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Discussion Starter · #1 ·
Last week I accidentally won this thing on ebay. I low ball bid it just because it was nearby.





Cafe racer? Bratstyle Bobber? Just fix her and ride her? I'm not sure. My daydreams steer me toward a cafe style bike since I'm already cutting up a Yamaha XS650 for a bobber.

I'm just starting the thread to keep a journal. Things always change quickly at first and then slow down as I get further along.

So here's some initial photos of a bike that looks like it hasn't moved itself on its own power in over twenty years.





bigger since I like the light point flare off of the chrome:
http://farm5.static.flickr.com/4047/460 ... 8bc6_b.jpg
 

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Re: Where she goes, nobody knows. 1971 CB350

Have the seat reupolstered, oh wait stop.
Strip it down to the frame and blast it then powder coat it red.
Get the few pieces of bodywork painted black and polish all the aluminum.
 

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Re: Where she goes, nobody knows. 1971 CB350

please say your gona leave the cracked paint alone on the tank, that looks awesome!
 

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Re: Where she goes, nobody knows. 1971 CB350

I just can't seem to understand why anyone goes to the trouble to install ape hangers and a sissy bar on such a bike. What's the thinking ?
 

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Discussion Starter · #7 ·
Re: Where she goes, nobody knows. 1971 CB350

I forgot to mention the bike has 25,000 miles on the clock (at least the speedo that's on it.)

The engine was locked when I brought it home, but came free from rocking it back and forth in 1st gear.

Compression in cylinder #1 is 120psi and compression in cylinder #2 is only 20psi.

So I had an opportunity to buy one of four CB/CL engines two days ago. I sprung for a 1972 CL350 engine that had 5k miles on the clock and looks very clean. Compression in both cylinders is equal at 150psi cold and the engine was in a bike that was running a week ago.

So... I'm going to swap engines as soon as I have some free time and will be going through the process to rejuvinate it as time marches forth. I'm going to try to make my own custom seat cover to reupholster it, but I'm also going to work on my own cafe style seat. I've seen a lot of cool styles on this site and have some ideas in my head already.
 

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Re: Where she goes, nobody knows. 1971 CB350

Looks like a bike that is worth working on and fixing up to me. Those mufflers look like Harley take offs. I have a set from what I think was a Sportster and have plans to maybe put them on my 450. They almost fit as is I just need an extension from the stock header pipe to where the muffler will be when I bolt them to the same location that the stock ones are now.
Don
 

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Re: Where she goes, nobody knows. 1971 CB350

The Harley muffler is one I put on there just to see what it looks like. I've had em laying around forever since you can buy them dirt cheap in the winter on ebay.

I ended up winning a set of factory pipes and mufflers on ebay yesterday, so they'll be here next week. The mufflers have holes in the bottom at the tips like nearly all of em. But they will look better.

The Harley shop here actually accumulates the stock mufflers in piles and calls a salvage yard every now and again!! So if you want some, check your local shop for 'junk parts.'

I just got back from the DMV and the bike is in my name now. I just need some free time! Horrible weather in Iowa this week and a messy house that needs to be clean for weekend company are both hindering me. I'm anxious. Whenever I get a new project I hit it like gangbusters up front and then peter out at about the 80% mark. I like a message board like this that has some visual motivation to keep going.
 

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Discussion Starter · #10 ·
Re: Where she goes, nobody knows. 1971 CB350

Tonight I pulled the carbs off to see what I was up against. Luckily everything looked pretty much as good as I expected it to. The diaphragms are perfectly fine. The only part I need to buy is a float that someone damaged before me as well as it pitting out and leaking. I'll just get a matched pair I guess.

Carburetor #1:

before cleaning


Yes, that gas soaked paper towel smelled as bad as you think it did. In fact, I smell like varnish after a shower.

Scuzzy float bowl. Carb cleaner plus steel scraping with a flathead screwdriver and cleaning with steel wool got it clean.


Crusty needle. I used brasso to bring it back to a smooth and shiny former version of itself.


Top secret method of making needle seats not leak. q-tip in a drill


Ganked float.. Either mother nature did this with frozen water in the bowl or someone very hamfisted was inside these before me. The leak holes are indicated in purple. Both sides had varnished gas in em.


Half way done


Carb #2 is looking about the same. Better actually. And the float is fine.


