Topic: Pin2Hot's 73 CB750

[Pin2Hot]

That Ruckus has a 2-bolt bicycle stem.  LOL 

Ha yes it does!  It's held up incredibly well.  I mean, as manly as one can be riding a Ruckus, the stock handlebars forced you to look like a total nerd.  So the pegs and lowered bars were the solution.  Now I only look like half a nerd cruising around at 32 mph.

I can certainly see the light at the end of the tunnel on the big bike.  I think getting the parts blasted and primed will be a shot in the arm to take it across the line.

[Pin2Hot]

Hey some work on the actual project!  I spent the past few nights making a pattern for the seat pan.  I had never really intended to use a full seat pan for this bike but instead use a few struts that stretched across the frame hoop to mount the mUnit, reg/rec and the seat itself.  Using a seat pan has made it easier to keep the seat itself nice and centered within the frame rails AND prevents any water from splashing up on my butt.  It also will probably look much nicer.

Holding it in place:


It's 16 gauge steel so I was able to bend it into position pretty easily.  With the help of some duct tape of course:


Failed tack and crappy braze tacks.  I tacked with silicon bronze because it's easier but will come back and stitch it into place with regular 70S.


Welding in sandals.  Ended up looking pretty straight!


I'll weld it out tonight, put the turn signal tabs back on and then I think I can call the frame complete.  Pretty neat.

[Pin2Hot]

Quick update: seat pan secured in place and the seat itself is being fitted.  The plan is to sandwich these two pieces of flexible plywood with some walnut veneer to make it look purty.  On top of that will sit a 1/4" plywood base with a 5/8" gel seat.  The shape is roughly shown by the blue sharpie marks on the top of the seat.  I'm planning on gluing it up this week.  Still have to re-weld the signal tabs back on.

Bronze caterpillars:


Top:


Bendy:


Profile:

[Pin2Hot]

I came across something interesting in my nightly YouTubing:

Take a look at the second photo thrown down in the video, looks familiar...

I think it's safe to say that the maker of this kit cruises this thread (hello!).  Anyone use this kit?  Seems pretty slick and well made.  It definitely solves the problem of relocating the oil tank and looks good, keeps things nice and low. 

[algophobe]

aw man, I coulda used it for my project. I really haven't looked into it but where does the cb550 place its oil reserve? I've seen cb550 builds and oil tanks are nowhere to be found.

btw. nice work on the bike so far. I welded my tray onto the frame itself as well. but some have advised that it would have been better to weld mounting tabs and attach the trays that way. not sure of what the pros here inputs on that.

[Pin2Hot]

I'm not very familiar with the 550 but I would imagine the oil is stored in the bottom of the engine for a wet sump set up.  Cal or Durango know that bike better.

Yeah the seat pan for me doesn't serve much purpose to be removable.  The seat itself will be detachable from the pan as well as the reg/rec and mUnit.  So it's more of a mounting point for other things.  It's all about what works for you.

Speaking of the seat, I spent a very frustrating weekend working on it.  I made progress on the top, cushy part of the seat but have stalled on sewing the suede.  SonofaB is it hard to work with.  I like to consider myself a decent seamstress but trying to pin Alcantara and gettin it to curve is a huge pain.  I gave up yesterday and tried to mow the lawn, only to have the lawn motor and weed eater fail to start.  So I bought some bourbon and grilled shishkabobs instead.

Here's a sample of what the seat will look like in the end.  My dad had some gorgeous walnut veneer that I'm going to glue to the bent plywood seat base and the cushy seat will be screwed to that.  This is a sample of the stitching on the micro-suede set on top of the walnut:


Cutting the gel to fit the pattern, complete with Good Housekeeping: required for all things sewing related.  I rubbed some corn starch on the gel to prevent it from sticking because it sticks to EVERYTHING.  I found cutting it was easiest with a big chef's knife:


The 1/4" plywood base for the cushy part of the seat with the gel:


Layup of the layers that make up the cushy part of the seat:


The actual seat top, already top-stitched.  This is what was giving so much trouble yesterday; trying to attach the 1 1/2" strip to the curved edge to make up the sides of the cusion.

