Topic: '82 cb650sc cafe project

[kerryb]

Well thats a color of a different horse!  I sent a reply to Nils indicating my confusion.  We'll have to wait and see what he says. 
The picture he linked me to showed eye to eye, hopefully just a typo, or my poor eye skills.
In other news, hows this?  Started a headlight/name badge mount.

[kerryb]

Another email to Nils and we have settled on the Ikon cbx shocks.  that means we need shock mounts...so here goes, I think I have it figured out.  You can't buy these at dime city, but I can steal their idea!  I guess the real trick will be making the other side match!

[kerryb]

So I got the welding done and the shocks mounted.  Looks like I need to get the engine back in and a rider on it to see where it sits.  I may be able to stick with stock shock length after all.
Also practicing my sewing in preparation for a seat cover!

[Hutch]

Your frame modification looks great.  What tank are you using?  I was able to mount a tank from a '81 CB650 custom by relocating the front tank mounts.  It will also allow you eliminate the vacuum assisted petcock.  The only thing to look out for is the petcock clearing the motor.  I barely made it...

[Hutch]

Don't know what your pan is for the air box with the frame changes.  I made an adapter to fit a large pod filter.  I kept the stock cv carbs, this set up works fine since I didn't attempt to eliminate the plenum.  This allowed me space to relocate the battery, I mounted the rectifier to the bottom of the seat pan.

[kerryb]

Your frame modification looks great.  What tank are you using?  I was able to mount a tank from a '81 CB650 custom by relocating the front tank mounts.  It will also allow you eliminate the vacuum assisted petcock.  The only thing to look out for is the petcock clearing the motor.  I barely made it...

I'm using a '78 CB750k tank with slight mods to the frame mounts.  The petcock clears ok with the CV carbs or the pd42a's from the same '78k.  wish I could find a petcock with a rear outlet or just run the hose around the rear of carb #1.  Not sure which set of carbs will be final as the 42's will require a new rack and linkage to work, but there is plenty of room to make a new custom airbox. 
The last item without a plan yet is the battery.  Either mount the stock battery somewhere in the rear triangle or research a super small one that is still capable of running the starter motor because there is no kickstart, but plenty of room under/in the seat and cowl.

[Hutch]

Your frame modification looks great.  What tank are you using?  I was able to mount a tank from a '81 CB650 custom by relocating the front tank mounts.  It will also allow you eliminate the vacuum assisted petcock.  The only thing to look out for is the petcock clearing the motor.  I barely made it...

I'm using a '78 CB750k tank with slight mods to the frame mounts.  The petcock clears ok with the CV carbs or the pd42a's from the same '78k.  wish I could find a petcock with a rear outlet or just run the hose around the rear of carb #1.  Not sure which set of carbs will be final as the 42's will require a new rack and linkage to work, but there is plenty of room to make a new custom airbox. 
The last item without a plan yet is the battery.  Either mount the stock battery somewhere in the rear triangle or research a super small one that is still capable of running the starter motor because there is no kickstart, but plenty of room under/in the seat and cowl.

My '81 petcock has a rear outlet, not sure of the thread size.  There's always pingel, but they are $$$.  A small battery tucked under the seat would be ideal IMO.  I went with a Shorai lithium which is damn near the same size as the stock battery since I didn't have any more room under the seat.

Honestly, the stock CV carbs where not the nightmare I thought they'd be.  Although the air mixture screws on carbs 2 & 3 are a pain in the ass to adjust once the carbs are on.

Following your progress intently.  Your work on the frame has me considering going full on cafe style with the same frame mod, but then I might have to figure out how to replace the stock comstars with a set of 18" spoke wheels  .

[Hutch]

Not to sidetrack the rear suspension and carb discussion, but what are your plans for handlebars since the SC has through bars.  I wound up shaving the excess material off of the top yoke and mounting clip-ons.  Top mount bars would have been ideal, but I didn't think it was worth the expense of ordering a custom made yoke since I was keeping things simple.  I also considered riser bushings, like some Harleys, but I need a new home for the ignition switch which I mounted in one of the holes using a set screw.

