1972 Honda CB450 Cafe/Brat inspired build

And I've run into a problem with one of the carbs. I cannot for the life of me figure out how to get this vacuum piston out of this carb. The other one slid out just fine, but this one is definitely stuck. I am up for suggestions.

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Also, haven't seen this part in the manual at all, is it supposed to be in there?

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I should note that both carbs had one of these in there and they are both cut like that.
 
Depends on the material and what you want it to look like in the end. With aluminum, I used 160-180 grit sandpaper and cleaned up the surface and got all the brush marks going in the right direction and then went over that with some scotch brite. The hardest part is making sure all the brush marks are in the right direction. After cleaning I then sprayed the part with a clear high heat engine enamel.

Just try out some different grits and the scotchbrite and see what you like.
 
I don't know what that part is. There is a seal there but it is thin and is between the piston and the carb body. Maybe the PO wanted to add some weight to the piston to change the throttle response or something.

As far as the piston sticking, I would guess the alignment key has corroded and is stuck. On your other piston you will notice a groove on the smaller part that slides into the body. In the body, you will see a small protuberance that keeps this piston from rotating. I bet that is all corroded. Maybe soak it some more or try some CLR or something?
 
Flugtechnik said:
Depends on the material and what you want it to look like in the end. With aluminum, I used 160-180 grit sandpaper and cleaned up the surface and got all the brush marks going in the right direction and then went over that with some scotch brite. The hardest part is making sure all the brush marks are in the right direction. After cleaning I then sprayed the part with a clear high heat engine enamel.

Just try out some different grits and the scotchbrite and see what you like.

Thanks, I was hoping to get away from having to do it by hand but it seems thats gonna be the only option. Haha
 
reesea17 said:
Thanks, I was hoping to get away from having to do it by hand but it seems thats gonna be the only option. Haha

There may be a way to do it with a machine, but I didn't find one with the tools I have. This was a labor of love and took many many hours. Usually I would just work on a part while watching TV with the family or whatever.
 
Okay, first things first.

I was able to get the float piston out with a 2 part water 1 part CLR bath for roughly 3 minutes. All fine an dandy until I startng trying to remove more of the parts. Previously seized parts were coming apart and then disaster struck and one of the jets heads stripped. I'm at a loss for what to try and do.. any suggestions?

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I also went about trying to use a screw extractor on the final two bolts that are keeping me from removing the cams etc from the head. Problem is that it didn't work and I am again at a loss for what to do in this situation. I am again open to any suggestions you may have.

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Also, just received a petcock that I bought for $10, not a bad price but I'm sure it'll need to be taken apart and rebuilt. Question is, I have seen in pictures on DCC that the petcock for my tank has two little pipes that go into the tank? what is the smaller one for? do I need it, if so can I buy it somewhere or should I just try to fab one?

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Finally got the bolts off of the covers and was able to get at the carb side cam and rockers. Cam looks pretty good and I'm assuming the rockers do too, not a hundred percent on this though. Seems to be a small pit in one, however it doesn't look like it'd hurt anything.

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Still trying to get at the exhaust side cam, came to the computer to figure out how to remove the points completely...
 
Alright, got the points off and the other cam out and had a little bad discovery. Looks like one of the cam followers took a good beating on the left side. Thinking this could have something to do with the hole in the left piston head? The cam itself doesn't actually look that bad. Still feels smooth just looks a little rough.

Is this cam follower savable or should I start looking for a replacement?

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I wouldn't put either the rocker nor the cam from the LH side back in, if it were me. Those only go from bad to worse, unfortunately.
 
That follower is toast. The exhaust side is usually the first to go. I will see what condition my extra followers are in but I think they are extras because they were bad as well. I don't know about the cam. I have a cam from a CB500t. I checked part numbers and it is the same (14120-292-013). I will try to take pics this weekend. If it is good it is yours. I don't know how to check them.

Take profile shots of the other followers. They are probably alright. Finding followers for these things is like finding bigfoot humping a unicorn. I had to buy an entire head off ebay just to get the followers, hence the extra camshaft.
 
