Topic: 1972 CB350 For the Daughter

[Harsh]

So I am stuck.  I have a hoop I cut out of a CL350 that should work for my purposes.  The thickness of the frame 3/4" and the diameter of the hoop is also 3/4" which should make for a nice looking end of the frame once everything is welded together.  The hoop is a fair bit wider than the seat and frame though.  So I cut it in half and will weld it back together once I get the angles and width correct.  However, the underside of the seat has these humps that jut out just above the frame preventing the hoops from being able to go up without bending or pinching them to go around the hump.  Either of which might defeat the purpose of the hoop.  I would probably end up having to make some sort of an "S" bend.  Where I am really stuck is that I need to cut the frame to figure out where I need to place the hoop and make the bends.  Mocking up the hoop on either the inside or the outside of the frame won't provide a true representation of where I need bends/cuts. So I feel I am basically going to have to say the hell with it and take a chance at cutting the frame and hopefully it will work out.

[grcamna2]

You might also use a piece of similar dia. copper tubing(it bends easy w/ a plumber's pipe bender)to mock-it-up.

[Harsh]

You might also use a piece of similar dia. copper tubing(it bends easy w/ a plumber's pipe bender)to mock-it-up.

Bill, that is a fantastic idea and I think I have the stuff in the garage already.

[grcamna2]

You might also use a piece of similar dia. copper tubing(it bends easy w/ a plumber's pipe bender)to mock-it-up.

Bill, that is a fantastic idea and I think I have the stuff in the garage already.

The last part would be if you could also bend the steel hoop in a similar way to match the mock-up..

[Harsh]

The copper didn't end up working.  I couldn't get the bend tight enough before it would snap.  So I used a piece of very thing all thread I had laying around.  Bent it to the outside shape I needed and fit the two loop halves together on the inside radius.  Cut the angle I needed on one piece of the hoop and tacked them together.  It seems to fit, but the only way to truly tell is to cut the frame and slide it into place.  I think I am going to cut on line that followed the seat seam and tack in the hoop.

[Restoration Fan]

Looks pretty good.  Next time, if you're trying to bend it, fill the pipe with sand and apply heat.  When it's cherry red, do a slight bend over something with a similar radius.  If you do the bends in a couple of gradual bends and have the pipe hot enough, the sand should keep it from splitting.

[Harsh]

Struggled all weekend with the hoop.  So the hoop is gone.  No matter what I do I just can't get it to fit under the seat.  I decided to try the stock piece I cut off and it fits pretty darn good and the seat fits over it.  Not exactly what I wanted to do to the end of the frame, but it will work.  I braced the stock hoop to the frame with some 3/16" flat stock.

Finished tack welding everything thing in place this evening and a buddy of mine is going to do the finish welding for me tomorrow.  The bit of fender that sticks out under the seat will be cut off to match the shape of the seat.

[grcamna2]

That orig. top/rear frame 'bridge' will work for many different functions 

[RAFster122s]

With a bit of work could you reshape the curve below the shock mount by reducing the radius to sweep it up from the diagonal tube towards the seat's line.
Maybe round the area around the shock mount in a curved bulge.
it doesn't need it but it would be an asthetic change.
Just a spitball idea.

[Harsh]

Re-shaping that was already in the plans.  It just wasn't necessary to do right now in order to get everything ready to be welded.

[Harsh]

Got everything welded up yesterday and spent the morning cleaning up the welds.






Filled in the holes left from some spot welded pieces that I cut off.


Still need to go back and fill in the dimples from drilling out some spot welds.



With the fender installed.  You can see a tiny bit of it under the seat, but that is because the picture was taken at a lower angle and kind of looking up under the seat.

[grcamna2]

I think it looks good where you filled-in the open frame on either  side below the seat.

[Harsh]

I guess it is time to do a little catch up update.

I cut down the front fender, although I think I may have cut it a bit shorter than I wanted to.  It looked good mocked up with tape for the cut lines, but after it was done I think it is a tad too short.  Oh well...too late now.

Scrubbed down the engine over the weekend.  Getting the bead blasting media out of the passages, nooks, and crannies is always non fun, but obviously has to be done.  When I was done there was enough media in the bottom of the basin to fill my cupped palm.

Proceeded on to blocking the head and jugs.  The head has a fair amount of casting flaws, but it should seal fine.  I also honed the cylinders and lapped the valves.  My buddy is supposed to bring my tap and die set back tonight so I will be able to drill and tap the holes for the oil splash guard plate.  I am starting to get excited about getting the engine back together.  I just hope there is a semi warm day in the near future so I can get it painted.

[grcamna2]

Looks good Harsh,did you use a medium grit ball hone ?

[Harsh]

I honestly don't remember what grit the ball hone is.  It is the same one I used on the other 350 and the 750.

[SOHC4 Cafe Racer Fan]

Nice job.  How did you clean the passages?

[Harsh]

Soapy water, bore brushes, and some pipe brushes.  I spent two days cleaning everything.   It sucked, but I am satisfied they are free of any media.

[SOHC4 Cafe Racer Fan]

Soapy water, bore brushes, and some pipe brushes.  I spent two days cleaning everything.   It sucked, but I am satisfied they are free of any media.

Damn. I wasn't sure if it was something you could accomplish with compressed air or whether you needed to force a pipe brush though.  That's an entire different kettle of fish.

[Harsh]

I would rather be overly thorough than leave some blasting media and have it tear up the internals of the engine.

[RAFster122s]

Yeah, better to spend money once on a rebuild rather than doing it twice. Too costly in time and money to do twice.  At least we are not paying Ducati parts prices, but we don't have Ducati handling or performance either...

It is looking good Harsh!  How's the daughter's deployment?

David

[Harsh]

True and thanks.

She has been back for a few months now.  Her ship is currently in the yards getting some upgrades and repairs done.  They have her working in an industrial facility while they are in the yards.  She does a lot of heavy duty media blasting and powder coating.  So it looks like we will be able to save some money getting parts powder coated.  We will buy the powder, which is relatively cheap, and she can spray it at work.

[RAFster122s]

I am sure you have already thought to chase the threaded holes to ensure no media is hiding in them to prevent any broken bolts or screws.  Never hurts to run a good bottoming tap in the holes.

Glad she is staying busy and enjoying the time home..being bored is no fun.

Nils must do an enormous amount of masking to keep media out of his vaporblasting of engine components or he goes through a lot of brushes...
David

[Harsh]

Spent the last two days cleaning the engine parts with acetone and getting them taped up for painting.  I also drilled and tapped the holes for the oil splash guard.  Tomorrow should be just a quick acetone wipe down then on to the painting.  Tomorrow is probably going to be the last good temperature day for the year so I have to get it done tomorrow.

[RAFster122s]

Hope the paintwork goes well with no runs or drips to deal with...

[palepainter]

As a painter, I will say, it is all in the prep.  Looks like you are going to have one nicely detailed motor.  Looking forward to following along.