Topic: 1972 CB350F First RestoMod

[zammykoo]

Hey guys, Tam here - new to the forums but I've been riding for a few years. I have recently picked up a non-running CB350F and plan to get it back on the road. Looks like it needs a bit of love and I'm here to give it. This is my first project bike so I imagine it being quite a learning curve. But I've been reading plenty of tear down threads on this forum and watching videos which have been super helpful so far. Not very many 350f guides out there but I'm making do with other models.

I'm waiting on some hand tools to arrive so hopefully I can dive in soon. I don't know exactly what I want to do with it yet as far as styling goes - wanted to first check if the engine is in good shape, then go from there. I'll probably start by building a wooden jig to help remove the engine from the frame and prop it up. And as I'm still learning how to rebuild, I'd appreciate any feedback/suggestions/tips along the way.

Cheers!

[zammykoo]

Buy a good quality set of JIS drivers. All the "screws" on that bike are NOT Phillips, they're JIS and they're quite different. Also, an impact hammer to help with stuck or slightly stripped screws makes short order of removal.

Easiest to lay the bike on its right side, then lift the frame off the motor to remove the engine if you go that route. 350s are great little bikes, and plenty of them on this Forum with build/resto threads to help you along. Just scan the "Project" boards for any insight you might need.

Welcome!

Yessir! my JIS screwdrivers and impact are supposed to arrive in the mail today. But Houston has been storming heavily over night and parts of town is flooding. I may not see my package till tomorrow or the next day.

And I know you're right about pulling the engine out by laying it down, but I just can't see myself doing that without the possibility of knackering something up  . I can possibly get a second pair of helping hands but didn't want to rely on that. For now it's a one man show.

[zammykoo]

Today I pulled the engine out! I'm pretty handy with wood working so I put together a mini gantry on casters to make this process a lot easier. It went out really smooth. I didn't have a chance to build a stand/frame to mount the engine to though. I could possibly just buy a HF stand... but what's the fun in that. We'll see what I have time for

[iiAtlas]

Today I pulled the engine out! I'm pretty handy with wood working so I put together a mini gantry on casters to make this process a lot easier. It went out really smooth. I didn't have a chance to build a stand/frame to mount the engine to though. I could possibly just buy a HF stand... but what's the fun in that. We'll see what I have time for

Great job!  That gantry looks sweet - nice project.  Looking forward to whatever is next!

[zammykoo]

Every engine hoist needs a bottle opener! 

It just didn't feel quite complete without one 

[zammykoo]

Great job!  That gantry looks sweet - nice project.  Looking forward to whatever is next!

Thanks! And likewise, I looked through your build thread and you are many steps ahead. Def would be helpful during my tear down

[knowsnothing]

Nice looking hoist.  Might a touch overkill for the 350/400 engines.  I really like working on the smaller 4s because their engines aren't aboslute pigs (ahem 750s) and can be removed solo pretty easily. 

Keep up the good work!

[zammykoo]

Nice looking hoist.  Might a touch overkill for the 350/400 engines.  I really like working on the smaller 4s because their engines aren't aboslute pigs (ahem 750s) and can be removed solo pretty easily. 

Keep up the good work!

You're definitely right! This thing can probably lift 3 of these engines easily. This is my first time pulling an engine however, and doing it solo made me a tad nervous. My wooden anvil stand was made long ago, so it was convenient using it to prop up the other end - while the gantry was cheap & quick to put together. Better safe than sorry!

[zammykoo]

So I'm in a bit of a pickle. I'm trying to remove the camshaft but I can't reach one of the cam sprocket knock bolts with my socket (or open ended wrench). The engine is stuck in that position. I was hoping removing the chain tensioner slippers would give some slack but it is not enough to help rotate the camshaft. Any ideas?

Side question - would there be any reason to save this chain? I have seen suggestions to cut it but I'd hate to ruin a perfectly good chain.

[iiAtlas]

So I'm in a bit of a pickle. I'm trying to remove the camshaft but I can't reach one of the cam sprocket knock bolts with my socket (or open ended wrench). The engine is stuck in that position. I was hoping removing the chain tensioner slippers would give some slack but it is not enough to help rotate the camshaft. Any ideas?

