Topic: 1979 CB650 Cafe - Some updates

[Jay_kent]

This was a free 1979 cb650 given to me by a neighbour. Sat in a field for nearly a decade before I got to her.

Here is how she started


Went to this


and finally ended as this






I coudn't get the bike to run well, and there was a couple of things that I wanted to finish, like paint the frame, redo the seat. So with winter coming up it was time to tear her down.







I'll be posting more images later with the engine tear down, my getto homemade tools and blast cabinet later. More images are located at my blog linked in my signature. I've got a few ideas I'll be posting and am looking forward to your ideas and honesty.

Jay

[Jay_kent]

So in between my brothers house renovation, (transforming a century old home that was a duplex back to a single family) to kids swim and gymnastic lessons, I have been working on the engine a wee bit. Over the course of the summer I bought an almost complete bike because I needed the Stator, and Rotor for mine to work. Turns out the engine is my guinea pig for the tear down. I tear down the spare then work on mine. Works out well as I'll have two running engines by the end of it.

The one on the left is the 1979 engine, the right is an 1980, the '80 is the spare


The 1979 engine was in better shape, seems like the spare engine was left outside with one spark plug unistalled so it was a wee bit rusty in one cylinder.

here is the cylinder head.


a little bit of carbon build up


not too bad with the pistons


Now It's not that I'm cheap, I'm just resourceful and would rather spend my money on a gasket kit or new part so buying specialty tools is not my strong suit. I'd rather make them so I introduce my recipe for a valve compressor.
Take one unusable 5" C-Clamp, one 3/4" conduit pipe and mix in an earth magnet and voila you're done.



How it sits on the cylinder head


Compressed Valve and keeper remover


Works pretty good actually.

So in the works is polishing all covers and rocker head. Engine will be blasted and painted glossy black. I'm working on a 2 carb for 4 intake setup but I'll be using the BS34 mikuni carbs because I've got 2 sets of those. I've worked on a couple of bikes using these carbs and I like the ease of them and the availability of parts and Jets from places like mikesxs. CDN site is herehttp://www.xs650direct.com/. I'm looking for ideas for a manifold for the 2 into 4 setup. I know the cycle xchange has a setup using vm32s but its for a cb750 and I don't think they sell their manifolds separately.

That's it for now

Jay
http://colt-pixy.com/1979cb650/

[Jay_kent]

Quick update, I'm waiting for the gasket kit to come in so I decided to port and polish the heads. This is the first time doing anything like this. Is there anything I should look out for, beware of? I'm mostly taking the casting marks off as well as sculpting the valve guide area. I figure if the grinder doesn't run smooth through the port then the air won't so it'll be ground down.

Comparison Shot of one untouched and one started.


A finished exhaust port


I know that it's not baby bottom smooth but I'm pretty happy with what I've managed to get accomplished.

I'll be running clip-ons this time round so with a spare triple tree top I cut off the handlebar clamps with a sawsall and a metal blade.

Untouched


Touched


My plan is to grind clean, then braze in an aluminum sheet so I can put in LED indicator lights. I'll be running a small tach and speedo so I haven't decided if I'll cut off the mount points for the ignition switch and relocate that or cut off the existing headlight mounting points and get some ears. Decisions, decisions. mostly comes to budget. Either way it would make sense to keep one set of mounting holes to use for the tach and speedo.

Hopefully I'll have something a little more sexy to look at. lol

Jay

[Jay_kent]

Bit of an update, I ported and polished the cylinder head over quite a few series of nights. I'm using a Dremel as a I don't have a compressor large enough to  run a die grinder. Started out using a grinding stone where after reading a few tutorials I found that carbide cutters are the way to go. Found one at Princess auto that worked for the Dremel and that sped up the process. and it was only 6 bucks compared to the 20 dollars for actual dremel bits.

here's the results.
Intake port - left rough, people are of the opinon that it acts like the dimples of a golf ball. Air moves faster


Exhaust port - polished


I also polished the cylinder head to reduce carbon build-up and smooth the transition between deck surface and the combustion chamber as there was a bit of an edge that some say can lead to pre-mature detonation.