[algophobe]

Beautiful work with the seat so far. I like how you are not afraid to tackle on different materials and elements of the build yourself. Growing up my mom was a seamstress, and she would bring home Stacks and stacks of material to sew and I would pack them up throw it in the van and turn it back in to the manufacturer. During Summers I used to help her sew to earn some spending money. And it's strange how satisfying that all the skills with working with different materials over a life time can converge in a bike build.

[Pin2Hot]

Beautiful work with the seat so far. I like how you are not afraid to tackle on different materials and elements of the build yourself. Growing up my mom was a seamstress, and she would bring home Stacks and stacks of material to sew and I would pack them up throw it in the van and turn it back in to the manufacturer. During Summers I used to help her sew to earn some spending money. And it's strange how satisfying that all the skills with working with different materials over a life time can converge in a bike build.

That's great!  My grandmother sewed all of her own clothes and my mother taught me how to use our sewing machine when I was a kid.  I always found it very satisfying.  I made this big stuffed camel in 7th grade for home economics and I remember how I couldn't wait to get to the class to finish it up.  I also attempted a pair of jeans recently that kind of sort of worked out . . . I actually wanted to work some of the denim into the bike somewhere but I decided against it.  My grandmother passed on her sewing machine to me so it's serving a new life making things instead of collecting dust in a closet.

There's something tangible about sewing that power tools and welders don't provide.  Maybe it's the up close, directly-in-your-hands requirement of sewing that makes it satisfying.  I couldn't agree more how skills can converge, great way to put it.  Thanks for the kind words.

[Pin2Hot]

I'm getting close to sending things off for paint / powder coat so I'm spending a lot of time fixing tiny holes and filling in some of my poorer welds.  I found that brazing in some silicon bronze has been filling things in nicely even though it means a bit more elbow grease is required to get things smooth.  I've chosen to fill holes with metal as I'm going to powder coat the frame and swingarm.  I asked some local powder coat shops and they said I could use JB Weld to fill things in but I ran risk of it popping and blowing out the work.  So, now I get to spend a ton of time filing down more shtty welds in an effort to hide the previous shttier welds.  Hey, whatever it takes I guess.

Testing out my plan:


Looking a lot better after filing:


Added some more bronze, now it's time to file and I'll finish up with emery cloth to smooth it all out.  Makes me really wish I had a pipe sander / polisher.


I also sewed the toughest part of the seat, really happy with out how turned out!


Top stitch:

[DurangoCB]

If there were a Like button, I would hit it.  Since I don't have much to say and so many threads in the Project subforum are met with crickets. 

Looks awesome and learning new skills is so great. 

[Pin2Hot]

Oh hey!  I spent the holiday weekend filling in welds and shaping things with a file.  My arms are dead but as I type this, the frame, swing arm and other parts are in the car waiting to be chauffeured out to the powder coater.   The frame will be a cement gray (think Toyota Tacoma / Scion TC), the swing arm and other bits will be black.  By the end of the week (or whenever the guy gets finished) I should have some pretty sexy looking things back in the garage.  Then it's time to clean EVERYTHING, re-assemble and wire this thing up.  I've said it before but I've been really looking forward to wiring this bike for a while.  I've got some interesting ideas that I think should look pretty slick.

Brazed and shaped:


Closeup:


Oh yeah, I also made a license plate bracket:


Items to be coated: frame, swing arm, steering stem / triple tree, engine mounts, brake stay, battery box:


I'll report back as soon as things are colorful.

[Pin2Hot]

Annnnd we're back.

Powder coat looks incredible and the color is exactly what I was looking for.  I've definitely learned a few lessons in terms of making sure things are absolutely perfect before getting something coated but I'm completely happy with the results.

Petting my new puppy.


Swing arm and frame w/ battery box.


