Bride of Frankenstein - a cure for leftover parts cluttering the workshop.

mustangfrank

Well-Known Member
#61
I realize that hydraulic brakes are not at all an "old mini bike" thing, but I began rebuilding the bike's goofy Honda Inboard Disk this morning and figured I'd post a couple photos.

The caliper was already seized solid when I got the wheel almost 16 years ago, and it had been sitting dry, with no line connected, in a dusty corner of my garage ever since. Clearing the line took both master cylinder pressure from one side and a mityvac pump pulling on the bleeder from the other. Eventually, a big black plug of gook appeared in the bleeder tube. Once I pushed that through, I closed the bleeder and had no problem pumping the pistons out. Overall, it's in surprisingly good shape. There was a lot of crusted-on crud in all the crevices and some jellied residue inside, but I had been prepared for much worse. The pistons are probably reusable, but I already purchased new ones, along with new seals and boots. Now it all goes into the ultrasonic cleaner!

View attachment 283049 View attachment 283050
Not that unheard of, I've seen a few run the little sealed brake systems swapped off of newer bikes. Digging the little 2 piston caliper.
 

Tanshanomi

Well-Known Member
#62
Ultrasonic bath, then soda blasted, back in the ultrasonic tank again, then a couple coats of Eastwood Brake Gray. The brake caliper is ready for reassembly, but the brake pad locating pin disappeared at some point over the last 15 years, so that's on order and further assembly will have to wait.

5413.jpg

Since my trailing axle arrangement puts the fork legs farther forward relative to the wheel hub than the stock VTR250 forks were, I had to trim off a portion of the air scoops on the caliper side for clearance. In the photo below, the intake scoop is the original height at the extreme right, and the red grease pencil shows how much I removed from the rest of it. It will definitely need some additional dressing before it gets painted, but I'm happy with how it came out. Concerning myself with aesthetic finishes is still a long way off.

IMG_3278_HD.jpg
IMG_3279_HD.jpg
 

I74

Well-Known Member
#63
Ultrasonic bath, then soda blasted, back in the ultrasonic tank again, then a couple coats of Eastwood Brake Gray. The brake caliper is ready for reassembly, but the brake pad locating pin disappeared at some point over the last 15 years, so that's on order and further assembly will have to wait.

View attachment 283293

Since my trailing axle arrangement puts the fork legs farther forward relative to the wheel hub than the stock VTR250 forks were, I had to trim off a portion of the air scoops on the caliper side for clearance. In the photo below, the intake scoop is the original height at the extreme right, and the red grease pencil shows how much I removed from the rest of it. It will definitely need some additional dressing before it gets painted, but I'm happy with how it came out. Concerning myself with aesthetic finishes is still a long way off.
That caliper looks awesome !
 

Tanshanomi

Well-Known Member
#65
My spare brake line is just a couple of inches too short. Damn.

IMG_3285-XVGA.jpg

I taped the cheap-o plastic fenders in place, just to get an idea how they'll look. I'm not really digging the super angular front, but it's what I'm stuck with, so it is what the bike is going to have. All the clutter around the bike in this shot doesn't help (my workshop space is pretty cramped and desperately in need of a good reorg/tidying up).

IMG_3287-HD.jpg
 

Tanshanomi

Well-Known Member
#66
I'm working on the exhaust. Since I don't have $600+ dollars to drop on a proper tubing bender and dies, I bought a used, 1" diameter electrician's conduit bender for $30. Unfortunately, I had no idea how big it would actually be. It's a monster.
Here's my first attempt:

IMG_3299.jpg

The radius of the bend was way, way too big for my purposes. That pipe is exactly where your left thigh is going to be when you put your feet down at a light. Ouch!

IMG_3300.jpg

So, I bought a pre-made header pipe. It had a much tighter bend, which is good, but this one pointed straight at the rear frame tube. So, I cut it down and matched it to another section of tube that I had bent with the conduit bender just slightly.

IMG_3301.jpg

It tucks in so much better! It will still need a heat shield, but definitely a workable fit.

IMG_3302.jpg

I have most of the intake plumbing cut to shape, too. Once I have all that ready to go, I will drop all the parts by my local welding guy and have everything pieced together properly.
 
Last edited:

Tanshanomi

Well-Known Member
#69
After a disastrous attempt to weld up an intake tract myself (which I wisely refrained from photographing), the exhaust pipe and intake components were dropped off at my friendly neighborhood welder this morning. He expects to have them done in a week or so.

IMG_3374.JPG

I also got a bit more done on the front brake. The VTR250 didn't use an actual brake stay. Instead, there was a boss cast into the fork lower that engaged a slot in the brake plate when the wheel was inserted. Not only do my forks not have that brake boss, but the forks are now forward of the axle anyway. That's actually a good thing, because it frees up that space for an additional stay assembly. The stay arm is 7/32" (5.5mm) thick steel. It mounts to the axle at the bottom and has a 90-degree bend on the other end for transferring brake force against the back of the fork slider. I cut and ground an alloy block to be a tight fit inside the brake panel slot. I still need to mount the block to the arm. I am planning to use a pair of M8 x 1.25 socket head screws with heli-coil inserts in the alloy block for strength. I'll also make up an additional bracket that will tie the top of the plate to the fender mounting bosses for a little more strength (and because the brake plate could theoretically rotate the other way when the bike is rolled backward).

IMG_3379.JPG
IMG_3378.JPG
 

Tanshanomi

Well-Known Member
#71
I bored a channel through the frame backbone tube for the forward shock mounts. I managed to drill out both sides so that it's actually perpendicular and level. The cross tube is 5/8" OD x 0.156 wall, so the ID is about 8mm. I drilled and tapped each end for M10x1.25 bolts, so the whole thing should be pretty damned stout.