Nothing eventful to report about carb #2. Here they both are ready to install on my CL350 engine.





If anyone wants to chime in, I have some question about the jets and the needle seat in the float bowl. Are these just press fitted into place? I'm used to stuff screwing into place.
 

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Re: Where she goes, nobody knows. 1971 CB350

You can just solder the holes in the floats and it should work fine. I did that with my Suzuki T500 carbs.
 

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Discussion Starter · #12 ·
Re: Where she goes, nobody knows. 1971 CB350

Yeah, the issue is that there are holes where I showed, but also every bend in the float where it crushed in has a hairline fracture. I just bought a new one on ebay.

I'll still keep hold of the crushed one to see what I can do with it.
 

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Discussion Starter · #13 ·
Re: Where she goes, nobody knows. 1971 CB350

As of now, I have ebayed and/or bought the following items:


-a 1971 CL350 engine with 5500 miles on it
-the gauges from the same CL350 so I have an accurate odometer and a nice looking tach
-a set of somewhat crusty 1971 CB350 exhaust pipes with really clean headers and not so clean mufflers
-the carburetors from the same CL350 which I probably don't need, but nice to have backups
-I got a repro brass float on ebay to replace my damaged one

The plan this weekend is to simply swap out the engines and install my cleaned carburetors and see if I can get it fired up. If so, I'll be insuring it and start riding it around to put it through its paces.

I'm keeping the high bars. All of the cables look horrible, but they are all smooth, so I'm going to ride it like that for now.
 

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Re: Where she goes, nobody knows. 1971 CB350

Nice work so far mate :cool:

Out of curiosity...what year XS650 you building? I LOVE XS650's!
 

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Discussion Starter · #15 ·
Re: Where she goes, nobody knows. 1971 CB350

My XS650 started as a non-titled 77 frame with a 75 engine in it. Right now it's a titled 79 special that I cut the back part off of. I pulled the triple tree off of the other frame, so it's got a 77 front end, 75 engine, 79 frame, and a custom 16" rear wheel of some sort. It's a mess but it has good compression!

So today I spent about three hours cleaning up the carbs from the '72 engine I have. Those stupid tiny gaskets for the jets cost me 5 bucks a piece at a yamaha dealer. My city is unfortunately devoid of motorcycle stores. One of the overflow tubes in these carbs had a hairline crack vertically up the length of it and would leak gas. So I ended up piecing together stuff that works from both sets I have.



Not being able to leave well enough alone, I got bored after supper and went out to 'clean on' my bike. That turned into removing everything necessary to remove the engine. Then I removed the engine. Took a while to figure out how to get it out of the frame with just me there.



When I was messing around I pulled the air boxes for the first time. To my great surprise, the air filters look like some new aftermarket jobs. I ordered foam Unifilter filters already, but I'll probably use these air filters at first before messing with jetting the bike.



A barebones shot of the bike.. I did wind up putting my CL350 engine in the bike, hooking up about 90% of what I unhooked, and calling it a night. It's late.. No more photos ;) There's a new engine in the bike now, so I'm happy. A car jack makes a great positioning tool when mounting up an engine. I had little trouble getting all the bolts back into place.




Tomorrow, fire it up? I'm not sure. There's a vintage Japanese motorcycle rally in Atlantic, Iowa that I'd like to see. I probably won't get there.
 

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Discussion Starter · #16 ·
Re: Where she goes, nobody knows. 1971 CB350

And it starts the first kick. However, it was later found to be running only on one cylinder and it died on me after I rode it around the block and won't start now.

The investigation will continue.

(warning loud)
[youtube:2uz7vfoe]EV0gJAaFCrM[/youtube:2uz7vfoe]


Here's a much quieter video walkaround after I put the ebayed mufflers on it. Still only running on the left cylinder here.

[youtube:2uz7vfoe]DJ0PFjgvTMY[/youtube:2uz7vfoe]
 

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Discussion Starter · #17 ·
Re: My 1971 CB350 project.

I'm not sure what fixed the problem, but my second coil started working after I rode the bike to the gas station to fill up the tires and fuel tank.