Frame closeup:


Swingarm closeup:


License plate bracket with new LED plate light:


Temporary assembly to see how it looks and determine final tail light placement.  Turns out, where I wanted to place the taillight (hanging it off the tail) made it look like the rider had a tail light nutsack sooooo I'm moving it to above the license plate mount just above the plate light:


My brother demonstrating the riding position.  I like the somewhat aggressive stance, not too rear set.  Although it does make me want to make an extra set of rear set mounts to play around with foot peg position.  But I'll keep what I've got for now:


I've started to mount the mUnit and other electrical gadgetry so the final assembly phase begins now.  However, my time in the garage over the next few months is going to be very limited, hopefully I'll find time to finish this up before things get cold again . . .

[andy750]

Subscribed! Love the detailed photos and the one of the riding position nails it. Great work thanks for sharing.

[DurangoCB]

Looking really good.  I am really liking any frame color that isn't black right now.  And I'm sure my tastes will swing back to not liking anything non-black at some point LOL  The tail lights/brackets are a nice, simple solution.  Works with that subframe nicely! 

I'm shooting for August 1st completion date.  I'll race ya!

[Pin2Hot]

I've been working on the seat and mounting things as quickly as possible while I have time.  Here's some progress.

My seat consists of two parts: the seat pan, which is two pieces of bendy plywood laminated together and the cushion which is another piece of stiff plywood with gel and closed cell foam.  The cushion will be covered with some suede and stitched up all purty.  The seat pan will also get a walnut veneer once I've created all the mounting holes and what not.

Laminating the seat pan (you can never have too many clamps):


One thing thing I realized after I popped the pan out, the metal pan below buckled quite a bit during the powdercoat process and those buckles transferred to the wooden pan.  It's not a huge deal but I'd definitely do this differently next time:


Underside of the pan, showing the threaded inserts I'll be using to attach the pan to the metal of the frame below:


Mounting holes:


Cushion.  It won't sit this high as some of the fabric will be tucked under to make sure it's nice and taught around the stiff plywood base.  Still trying to solve exactly how this will be attached to the pan but I have a few ideas.


More or less the final position of the cushion:


Underside of the cushion for those who are curious.  I wanted to hide the small area where the original battery box mounted so the cushion has a small extension on it.  That's why there's a section that's "enclosed".


Pretty happy with the look, I think it'll really pop once the walnut veneer is laminated.  Stay tuned!

[Pin2Hot]

I got the cushion all finished up and I'm pretty happy with the results.  I need to do a bit of tucking to get it looking all nice and neat.  I'll do that once I get the veneer laminated on.  For the most part, that's the entire seat.  Kinda nice to finally see and feel it's true shape.  It's about as comfortable as a supermoto or a dirt bike.  Overall I'm pretty happy with it.

Cushion:


Pretty good length, covers up some holes:


Underside for the curious.  This is prior to me stapling things down.  There are 3 stainless steel button head screws I glued into the cushion board.  I have some nylon nuts under the seat pan that will grab them and secure it to the pan:


I also decided to place my taillight in this position instead of hanging off the bottom of the seat.  I think it looks much better down here:


Hope to have the engine back in this weekend and the seat 100% finished up.

[DurangoCB]

Crap, I forgot we were racing.  I better take the day off work and get busy. 

[Pin2Hot]

Hey.  I'm not dead.  Had my first kid so the bike has taken a backseat for the foreseeable future.  However, in the 2 seconds a day I get to myself, I've been working on the harness.  I'm using 16 ga stranded for most everything and covering each conductor in paracord to make it all purty.  Here are a few examples:

Power/ground to the PCB:


An unfinished to/from mUnit connector:




Here's an updated drawing of what I'm using to keep track of things:


Kids are fun . . . already thinking of what his first bike is going to be.  CRF50F?