Flugtechnik said:
That follower is toast. The exhaust side is usually the first to go. I will see what condition my extra followers are in but I think they are extras because they were bad as well. I don't know about the cam. I have a cam from a CB500t. I checked part numbers and it is the same (14120-292-013). I will try to take pics this weekend. If it is good it is yours. I don't know how to check them.

Take profile shots of the other followers. They are probably alright. Finding followers for these things is like finding bigfoot humping a unicorn. I had to buy an entire head off ebay just to get the followers, hence the extra camshaft.

Thanks a lot! That would save me a huge headache as I can't find any followers online anywhere. Found a set of camshafts that look like they are in really nice condition and going for $60 which if far less than other posts. So if all else fails it looks like I could nab those. Still having a rough time finding any pistons at OS bore.
 
From every I've been seeing online and how hard it's been for me to find a set of pistons for this bike in any size. I've run across this listing and even though it doesn't express what year it is, to me it looks like a pretty great deal.. Says the sleeves are bored out to .75mm. Doesn't say anything about the piston size but I've messaged the seller. $175 for cylinders, pistons, rings, and clamps...


<a href="http://www.ebay.com/itm/Honda-cb450-cylinder-and-pistons-/390527483057?pt=Motorcycles_Parts_Accessories&hash=item5aed407cb1&vxp=mtr">Ebay Link - Cylinders and Pistons</a>
 
reesea17 said:
Thanks, still needs a good bit of work on it to get the rest of the paint off.

I've got a question about batteries. I'm a little confused at what size battery I will need. I'd like to get as physically small a battery as I can, but I have no idea what to look for past that it needs to be 12V's.

I want to run the following:
Electric starter
Horn
Headlight (Possibly an HID retrofit)
Two bullet size LED taillights
LED license plate lamps

Thats all I can think of right now.. Kinda want to go bare bones on this build.

As far as small batteries go, I'd just say drop the $120 on a Shorai lithium battery and keep rolling.

And if you end up going with LED turns, remember to get a modern flasher relay and deal with the indicator bulb in the dash.
 
manualofman said:
As far as small batteries go, I'd just say drop the $120 on a Shorai lithium battery and keep rolling.

And if you end up going with LED turns, remember to get a modern flasher relay and deal with the indicator bulb in the dash.

I'm still slightly confused at what A/h rating I should be looking at in a battery though. What would be sufficient?
 
Little update for the build.

Got a good amount of ordered parts in: Engine gasket kit, Engine Oil seal kit, Engine stainless steel fasteners, Carbs SS fasteners, Carb rebuild kit, and some 11" shocks from DCC. During a quick test I've noticed that the shocks eyes don't fit onto the bike shock mounts, and I know I bought them from DCC specifically for my year and model bike.. Is there normally an amount of modification needed? There was a metal piece inside the rubber grommet, took that out and it still doesn't quite fit. Not sure I'f maybe I ordered the wrong part of it I'll need to trim out the grommet a little to make it fit.

The carb rebuild kits came with a lot more o-rings and washers than I have found on my carbs, and I was wondering if anyone has a link to a post on the rebuild of one of these carbs. I found a blog post for CB360's thats fantastic and would love to be able to find one for my model.

Also got in a set of .75mm bored cylinders, .75mm OS pistons, and .75mm OS piston rings. Things are coming together, now I just need an exhaust cam and cam follower.

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Also, on a side note, I just wanted to get opinions on this. My tank came with a pretty sizeable dent in the top of it. Since it couldn't be easily popped out and would take a gallon of bondo to fill, I decided to even it out and cant decide if I like it or not. It slightly looks like its supposed to be there now but I'm unsure as to whether or not it looks good, or will look good once painted.

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Looks kind of weird, maybe even it out more towards you while you're on the bike? The random circle dent I mean
 
edukaycheon said:
Looks kind of weird, maybe even it out more towards you while you're on the bike? The random circle dent I mean

Yeah thats kinda what I was thinking too, but now I'm slightly scared of just ruining it completely. I could always look for another tank but that would be pretty expensive I'm assuming.
 
Maybe if you also added knee dents it could look more even and intentional? You could always put a drink holder there...
 
mikewerx said:
Maybe if you also added knee dents it could look more even and intentional? You could always put a drink holder there...

Haha now thats thinking outside the box..
 
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