That's the good, now the bad. After all this I start to lap the valves as the last thing I needed to do before paint. I was having trouble getting the number 3 cylinder intake valve in. When I removed the valve during the tear down it didn't come out with a fight but I thought it was just the valve. As it turns out it's not the valve but the valve guide. FRAK. Now the mystery why the number 3 cylinder was running colder than the rest is solved.
Luckily I bought a spare bike this summer so that head is on the table getting the port and polish done to it. And I checked the valve guides on this one. Guess the good thing is I've got the right tools and the experience so it's going faster.

Got my gasket kit this week as well, it's complete and came in within a week. Good guy that Dan from D's unusual finds on ebay.

more pics up on the blog

Jay

[Jay_kent]

Between the usual kids and work, I've been slowly working on this project. The 2nd head is almost finished with the porting and polishing. Amazing how quickly things go with a little experience. Since I and my neighbour who knows a lot about bikes were at our end to why the bike wouldn't run this incident with the valve guide has a positive note it's one less than to trouble shoot when it gets rebuilt this spring.
Decided that its also a good time to replace bearings and seals. The forks had a little oil on them, so new seals it is and a good thing too.




My handy dandy fork seal driver


It feels good to be scratching things off that list.

Since everyone loves a mystery, any guesses on what I'll using this for?


And some concept sketches for the tail section. Just trying to get an idea of a direction.






Steering Stem bearings come in this week and I still need to mock up the bike to figure out the tail section and rear-set positions.

Jay

[Ogri]

Since everyone loves a mystery, any guesses on what I'll using this for?

Rear drum ventilator ?

Looking good. Preferred the earlier green 

[traveler]

get the seat as low as you can on the frame...that 1-2 inch border between the frame and the seat looks BAD.

Last last color green really looks poor, IMHO

~Joe

[sammyboom]

I'm guessin(looks like a salt shaker) a tail light holder or gauge holder.
i'm with the others the 1st green looks good.

Since everyone loves a mystery, any guesses on what I'll using this for?

[Jay_kent]

Thanks for the honesty guys about the color. The reason for the color change was it looked too much like a Kawasaki color. The other green I liked but it was too flat. I'm close to a color and will be pointing up my choices soon for a debate.

Pretty much everything on this bike will be changing. As others pointed out, the seat did ride up too high, it was my first attempt at fiberglassing a seat with a modified gas tank for the hump. The next seat will be closer to the frame rails. The idea is a low lean machine.

As for the mystery shaker, you'll have to wait for a bit. Things are working out better than I hope for it but I've got to decide on the execution.

Jay

[Jay_kent]

Since it's my intention to blast a couple more motorcycle parts like the spare engines and frames I have kicking around. I thought it'd be wise to build a box so I'm not wasting all that sand outside. Plus it's warmer in the shop. Luckily for me I'm a bit of a pack rat and collect all sorts of stuff. So with the spare wood I had lying around I built my cabinet large enough to put my frame into.

It has a tapered bottom so that the sand will collect and I can brush it all back into a bucket underneath, ready for re-use. It's got a tempered glass top so light can get in. Plexiglass front that I had extra of. I had scrap fireplace screens that I've used for the table for the parts to sit on while they get blasted. The screens allow the sand to pas through.

A hole on the side for the vacuum to collect the finer dust and 2 fluorescent lights up top for extra lighting. Total cost. $4 dollars for the denim jacket from Value Village that I'll be cutting the sleeves off and attaching gloves rather than buying the proper gloves. Mostly because I didn't want to pay for them.







Now I'll get off my ass and get to chopping up the frame, welding on the back hoop and everything else that needs to be done. I'm looking for a late April finish. lol

[Jay_kent]

Here's where I am with the gauges so far

I just really like taking something out of its context and using it for something else. I found the perfect soloution to small guages that I think will work perfectly.

