So I decided it was time to give my daily rider little pip some much needed attention. For starters, the seat needed better padding and nicer upholstery. Since I am about to be doing the CB750 seat, I figured it would be good to get some practice on the 125 to see if I can make a seat nice enough for the 750.
Step one was to cut up and stitch a new seat cover. Unfortunately I forgot to take good photos of the process, but after several hours on my mom’s sewing machine I managed to cook this up.
This was my first attempt but it turned out half decent, I’m pleased. I think my next shot for the CB750 will look very passable. So after I finished sewing that I just cut out and glued some neoprene to the seat pan. I then glued a layer of soft, thin foam on top of that for extra comfort and to keep the pleats puffy. Here is the finished product after I riveted the cover on and re-installed it to the bike. Note that I am still using the aluminum street sign seat pan I made for it originally!
I’m going to document the CB750 seat upholstery job much better I hope. Next I am going to rebuild the front forks on this little guy!
Kevin brought me the tank back today! Cue the pictures:
He mixed red with metallic silver and a touch of black to create a very deep burgundy-maroon. I’m not great with colors or their fancy names, there is probably a name for this exact color but to me it’s just plain perdy.
The bike was so excited it wet the gravel…
Kevin did the 2-tone emblems with a paint brush.
Finally getting there! To do list includes: seat upholstery, tail light mounting, replace pulser, mount carbs, and then bloody well ride!
So I finished wiring the bike awhile ago but forgot to even check for spark! Or maybe I was subconsciously afraid of what I might find. Sure enough when I turned it over with the plugs out there was nothing. All new NGK D8EA plugs, tried it with four different coils, and two sets of TCI units. So after all that I pretty much have it narrowed down to the pulser, which is not much of a surprise. That’s probably the reason the bike got parked for so many years before I found it anyway.
So here is the culprit! I adjusted the gap on them and was able to get very intermittent spark from one coil…So I’m pretty sure these bad boys need to be replaced. Luckily I have a parts bike in the yard (Arkansas style!) so I don’t have to spend another $100 for this unforeseen set back.
On a brighter note I got my starter button in the mail today and immediately set it up, it’s nice and subtle.
Works great! Once I mount the tail light the wiring will be 100% complete. Oh and replace the silly little pulser…
It’s about time I got on to the seat pan. First I pulled out my huge sheet of 18G sheet metal, measured generously the length and width of the bike where the seat will go, and loosely marked it off on the pan.
Then it was time to crank my headphones and cut it all up…And yes, I was angle grinding with my right hand while taking this picture with my left…I wouldn’t recommend this!
Before I started to cut it down to size, I shaped the metal to fit the curves of the frame, this took about 15 minutes of going back and forth from the bike to the garage floor.
Now that the seat pan has been formed, I can start to shave it down to the right dimensions.
Cut trim snip, another 20 minutes of loud noises and tinkering. But it payed off! Just under an hour of work and I have a nicely formed, light, custom seat pan ready to glue some foam to. The little square i cut in it is for the positive terminal on the battery. Due to the close proximity of the battery to the seat pan i didn’t want to risk a short so I cut that area out and the seat foam will be all that ever makes contact.
I still need to weld some short bolts to the under side to go with the mounting brackets I made on the frame. I will also drill several holes for the rivets to hold the upholstery on. The front will get shortened a bit once the gas tank comes back (this weekend) and I know exactly how they are going to interact. But that is all for another time.
Now that I’ve got school done for the summer I can finally make some progress in the shop. First order of business is to install the sweet MAC exhaust that just arrived in the mail.
It has tri “y” headers with a canister style (removable) baffled muffler as opposed to a megaphone. Not cheap…But great quality!
So I mounted it up and rolled the beast out to get a little vitamin D while I begin making a seat pan.
This header design is nice because it allows access to the oil filter and drain plug unlike many aftermarket systems.
If you notice, I also got some genuine italian gran turismo grips installed. Got the clutch perch, cable, and mirror on. Along with the throttle assembly I got from niche cycle. It is very simple and slick while still using the cb750 throttle cable. It’s coming together!
Next I’ll cut out and shape a seat pan.
I finally sat down and finished the wiring, it took me about two hours to do since it was my first time to wire an electronic ignition CB750. I have done a few viragos with EI systems and I can do them pretty quick now. The CB750 was more complicated because it has two separate TCI units. Here is the simplified diagram that I found and used. Gotta love the internets!
I know it looks like a lot of wires but it is really pretty compact since that’s all the wires on the bike, that will all be under the gas tank of course.
I just used one main fuse between the battery and key switch. The master cylinder I installed has a brake light switch built in, so I wired that into the harness so the front brake will trip the brake light instead of the rear. In the past I usually just use the rear switch but it doesn’t look as clean and generally riders use their front brakes more than the rear so it is a bit safer this way.
If you look close you can see that my ground-to-frame is about 2″ long which is awesome 🙂
On an unrelated note, I was walking to go get the mail and as I passed my girlfriend’s parked car something bright white caught my eye below the steering wheel. Upon closer inspection I found this!
Here i’m staying up all night wiring motorcycles and Jazzy is just snoozing in the car! What an easy life.
So like most old bikes I get, the front brake caliper was GROSS, and the master cylinder was shot. I completely disassembled the caliper, gave it a good ultrasonic bath, removed the flaking paint, and got this…
Once they dried I prepped and painted them with good high heat gas/oil resistant paint so now they look like this.
Once reassembled and installed, it looks great and once I hook it all up, should work wonderfully!
I bought 3 master cylinders so that I had a selection to choose from, black vs silver, and different bore sizes. I want the best for my baby!
After that was all squared away I wasn’t sleepy yet, at 1:30am…so I decided to finally get those pesky header clamps off. the deed is done, though it wasn’t easy. This here is an example of why you should ALWAYS replaced exhaust gaskets…
Funny side note, a stock CB125 front sprocket and a stock CB750 front sprocket. Can you guess which is which?
And I will leave you today with this, $80 worth of the highest quality neoprene foam available, this should make about 10 bike seats so it’s really not too expensive when you do the math. It is TOTALLY worth every penny too, it’s extremely comfortable.
Until next time.