Topic: Jakal cb550 project

[SOHC4 Cafe Racer Fan]

Nice work. The support structure looks rather robust.

[Darren Jakal]

Robust, ha I know a euphemism when I see one ; ) Thanks for your encouragement Fan !

Yea, this is the result of making it up on the fly and learning as you go. Overbuild and then test to destruction - usually, but not this time. I am also integrating the mirrors and signal lights into the structure so it needs to be able to handle that and not blow apart on the highway (winds here can be brutal).

It’s also kind of the result of making in a way to help determine a bunch of variables (hand, handlebar clearance, light height, cable routes etc), so it’s a bit more development jig than I final production version. I’ve got the math now so making multiples also becomes a possibility (no intension but nice to have the option).

Take care, dj

[SOHC4 Cafe Racer Fan]

Robust, ha I know a euphemism when I see one ; ) Thanks for your encouragement Fan !

Yea, this is the result of making it up on the fly and learning as you go. Overbuild and then test to destruction - usually, but not this time. I am also integrating the mirrors and signal lights into the structure so it needs to be able to handle that and not blow apart on the highway (winds here can be brutal).

It’s also kind of the result of making in a way to help determine a bunch of variables (hand, handlebar clearance, light height, cable routes etc), so it’s a bit more development jig than I final production version. I’ve got the math now so making multiples also becomes a possibility (no intension but nice to have the option).

Take care, dj

Overbuilt in a good way.  I like the shape, too.  What material are you making the actual fairing out of? Carbon fiber would kick ass.

[Darren Jakal]

I'm no good with wet work.

I'm going to try my hand at flow forming thin aluminium.

[SOHC4 Cafe Racer Fan]

I'm no good with wet work.

I'm going to try my hand at flow forming thin aluminium.

Excellent!  My buddy has done 2 full fairings in aluminum.

[Darren Jakal]

Cool, Fan, be great to see pics of them!

cheers, dj

[SOHC4 Cafe Racer Fan]

Cool, Fan, be great to see pics of them!

cheers, dj

In order:

(1) "Una" -- Ducati Monster-based build, with custom aluminum seat, belly pan, fenders, trellis/girder fork covers and front cowl

(2) "Legionnaire" -- Yamaha R6-based build with custom aluminum seat and fairing

(3) "Hollowpoint" -- CB550-based with custom aluminum seat and fairing.  This bike was rough finished in about 5 weeks, but features an underslung shock, custom subframe.

[Darren Jakal]

Nice Fan ! That's some great work. Hollowpoint is sort of what I'd like to try one day (a full fairing that is).

Thanks, dj

[Darren Jakal]

I could use some help with finding the head tube angle for the 78 550K model. I know I found it once as I made a jig to hold the front end off the bike and I used an angle I found somewhere on the web (I thought it was here, but whatever).

Anyway I need to lock down some things for the fairing and need a baseline for setting the headlamp angle.

My plan is to make the plate that the lamp attaches to perpendicular to the line created by the fuel tank (90 degrees). I will then provide some adjustment for vertically aiming the lamp itself (I’m using a lamp ring that has left right adjustment already).

But how much adjustment (degrees from vertical)? Up and down or just some down adjustment?

Is the low beam angled down somewhat already?

If I could find the head tube angle I think that would help me determine how to position the fairing relative to the frame for at least being in the ballpark for a properly aimed headlamp.

Any comments / help appreciated.

Cheers, Darren

[Darren Jakal]

Cool, thanks Cal,

dj


Found some numbers for rake and it's 64*.

[RAFster122s]

Harbor Freight has a cool magnetic angle finder I have used when doing construction as well as other stuff. It tells me the driveway is an 11 degree slope (...or 79 degrees).  It has a magnetic base.

[Darren Jakal]

Great info RAF ! Thanks,

I think I found the position of the fairing (pretty much level with the tank bottom) and there is quite a bit of tilt adjustment that I built in. The lamp bracket will have a few degrees of adjustment also, but in the end I'll prolly aim it when the bike is done and me sitting on it in the prescribed manner I have found on-line.

Close enough to continue. Found some large pieces of fir the other day to make the flow form molds from. Just need to build a solid block and get it milled on the 5 axis cnc router. Take the temper out of the alu and get forming.

Cheers, dj

[Darren Jakal]

I finally got the wood block together and got it cnc milled for flow forming the fairing blanks. I still need to clean it up a bit and fill some cracks and seal it. I'd like it to last for a few tries.

I essentially divided the bullet shape of the fairing into 4 equal parts and I will make 4 separate panels to form the finished product. I'll roll the aluminium sheet into a rough cone and make some brackets to clamp it in place and then flow form from there.

Anyway, I'm away for a few weeks so it will have to wait until I return.

Take care, dj

[Darren Jakal]

Making progress but it's slow. Made a few items for cleaning the gas tank. Two stoppers that seal it up pretty good. I want to fill the whole tank up with acid and then flip it over and finish filling through the gas valve hole so that I can get the tank clean right up to the top (the opening is depressed and it would trap some air bubbles).