At a local dollar store they had these large seasoning shakers you'd find in a pizzeria or some similar restaurant. They were cheap, about 2 bucks each, stainless steel and fit the bill for what I had in mind. I'll be cutting out the perforations to so that you can actually see the gauge underneath. I'll have to take apart the old motorcycle tachometer and speedometers for this. That way I'm guaranteed to have an accurate ratio for the tach and speedo rather than getting an aftermarket one. Sure I can fork over the cash for a set of mini gauges but what fun would that be.

I'll be posting a vid of how I took the gauges apart at a later date for those that want it.

You've seen this


Taking some measurements, Luckily it's the same dimensions for Tach and Speedo


Trial Fit


Transfering dimensions


Oh NO




Bolted down


Cheap material can be found everywhere


What's left is to make the faces to fit, cut the old clear covers to fit inside the cap. I'll be folding over the edge to create a seat for the clear cover to sit on with an rubber gasket underneath. Then just put the lid on and figure out a way to keep it attached to the bike.

Jay

[sammyboom]

I win....so what's my prize.lol...... anyways like the progress keep up the good work.  Can't wait for the finished product.

[Jay_kent]

Haven't haunted here in a while but some updates

Trimming down the height


Tabs that will be the seat for the glass window.


Outline of the opening of the viewing window


Mockup faces - just to get the size and placement right


Comparison Shot


Now just need to get the lid completed. I'll be doing a bottom mount as well I've got a frosted ring with LED to be put inside before everything gets locked down. The frosted ring is for illumination at night. Kinda like bmw halo eyes. it won't be visible but (hopefully) will provide some decent light. not that it matters  

More to come later

Jay

[Jay_kent]

About to start with the rear hoop and the tail section, some ideas I'm playing with
Seat 1


Seat 2


Seat 3


Seat 4


I'm feeling number 1 that way I can have a smaller hump, with the plate up over the wheel. Hand out the feedback please and don't worry about the color, that will all change.

[Jay_kent]

Managed to get some things done, thanks for the votes on the seat, I went with the first one. I liked the lines of it, plus I needed a place to hide the taillight and license plate above the wheel.

I did a few cardboard profiles to get the right shape.

Next was a plywood wood mockup with ribs that will give the actual look of the unit. This will be come the base for my mold.



I was going to try to hammer a metal hump but I've decided to go with fiberglass as I've done that before and I'm under the gun to get this bike finished. So to fill in the spaces I've used a combination of pink Styrofoam and spray foam. Kinda looks like a fat ugly cake.



With a bread knife, surform (autobody cheese grater), and some sandpaper I sculpt the mold into shape. And I've almost got my mig welder working. Very excited about that. More to come





It was wrapped in packing tape then I laid down my patterns of fiberglass on it. A trick from one of the guys at a http://www.fiberglassforums.com I go to lays out his fiberglass dry and keeps the layers in place using spray adhesive before he wets it out. That's as far as I made it this time. This will be my fiberglass mold for the final hump.



I also managed to drill out my brakes. Luckily I've got a drill press. Use cobalt bits. Didn't break any. Plus I used cutting fluid as well.







I've got metal tabs to weld to the frame  for mounts and some extra bracing, but time is not on my side. argh.

[Jay_kent]

Back on the bike after a short hiatus with a new to me Mig welder. Getting that ready at the shop so I can start welding all of the metal bits and pieces.

I've got the mold complete for the seat hump and it turned out not to bad. From another forum, one guy suggested that you cut the fiberglass patterns out then lay them in/on the mold with spray adhesive. Once a couple of layers were in place, wet them out with your favorite epoxy. Worked the charm. The only problem was the type of resin I used. I purchased mine from Canadian tire and the resin is quite thick so a couple of spots didn't get wet.  When I go to do the final layers I'll spend the extra money from a professional store and purchase fiberglass epoxy that has a lower viscosity so it wets out faster and more thoroughly. On to the pics, that's the important part.