[kerryb]

The handlebars we have now were cut from a pair of old apes in my stash.  They had just the right bend between the riser and the grip.  They have about 4" of height adjustment, and in the current location, place the grips approx where superbike bars would be.  Gauges are white-faced from another cb750 (80's) and the ignition will probably remain in the stock position.  Current plans are to put a bank of idiot leds on the triple and one big red led in the steering tube opening.  The most significant change planned is the new headlight (smaller) which will have no wiring in it except the two wires to power the light.  These changes can be seen in earlier posts on this thread.

[kerryb]

I couldn't start the seat pan until the tank mount was finished, can't believe how long that took me.  With all the overthinkin' I'm wondering if I missed something.  This is my first tank engineering job.  So take a look and see if there are any details I missed or should change before final welding takes place...please.
Mounting pegs in front were dropped and shortened to accept the '78 cb750k tank.
Rear mounting plate created to hold the rubber feet and provide a rubber cushion to clamp against.
current clamp is a strip of aluminum bar into an existing threaded boss.  I think a more substantial clamp will be made for greater purchase on the tank.

p.s.  If some fool in the future decides to stand on the seat and tank, I don't want the tank coming loose!

[kerryb]

The plate is mild steel, about 3/32", but tank is not bolted to the plate. 
Haven't decided yet to weld the plate on or just use the bolts.  So a clamp is still needed.

[kerryb]

Thanks for the input calj737,  time to move on to electrical component placement so I can figure out the seatpan and space needs under the seat.  I would rather not put the weight of the battery in the seat hump, just seems wrong on a weight distribution principle.  Other suggestions welcome...   

[kerryb]

The battery will be a compromise with a nice battery box mounted just above or on the swingarm.  Maybe even have the starter solenoid hung off the side like a reservoir on a shock.
So I tacked on a cross brace between the shock mounts and made a tray to play with electrical placement.  What I've discovered is there is enough room for the igniters under the tank.  The fuse box can be much smaller with blade fuses.  Which brings us to the voltage regulator.  A) Are the rubber isolation mounts imperative or just a good idea?  B) Does the Volt reg generate enough heat to warrant mounting it under the tray in the airstream, or is placing it in the semi-protected tray under the seat ok?

[kerryb]

Had this idea for mounting the seat rolling around in my head but couldn't decide how to carry it out.  rummaging through the scrap box and came across the original frame brace cut from the bike earlier.  looked a little closer and found some tubing with the right ID. for the "feet" to sit on the frame rails.  the feet will be lined with neoprene rubber, and the brace will be glassed into the seat pan.  resulting cavity underneath should allow plenty of room in the electrics tray....progress.

[kerryb]

It's probably overkill, but hey what do I know, it's my first one!  Finished up the backbone for the café seat.  Added a plastic bumper tab for the original seat mount pocket, a "spine" to keep the front in line during glasswork, and a rear cross brace with two mounting studs that fit the frame.  Couple of wingnuts with lock washers should be all I need to hold the seat on and still be able to remove it without tools.

[kerryb]

Took some time out to see if my HF tig welder would actually work.  Actually I wanted to see if I could make more than scrap!  I'm pretty good at turning perfectly good metal into scrap.  What I found out is it's true...without a foot pedal, success is very difficult.  So I had to take some time to add a pedal to see if it would help.  Great news, the pedal works fine once you get your heat range dialed in.  Just not ready to commit my skills to the bike frame yet!

[kerryb]

Back at this after a long distraction, I think I have the airbox solution I was after.  Working on the form for the fiberglass "snorkle".

[Alan F.]

I do like your foot pedal, sometimes things are still just that simple and functional.

[kerryb]

Dusting this off in an attempt to finish it.  Enough paint is done to begin reassembly.

[Godffery]

Hey good to see you're back at it.

[kerryb]

Put the engine back in using the hook method, learned here many years ago...thanks.  I hate new paint!  Maybe I'll just let the scratches occur and call it a survivor instead of a new abomination...yeah, that would lower the stress a lot!

[willbird]

Nice work.

Bill

[kerryb]

Thanks Bill.


I wanted to keep the stock battery for budget considerations, so here's the new battery box.
Most logical place for the solenoid was on the battery box.

[kerryb]

I'm starting to understand why people like motogadget so much.  This harness works great, but hiding it is going to be another matter.

[kerryb]

With just a few re-wraps, the harness is on and hiding nicely.