I measured the resistance of each coil and got 5.1 ohms on both of them. Then I measured voltage to them when the ignition was turned on and measured exactly 12.26vdc at both of them as well. I pulled the wires from the connectors, sprayed them with contact cleaner and smeared vasoline on them before hooking everything back up again. I also pulled the points cover and pulled emery cloth through the breakers. They're slightly pitted, but they seem to be working. Eventually when the 2nd cylinder kicked in the bike came to life. I'd now put it on par with a 2010 Royal Enfield bullet in terms of power, haha.

I took of picture of the coils. They're blue TEC brand.

http://farm4.static.flickr.com/3380/463 ... 732c_b.jpg

I'm curious if the plug wires are able to unscrew from the coils so I can put some new, more flexible ones in there. I've got the screw in NGK plug caps.

Here it is with both coils firing. I rode it around town tonight for a while to cool off.
[youtube:ym0kzjdf]Msby8kn7UFg[/youtube:ym0kzjdf]
 

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Re: My 1971 CB350 project.

luketrash said:
I'm curious if the plug wires are able to unscrew from the coils so I can put some new, more flexible ones in there. I've got the screw in NGK plug caps.
The plug wire attachment to the coils look like the stock ones and they are not removable for most people.
 

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Discussion Starter · #19 ·
Probably some overlap, but to keep the thread updated with progress:



I've been trying to ride the Honda each night to keep shaking out all of the bugs and issues and to become more familiar with it as a machine.

I was worried because a couple of nights ago after I was riding around with a friend terrorizing the neighborhoods in my city, the bike started to die off at idle. Regardless of how you set the idle stop screws, it'd eventually die off.



The spark plugs looked good, so it wasn't really a misfire, dead cylinder, or other normal things. I measured the compression (somewhat incorrectly) and got 120/90 psi in the cylinders. Bad news I thought.

I put about 20ml of Marvel Mystery Oil down each cylinder and let the bike soak it up overnight. At lunch yesterday out of curiosity I pulled compression cold and got a matching 188psi at each cylinder!



So the oil had cut through the crud on the rings and loosened them up on the piston hopefully. The real test was to be last night after work when I could go ride around for a bit.

I managed to put 25 miles on last night mostly at normal town speeds of about 35-45mph. Enough to get the bike nice and hot. The best part is that it stopped dying off at idle. Hopefully my compression was remaining higher once the bike heated up.

So I got home and pulled the hot compression numbers and was elated to see



A good 168psi in both cylinders. To me it's always a good feeling to have all of the cylinders on my engine within 10% of each other even if they have low compression. I'm happier now than I was a couple of nights ago. The thin oil must have actually done something for a change. (this has never worked in any car I've tried it in, but normally I'm dealing with worn out cars rather than low mileage ones that have sat unused for long periods of time)

After last night's drive, the left cylinder fins were wet with motor oil. So I pulled the plug and tightened the 10mm bolt by it. It turned somewhat easily, so I think it was loose for some reason.



And that wrapped up the night.. The bike might be worthy of riding to work when I find quieter mufflers.

I had a zen motorcycle moment last night on my ride. We have a long straight road that runs along the border of my city, a 45mph road on the outskirts of town. I was cruising at about 30mph listening to the engine, riding into the sunset when I noticed a flock of about 25 Canadian geese flying next to me. So I slowed down to pace them and they flew next to me for over a mile, only about 50 feet away from me. Man, machine, nature.. I'll take it all thanks.
 

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Discussion Starter · #20 ·
I'm happy to report that after 30 miles of riding around the city last night, no oil on the cooling fins anywhere. Tightening those two bolts below the spark plugs has at least temporarily sealed things up. Still having a missing problem on the right and caught my left cylinder plug cap arcing a spark to the valve adjustment cover and/or the clutch cable, what ever it felt like jumping to, so I taped that up. I picked up an old pair of XS650 coils from my buddy on Saturday and plan on experimenting with them if they test as OK.


Yesterday I wet sanded the tank with 400 and then 2000 grit sandpaper. Just for S&G to see what'd happen to the finish. Well, it shined up. Still looks horrible, but from 20 feet, it's shiny and you don't know how horrible it is, ha!



This would work on practically anything that's got paint left on it. My tank was cracked and crazed with chunks of blue paint falling off of the top around the gas inlet.




Doesn't look half bad in motion either. Street lights and the sky reflects off of it now ;)

[youtube:12ixg57f]wvON8pLHEas[/youtube:12ixg57f]
 
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