The seat hump is my female mold. It currently fits the rear of the motorcycle frame okay but is a little wider than I wanted so I'm laying out the mat fiberglass inside the mold. This is my mold after I wet it out.



Mold test fit on the rear of the frame.





I'm also going to run with a tire hugger on the rear to keep dirt and water out of my airboxes. I originally was going to use the chrome rear fender but I'm opting for something a little different that will float on the swingarm with the tire.

I first took 2 layers of foam camping pad and taped it around the rear tire. I sealed it with packing tape. This will allow the mold to come off the tire easier. Then I did the same layering with spray adhesive. One trick I found that worked well with tight curves is to tear the mat fiberglass into chunks so the strands of fiberglass over lay each other and they form around the curve better.





Layering of the fiberglass mat for the tire hugger and seat hump. That way its only one large batch of resin.



First round complete.



Before I wet out the resin in the seat hump I trimmed all of the excess strands. Better now with a pair of scissors than later with a saw.

During this time I'm also working on the guages, cutting parts off the frame. The welder will be wired at my shop this week so I'll be doing a couple of days of practicing before I get onto the frame. Engine has be completely sandblasted and is ready for paint. Just want to get a oven to bake in.

~Jay

[Jay_kent]

Twisted, No problem with the pattern man, when you're ready. I've seen what you're working on for the wedding. Gutted my brothers century home, plaster dust in the lungs sucks.

Made some head way on the custom gauges for the bike. The holes in the lids were removed. Stainless is a pain in the ass to work with. Tough as hell. Also I took apart the existing gauges to get at the glass inside them. With a glass cutter and a grinding wheel used for stained glass I got the lenses shaped to fit inside the salt shaker lids.

Glass removed between the two steel shells



Glass cutter used for stained glass, final shape done on a grinder



Fits pretty good


Removing the center holes. Broke two scroll saw blades before I busted out the trusted cobalt drill and drilled a round robin of holes. Finished off back on the scroll saw to cut the tabs between each hole.

For reference on the size. The other gauges are much larger by comparison.



Love the pattern on the serving tray. Might just leave it like that. Indicator LED with chrome bezels will be going on the left side if I keep the image.

[Jay_kent]

Alright, this may not be the best idea I've had but I'm ditching the 4 bank of Kehin carbs for a dual Mikuni setup. I perfer them to work on and the parts and jetting are much easier to get.

Here are the set of the Mikuni carburetors when pulled from the Yamaha xs400


Freshly cleaned with soda, just a boil afterward to dissolve the rest of the soda and we're good to go.


Because I'm running a 1 into 2 setup the carburetors have to be spread wider so that each one sits in the middle of 2 cylinders on the Honda head. The original return springs aren't very strong and there is a concern the engine cylinders will create a vacuum strong enough to keep the carbs open, I've decided to maintain the Honda push-pull system. Luckily I had a crap pair of cb750 carbs that was missing parts. I'll be modifying the throttle link to fit in between the Mikuni carbs
I'll thank maritime biker for the image of not being able to close the throttle.


The throttle link bar has been cut down. I'll be using existing parts from the carbs for adjustment so the throttle  linkage will be modified to fit onto one bank with the other end drilled and tapped to fit the adjustment linkage.


The carb bank roughly mocked up. A bolt will be inserted into the end of the original throttle linkage and modified to accept Mikuni throttle adjustment. Here's where it sits right now.


I've also bobbed the fender this evening.

The fender in "original" condition.


Taped where I'll be trimming the ends off.


The final sized fender


Unfortunately I won't be finishing the bike on its time as it's only a couple of weeks to my birthday (the date I wanted to finish) and I've got sooo much to do. I haven't even touched the electronics, nor painted and rebuilt the engine, frame needs bits welded to it, and then there's the all of the glassed parts that need finishing and painting.

until next time

~J