[Ilja]

First, please enjoy the wonderful sunset we witnessed in mid-MO/IL this wonderful Memorial Day weekend.  We spent all weekend (and the previous weekend) building that dock cover.  It was a LOT of work and my back and legs are killing me today but it was worth it:



Second, enjoy the beeeeeautiful stainless steel exhaust that arrived from our friends up North, Ripple Rock.  The copper collar things are only temporary as I got studs that were WAY too long. 


The mid-pipe is going to get modified to shorten it up and angle it up/out.  That'll let me attach a hanger point on the muffler to support the rear of the exhaust from the rearset mount.


I'm going to miss my deadline of getting this done in time to go to Tulsa, OK next weekend but work will continue.  I hate having to keep moving my deadline but that's the way it goes sometime.  I'll keep at it.

Congrats on your kid! Hopefully you have a balanced work/private life so you can enjoy both the family and the bikes. 

Awesome project, so many big modifications.... I especially like that you just made a PCB for electrical connections and also that fuel tank is really nice.

Can I ask what outside diameter those stainless header pipes have? Looks good... is it 38mm ? 

[Pin2Hot]

Congrats on your kid! Hopefully you have a balanced work/private life so you can enjoy both the family and the bikes. 

Awesome project, so many big modifications.... I especially like that you just made a PCB for electrical connections and also that fuel tank is really nice.

Can I ask what outside diameter those stainless header pipes have? Looks good... is it 38mm ? 

Thanks Ilja.  The baby has certainly put things on hold but this project WILL be completed, just don't know when.

The pipes are 38mm.


I realize this is a digital set of calipers but the battery is dead. 

[Pin2Hot]

Geez, it's been a while.  This project has languished for years so a little 7 month dormant period ain't nothin!  I recently moved (for hopefully the last time) and have gotten everything back out and begun re-assembly.  Priorities now are wiring things up which I plan to document heavily, maybe even shoot some videos and create a little series about wiring it up from scratch.

Assembly:


I have to thread a rod to create a custom lower engine hanger as the stock hanger is bent and I'm no longer using the stock footpegs which makes the stock one far too long.  You can see the unthreaded rod at the base of the rear-set mount:


Making sure I find center to mount the m-Unit:



Question - BOLT, HEX. (8X40) 93101-08040-0B - Can anyone confirm that this is indeed an M8 - 1.25 pitch bolt?  I'm having trouble threading these into the upper triple tree and I'd like to run a tap through them to clean up the threads as it's possible some powder coat got stuck in there.  Just need to confirm I'm not crazy before destroying the threads in this part . . .

Maybe it'll get done this summer? 

[Pin2Hot]

8x40 is 1.25 pitch, BUT, some triple trees also used M7. They’re very close so yours may be that.

So M7 x 1.25 pitch?

[RAFster122s]

Naturally the M8 isn't going to thread into the M7 hole if that is the case on your triple tree...obviously. And they are so close in size it could be easy to confuse them. The bolts on my triple tree are chromed it appears, so that might be a clue on you sorting out the difference in your bolt collection from disassembly.  The M7 will stand out in a pile of M8 bolts...but if mixed in a M6 and M8 pile it might not unless the bolts are chromed like mine.

Good luck sorting it out.

David

[Pin2Hot]

It was an M8x40 - 1.25 pitch bolt.  Turns out quite a bit of powder coat got caught up in the threads for the lower fork clamp bolts.  I got myself a M8 1.25 tap and chased the threads.  Now the front end is coming back together.  Thanks for the input everyone.

Getting back together:


Also mocking up the bracket for the PCB, will be utilizing the old speedo/tach mounting plate holes:


Gonna be a tight fit:

[Godffery]

"Gonna be a tight fit"
 I would say too tight for sure.  It may work fine for a while, but eventually the rubbing of the wires on the neck will likely start causing electrical gremlins.
I've worked in R&D for a large Moto company and these kind of fitments in long term usage caused many unnecessary issues and were the Bane of our existence.   (Focusing too closely on form, can cost in critical function)
 Just a heads up.

 Dig'n the overall build, Lot's going on there!