IMG_3443-web.jpg

You'll notice that the shock bodies are noticeably offset. That's intentional. You may remember that I had to offset the swingarm to the left to align the chain and rear wheel. As a result, the right-hand shock would wouldn't clear the frame backbone when mounted inboard of the swingarm boss. On the other hand, the left shock body is inboard to keep it further from the heat of the exhaust pipe and keep the frame mount as short as possible. On the longer right side, I'll add a gusset behind the cross-tube (the ghosted yellow triangle in photo) just to beef up the frame connection a little. For now, I'll file the area down to bare metal and tack weld the crossbar in place. My welding guy can finish it up properly—along with all the other frame joints—once I'm done with the mockup build.

I positioned the shock mounts as far up and forward as practical in order to minimize the seat height. That helped get my seat height down about an inch from my previous calculations, to 33 inches. This pleases me.

IMG_3444-web.jpg

With both ends of the shocks positively located, it has become a fully bolted-up rolling chassis for the first time. The cheap-o shocks were intended for the front A-arms on a youth four-wheeler. They're way underdamped, but my unscientific sit-and-bounce test says the spring rates seem about right. Rear wheel travel is limited to only a few inches, so it's either going to be rather firm or bottom out over big bumps.

It felt really good to take it off the stand, put my weight on it, and roll it around a bit. It's starting to feel less like a collection of parts and more like an actual motorcycle (albeit a pretty weird one).
 

I74

Well-Known Member
#72
You are gett'n there !!
That suspension ought to work fine.

Like that seat.
Kind'a reminds me of a TT one.

What color/colors are you going to paint it ??

Lastly,,

Where's the battery going to live ?

I
 
Last edited:

Tanshanomi

Well-Known Member
#73
That suspension ought to work fine.
Mostly undamped with 2-1/2" of travel. Should have the ride quality of a '50s plunger frame bike.
What color/colors are you going to paint it ??
Paint? What is this "paint" you speak of?
Nah, to be more serious, the plastic tank will stay it's moldy red-orange, possibly with the addition of some black and white adhesive vinyl panels (to hide the permanent discoloration that will forever spell out "Can Am" on each side). The fenders will be white, and the front wheel will be painted Kawasaki Gentry Gray to match the rear wheel. Everything else that needs painting will be rattle-can gloss black
Where's the battery going to live ?
I'm not 100% sure, but my current plan is to make a battery box for a narrow AGM battery between the swingarm and engine. It depends on what will fit. I am hoping I can squeeze a Motobatt MB7U in there.

And thanks for taking enough interest in my silly project to formulate questions!
 

Tanshanomi

Well-Known Member
#75
A non-update: Things will be a little quiet with this project for a bit. Due to having a nasty bit of melanoma removed, my workshop is off-limits for the next 3 to 4 weeks while I heal up. Fortunately, they’re confident they got it all, so that’s a blessing.

As a public service announcement, wear your sunscreen kiddos! (Especially all you fair-skinned Irish boys and girls.)
 

Tanshanomi

Well-Known Member
#76
After nearly two months on the sideline for post-surgical recovery, I was able to get back into my cluttered workshop and make some progress on The Bride.

I fabricated the weird torque arm the front brake required. It's pretty monstrous by design and the big, black slab looked seriously homely.

IMG_3688-web.jpg

To help it visually, I added a bit of contour, and drilled some timidly-sized speed holes. I tried to make it less blocky but leave most of the meat. I was going to hit it with some aluminum-finish paint to make it a little less noticable. Then I found a can of metallic gold on the paint shelf, and I figured why not go with the “it’s not a bug, it’s a feature” approach and highlight it. It’s still not attractive, but now there’s more intention to its ugliness.

D3C60E33-1024x766.jpg

The next step is fabricating a bracket that will tie it to the fender mounting bolts on the fork. It's already braced against the back of the fork, so this will be just some reinforcement, as well as ensuring the brake panel can't rotate rearward when the bike rolls backward.

I’m also working on new steering stops. Since I am re-using the alloy collar I originally designed for another bike, the holes I drilled are totally wrong for the Panther/Shin San Tong frame. The solution doesn’t look terribly elegant yet, but it's not at all finished. However, I do have the forks stopping at the right point in their rotation at this point, so I’m pleased so far. In this pic, the bars are turned full-lock to the right.

60122D53-1024x766.jpg
 

Tanshanomi

Well-Known Member
#77
This morning before work, I fabbed up the brackets that will tie the brake panel stay arms into each of the fender mounting bosses on the fork legs. I cut them out of 1/4″ alloy plate with a hack saw, sanded the edges with a 1" belt sander, then drilled the bolt holes and “speed holes” on my benchtop Craftsman drill press.
I have some low-profile button-head allen screws on order to replace the big socket heads on there now.

IMG_3743.jpg

On the caliper side, a pair of M6 bolts will attach the upper bracket to the main arm. Remember, the majority of the braking stress will be transferred directly from the brake arm to the fork leg. The bracket is just there as a backup, and to prevent the brake panel from rotating when rolling backward.

IMG_3745.jpg

Closer up, you can see that small spacers will be required between the two pieces.

IMG_3741.jpg

On the other side, the wheel cover with the scoops in it is just cosmetic. It does need to be positively located, but are no rotating stresses on it. Thus, the stay arm is much smaller, and will attach to the upper bracket with only one M6 screw.

IMG_3744.jpg
 
Top