'72 CB350 cafe "resto-mod"

[luludog]

Thanks guys
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Update (sorry, no pics)
-Decided to fab "outrigger" supports for the swingarm pivot. Right side welded in place, left will be removable so swingarm can to taken off. More on this later.
-Scott has the frame for final welding. Hope to have it back by 1/11/14. Debating to powder coat or paint the frame. It'll be some shade of silver.

In the meantime, need to organize parts & pieces so I can make sense of what I have. Will probably start on the engine next.

[Easter]

Much too nice a project to "just paint" the frame. But then a budget is a budget.

[wingrider]

Much too nice a project to "just paint" the frame. But then a budget is a budget.

I tend to agree with that statement....in the long run seems PC would work better.

[luludog]

Thanks & I'll probably go with PC.

Brief update on the outrigger supports. Left is removable, Right is welded in place. Additional strut bars installed.

[irishcarbomb]

Very nice! This is going to be a nice ride!

[Easter]

Very nice! This is going to a nice ride!

[luludog]

Thanks again Easter

ICB, thanks but my project pales in comparison to your FI/turbo (really nice work, I love the details - Thanks!)

[CBX n GL man]

Just keeps getting better all the time, keep it up. Later.

[luludog]

Thanks

Some updates

Been working on the frame, just about got it ready for powder coat. Refitted the engine shell with countershaft to align & take the offset measurement between the rear & front sprocket. My initial take was about 3/4". I was way off. Ended up at 34mm (about 1 5/16"). Three options. Two of which involved making an offset sprocket. The other was to extend the shaft out 34mm. I went with extending the shaft. Lots of research and homework went into this. Since I'm into cars too; many customs have cut & welded half shafts (drive shafts) successfully. There is some tricky spots, but here's my approach after consulting with Miller Welding, Alloy Metal Treating and multiple web sites.

-Purchased another counter shaft.
-Dropped both shafts off to be annealed
-Cut one shaft to the right length
-Threaded the shafts so they can be held together
-Beveled the edges for welding

I had .002" runout on the stock, original shaft. After welding; its at .003". The shaft is currently getting heat stressed (checks the welding and insures a good starting point for heat treating (60 durameter) finish. Heat treating may also "grow" the shaft, so we'll see how it turns out.

Here's a few shots before welding. I'll post more updates when I get the shaft back.
Oh... some of my friends think this is a science experiment... we'll see







Going with a 525 chain versus the 530 (CBR swingarm sprocket will be kept stock, 525/45T). The 530 is wider than the 525, so had to come up with a way to turn a sprocket down. Ended up using the reminder of the cut off countershaft, welded on the collar for the seal, then trued the inner surface. Drill and tapped the end.



Another shot with the sprocket mounted & machined down on each side.


Made up a seat pan out of 16ga steel. Didn't have a big enough piece, so thought I'd try to join two together. Not real happy how it turned out. Too narrow by about 1/4", and the the seam in the middle was bugging me.


Went to the mill store (they're getting to know me by first name). Bought a piece of 18ga ($5), and formed the bends with a piece of pipe and angle iron resting in the V blocks of the press


Pic of the newer (2nd try) seat pan with the rear CB175 tank section. Still a lot to do to get this to work, but its coming along (shown before upper tubes get cut, which will bring seat/cowl forward about 3 1/2")

[jimmyz3286]

Cool way to get the roll on the edge of you seat pan. It is coming along nicely.

[robin1731]

That should work on the shaft. With this small engine and light weight you are probably ok. On the bikes I do we use the offset sprocket like I mentioned before. And those sprockets have a place for a bearing on the outside. Which then is supported by a plate. The pic I show here is what I mean. Not the best but you can see what I mean, I think. This is in mock-up so there is no sprocket on at the time. But you can see the output shaft. Out from there you can see the support plate with a piece going in toward the output shaft. That piece goes in to the bearing sort of like an axle. That gives the shaft a lot of support. Needed with hard hooking slicks and 200HP or more. The second pic shows the sprocket and the bearing. Just to give a little better idea of what I mean.

[Norbert R]

You're creating magic right there ! So fascinating watching the engineering going into this bike. I really admire your abilities to create such beautiful yet functional solutions for this bike, quite awasome

[luludog]

Thanks guys

Robin. thanks for the info & pics. The offset sprocket/outer bearing was my 2nd option. I did incorporate brackets in the frame... just in case.

[luludog]

More details on the countershaft

-Original shaft was "spark tested" & checked for hardness with a Rockwell Hardness tester. Spark testing is where the metal is literally ground with a grinding wheel (just a touch... or two) and the tech can tell which type of metal its made from. In my case; it verified the info I had research (really close to cold roll steel). The Rockwell hardness was 60.
-Annealing (process of heating the metal hot enough to go beyond the hardness range and letting air cool). Takes the metal back to its original state (or close to it). Its much easier to machine & weld.
-Bought another shaft to use as the extension piece (34mm long). Its was also annealed with the original shaft & sprocket.
-Drilled & tapped shaft (8mm x 1.25), so new piece could be held in place for machining v-groove & welding.
-Once welded; the welded surface was machined down so the bearing & collar could be pressed in place (final assembly after hardening)
-Extended shaft was heat stressed after welding (1100degF). This takes the weld and metal close to the same state.
-Shaft was heat treated, straightened and checked for hardness.

Here's the shaft after the bearing was pressed back on, o-ring installed and seal collar pressed on.


Here it is with the other shaft/gears. Dry fit only. Case still needs to be final cleaned.


Seat/cowl, still needs works...

[robin1731]

That shaft looks pretty good.