes and hub so i can re use the hoop, its in really good shape, now just need to find a spoke set for a cb, anyone out there got a spoke set for the rear rim? more updates coming soon.
 

Attachments

  • photo.JPG
    photo.JPG
    123.3 KB · Views: 1,810
  • photo 5.JPG
    photo 5.JPG
    127.7 KB · Views: 1,873
I just got a set of front and rear spokes off ebay from a dude in Taiwan. I liked them so much I bought 2 more sets. Price was right too. They were the thin ones though. I think for the race bike I'll get the thick ones.
 
hey guys, been away for a while cause of work etc, but im back to getting this bike project underway. engine is almost complete and back together, but i had a question on the head bolts. they are apparently stripped. they are a castle nut, but do i need to replace is with the same castle nut? or should i just get some good quality nuts, a couple of washers and torque them down to spec? any returned info is appreciated!
 
here are a couple motor pics of it going back together.. need to get it done so i can clean it up!
 

Attachments

  • photo_1.JPG
    photo_1.JPG
    156.5 KB · Views: 1,651
  • photo_2.JPG
    photo_2.JPG
    167 KB · Views: 1,656
  • photo_4.JPG
    photo_4.JPG
    150.4 KB · Views: 1,676
Back
Top Bottom