Other than that I've been bashing aluminium and fixing the forms (steel wool and epoxy and then some JB Weld to finish). I first tried bashing some generic 18 gauge aluminium and then tried again after annealing the blank. Much easier.

I have a line on some 5052 that I will try next. Dam this is no cake walk. Lots of work, but I can see it getting somewhere.

Anyway, that's it for now.

cheers, dj

[Darren Jakal]

Pretty good learning curve when it comes to this stuff. I've already figured out a few things that should make producing the other 3 panels a little easier.

I couldn't wait to try mounting the first attempt to the subframe. Worked better than I thought it would. I need to make 3 more panels and this one will probably find its way to the bottom quadrant. I hope to progress in my abilities and the other 3 should be of better quality (although there is still much to do to finish this panel and make it look as good as possible). Fingers crossed.

later, dj

[SOHC4 Cafe Racer Fan]

Close to my Thruxton fairing.

IMG_3393 by Donald Leonhardt, on Flickr

[Darren Jakal]

Nice bike Fan ! Great fairing.

cheers, dj

[Darren Jakal]

Making some progress, but still figuring out a bunch of things (like cutouts for the handlebars and forks and how to best trim the aluminium sheet - I need a throatless bench shear I think).

Anyway, first attempts at a windscreen mock up. This is a simple version that curves in only one plane. Might work, but I'll eventually make a form to make a three dimensional domed one out of polycarbonate.

later, dj

[SOHC4 Cafe Racer Fan]

Darren,

I was looking closer at your fairing subframe.  Assuming the circular piece is steel, I think it might be "overengineered."  I doubt you are going to race it or building the bike for outright performance, but you might be able to lighten the structure (while maintaining its strength) with aluminum tube and plate.  If weight is not a concern, carry on.

For reference, here's some photos of my fairing subframe.  It is robust as hell, but also light.


IMG_3387 by Donald Leonhardt, on Flickr

IMG_3388 by Donald Leonhardt, on Flickr

[Darren Jakal]

Hey Fan,

Thanks for your interest and comments !

Pretty much everything is aluminum except for the two lower support arms that are made of thin wall tube steel (pretty light). The circular plate in front is aluminum and the big ring is only temporary to hold everything in place. Overall not that heavy, but thanks again for your help.

cheers, dj

[SOHC4 Cafe Racer Fan]

Pretty much everything is aluminum except for the two lower support arms that are made of thin wall tube steel (pretty light). The circular plate in front is aluminum and the big ring is only temporary to hold everything in place.

Nice!

[Darren Jakal]

It's been a while since I posted, but I've not made a ton of progress on the bike. An early snowfall (almost 2 feet in my area), replacing the engine in my Outback (dropped in a JDM with 70K on it) and a knee injury has kept me occupied and away from working on the ride.

I did, however, pick up a 1977 CB550K roller for $150.00 CDN pesos. It has some ugly welds where someone attached something to the front of the frame and I wonder if this has weakened the frame or if I can carefully cut this stuff off and grind/sand it back to original condition. I like the idea of having another frame to play around with, but this one is complete and I'm not sure if I want to cut it up. I'd really like an old frame that someone did a #$%* job of modifying and use that as a start.

So, now I have the proper rear hub for my bike (and a bunch of other good parts that would cost a fortune if I bought from the local wreckers). I've pulled it apart and the cush drive rubbers look good but they are pretty hard. Now never having seen cush drive rubbers or felt what how hard/soft they are I've no idea if these are good to go or if I should try some kid of treatment on them (I've read a few posts on this and I'll need to look again).

The bearing retainer had been drilled and some kind of glue/sealer was stuck in there, but I've managed to get it cleaned up enough to work on. I've put it all back together and threw it back on the bike. There is plenty of slop in the cush drive, but I didn't tighten the retainer down that much.

So, what is it that keeps the cush drive/sprocket aligned with the rest of the wheel? There is a rubber seal on the final plate that is worn out but how do I know if this hub is OK or needs something else?

Anyway, I'll finish here, but I still have a bunch of things to figure out before the bike is on the road (like where to get a socket for getting at the two inside spark plugs).

Cheers, dj

[Darren Jakal]

Cool Cal, I knew you would have an answer 

[754]

Jeez i forgot you were working on that metal forming .
 Try to get 3003 aluminumm not sure how you anneal, but I use the soap trick.. worked goid the few times I used it.  I like using my shear forvtrimming alum, had a Metabo but I broke it so I got a great deal on a Hitachi. The princess Auto ones are crap, can't cut a tight radius, and can't trim small slivers off, they jump into the work and ruin it.
 Here is a shear pic and the factory plug wrench you need.

[754]

 I think your forming would be faster if you  screwed a flat piece across the female form, about 12 screws or more per side, then start forming, with repeated annealing. It will stretch and thin,
 How thick is the material ?