Side question - would there be any reason to save this chain? I have seen suggestions to cut it but I'd hate to ruin a perfectly good chain.

You're picture won't load but that could just be me.  If the bolt is what I'm thinking of, you'll just need to rotate that sprocket along the chain so that the bolt comes up in to position.  From what I remember it was a bit of an angles game, but any standard socket should be able to grab it.

Sorry if this is not the bolt you're talking about...hard to guess without the picture!  I used a coat hanger and rubberband to hold the cam chain once I got it off.  Here's a link to that post in my thread!

[zammykoo]

You're picture won't load but that could just be me.  If the bolt is what I'm thinking of, you'll just need to rotate that sprocket along the chain so that the bolt comes up in to position.  From what I remember it was a bit of an angles game, but any standard socket should be able to grab it.

Sorry if this is not the bolt you're talking about...hard to guess without the picture!  I used a coat hanger and rubberband to hold the cam chain once I got it off.  Here's a link to that post in my thread!

Hmm, I'm not sure why the photo isn't showing up. I'm using Google Photos to host my images for the first time, maybe it's not the best way to. But I'll upload here.

And thanks for the feedback, but the engine does not rotate freely for me to do so. I suppose one of the pistons are stuck. I tried soaking in marvel mystery oil for many months but still doesn't budge.

I'll try to keep at loosening the chain somehow. Maybe there's something else I can undo/unbolt other than the tensioner slippers? Other than that, I do have a bicycle chain breaker that I can try haha.

[iiAtlas]

You're picture won't load but that could just be me.  If the bolt is what I'm thinking of, you'll just need to rotate that sprocket along the chain so that the bolt comes up in to position.  From what I remember it was a bit of an angles game, but any standard socket should be able to grab it.

Sorry if this is not the bolt you're talking about...hard to guess without the picture!  I used a coat hanger and rubberband to hold the cam chain once I got it off.  Here's a link to that post in my thread!

Ahh, got it.  Shame!  Maybe someone here wiser than I can chime in...interested in seeing what they recommend.

[zammykoo]

Well I tried everything I can think of to save the chain but ended up cutting it to release the camshaft. I tried rocking the cam back and fourth given the extra slack from removing the tensioner slippers, but was still not enough for me to skip a tooth one at a time.

So then I bought a set of HF offset wrenches but the space was still too tight for the wrench head to squeeze into. I figured at this point I'd say screw it... and took a hack saw and carefully worked my way through, making sure the blade did not touch any of the sprocket teeth. A couple mins of sawing for each side of the chain link was enough to free it.



Cylinder head came out quite easily after. The pistons looks really dirty but I hope it will clean up ok. It appears that piston #3 is stuck. I tried taking the cylinder housing off by wiggling a bit and pulling, and started sliding off. Didn't put much too pressure anywhere but it's def stuck. I might take a torch to it next.





On another note, I got an ultrasonic cleaner in hopes to ease the carb cleaning process. I've seen many mixed reviews but want to try it for myself. So far I tested and am getting pretty decent results. I used about 4:1 water to SG mix at 3 cycles of 450 seconds with heat. I think it may be too diluted of a mixture so I will make more concentrated next, or pre-soak. So many different combinations to try!

[zammykoo]

There is a broken spark plug that has been troubling me. I tried using an extractor but it won't budge. I cleared out all of the porcelain innards so am able to see all the way through. I tried lubricating it and also applying some heat but no movement. I'm afraid to apply too much force on the extractor, maybe causing damage to the threads. Not sure if it would be ok to keep going. Any thoughts?

[Stev-o]

Put some more penetrating fluid on it for a day or two.  ATF/acetone makes a great cocktail. 

Then heat the head to expand it and unscrew the extractor.

[zammykoo]

Put some more penetrating fluid on it for a day or two.  ATF/acetone makes a great cocktail. 

Then heat the head to expand it and unscrew the extractor.

Ah, I've seen many mentions of that mix for piston rings but never crossed my mind to try that on the spark plugs! Thanks Stev-o

[zammykoo]

So the piston and broken spark plug has been soaking in the ATF/Acetone mix for almost a day now. I'll see if there is any movement when I get out of the office today.

In the mean time I got my hands on some hid projectors that I'm considering for this project. Definitely not what you'd call classic style, but I'm digging it. It may completely change what I had in mind for styling.



I also rebuilt this old junked compressor that was given to me. She works as good as new now! I'm hoping to use it for some light duty soda blasting. Time to whip together a DIY blast cabinet

[SOHC4 Cafe Racer Fan]

If the rest of the bike is period correct, I'd save the HID projectors for another project -- maybe a restomod.

[zammykoo]

You need to pay close attention to the Wattage of those projectors. They may tax your charging/electrical system very heavily and leave you dark and dead beside the road. Your stock headlight was probably 35/45 Lo to Hi. Just something to think about...

Thanks for the wise words. I was looking into that as well. I have a 35w ballast kit, so maybe having a single projector would be more appropriate than a dual setup. Or maybe it's still ok if converting the tail lamp to leds? Still need to do some more digging!

[sbeckman7]

Good to see another 350F project! Welcome to the forum, looking forward to seeing where this goes.

[zammykoo]

I doubt the tail light conversion would release sufficient taxing to satisfy a second HID. This dual lamp conversion is something I've explored for a build but shied away from for this very reason. Absent of a major upgrade to the alternator or using an aftermarket stator designed for battery-less operation (with CDI) you'll likely not get there.

Any chance you could find/use 1 HID and a single LED projector instead. That may get you there. And lastly, in some states, those won't pass Inspection because they don't have the focus planes or dimmers as HI/LO operation. Depends upon where you live, and how sticky the Inspectors/Cops are. If the lens doesn't have DOT approved on it, ticket time for you!

True that. The more I think about it I may end up going with a single projector setup and retrofit that into a headlamp bucket (has high beam solenoid). And this could be a phase two thing once I get the bike running.

Good to see another 350F project! Welcome to the forum, looking forward to seeing where this goes.

Likewise, I have been enjoying watching your build progress! But hey, I noticed your little commotion about the scratched cylinder, I hope that all works out. I have been meaning to get around to cleaning mine to further inspect, but so far they look ok.

[zammykoo]

So it took much longer than I wanted the this darn cylinder block is finally off! Piston #3 was stuck in there good and did not give up without a fight.

I removed all pistons and proceeded to clean 'em up. First tried ultrasonic/SG first, then the chem-dip. I started seeing good results after the chem-dip, so I'm not sure if the ultrasonic/SG bath helped much. I plan on putting together a makeshift blast cabinet so I can do some soda blasting as well. Rings are still seized to piston #3, not sure if I can get them off. I'll try applying some heat and see how that goes.

The cylinders look pretty smooth with no obvious scores/scratches. I need to clean it up a bit more and remove carbon to fully inspect, but looks ok so far.

Bonus question: These pistons have one-piece oil rings. Can three-piece rings be used interchangeably?

[sbeckman7]

Looks like you're making good progress.  How is that ultrasonic cleaner treating you?  I ended up returning mine after trying a few parts with it, as it was good but not great.

I ended up saving my scored cylinders thankfully.  It sounds like you're also planning on installing new rings?  I would highly recommend it after what happened to me!

[zammykoo]

Looks like you're making good progress.  How is that ultrasonic cleaner treating you?  I ended up returning mine after trying a few parts with it, as it was good but not great.

I ended up saving my scored cylinders thankfully.  It sounds like you're also planning on installing new rings?  I would highly recommend it after what happened to me!

I'm experiencing the same with my ultrasonic cleaner. I think it has its place as a cleaning machine but it doesn't seem to be meant for engine parts - at least not this model. I bet it works well on jewelry, etc.

And yes, I'm planning to get new rings too but I need to know if the three piece oil rings are interchangeable with this first.

[Hurstman1972]

Hmmm. I rebuilt mine with one piece oil rings that seem to be working OK, although I'd druther have the 3 pc style. If you know of a source, pass it along! Thx!