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1978 SOHC: Tracker style

evill006

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Oceanside ca
I heard my baby run for the first time in 4 years last night. Its been a long time coming and I can almost see this rat-tracker going down the road.

I bough my machine on a whim while on a road-trip, with the intent to build a chopper out of it. I even bought a hardtail kit from TC Bros. Like most ideas it morphed into another beast. the same night, I brought it home, charged the battery, checked the fluids, put fresh gas in the tank and kicked it over... vroom vrooom!

Like most first timers, I started with a complete tear down of the motorcycle, not labeling anything, hoping for the best.. there has been a tremendous learning curve.

3 years passed; my lil 'ol scooter patiently waited for its day. In April I picked up the motor and with a renewed ambition I dug in and got working on it.

I've learned a lot and look forward to finishing this project of mine, pictures to come.
 
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frustration and despair..

The motor is running better than at first.. but not by much. I been tinkering with the carburetors, but can't seem to get it to idle properly. It will only start and stay idling (high) with the choke on. Even once warmed, I can only shut the choke half way before it sputters off. advice?

The timing is only eyeballed thus far and intent to have one of you pros go though the tuning, but i;d stilll like to try my best to get it as close as possible before calling a "real" mechanic.

I installed the front brake calipers and pumped brake fluid through the lines, leaving the purge open until brake fluid poured out with each hand pump. The calipers tightened onto the disk and remain tight even after i release the brake. The pressure remains and of course the wheel won't turn, ideas, thoughts and advice are welcomed.. .

The wiring is killing my vibe.. I m entirely retarded in this matter. I was able to use the original wiring loom thus far to get it running, but now cant seem to figure out the birds-nest inside the headlight. I won't be running a speedometer or tachometer, but will wire front and rear signal lights. i have found some wiring diagrams but feel dyslexic and dizzy each time i stare at it.

I live in Oceanside Ca. any assistance is humbly appreciated.

ps. not sure why, but I cant seem to upload pictures from my iphone, wtf?
 
I m sure there is wealth of knowledge to mine from this group and I would truly appreciate any advice in regard to my brake conundrum and really the entire build..

I installed the front brake calipers and pumped brake fluid through the lines, leaving the purge open until brake fluid poured out with each hand pump. The calipers tightened onto the disk and remain tight even after i release the brake. The pressure remains and of course the wheel won't turn as the caliper maintains pressure, what could be wrong here?

also, i still cannot upload pictures from my iPhone or PC, is anyone else having this problem?

thanks fellas
 
On the brakes have you cleaned the master cylinder bodies well, it sounds like the return port is clogged (very small hole in the bottom of the oil reservoir) if clogged it will not let the piston retract and let go for the disks. Crack you bleed screw to release any pressure so you can at least move the bike. If the return port is clear you might have a failed brake hose, the internal part of the hose can crack and create a check valve scenario blocking the fluid from returning to the reservoir.
 
There has been progress to report!

I had to replace the front lines for new set of Galfer Braided Stainless Steel Front Brake Lines - FK003D438-3. they look great!

The rear master cylinder was clogged with old brake fluid, I ordered a rebuild kit, cleaned the old junk and rebuilt it. Works great.

All brakes are installed and road ready, very exciting stuff.


I have also made headway on the electrical front, i have the tail lights wired, installed and functional.

The goal is to test drive it this weekend, could not be more thrilled to see this baby back on the road!
 
Yesterday I used a timing light and attempted to adjust the timing, runs much better! I was a bit intimidated to try the timing adjustment on my own, but i'm glad i took this on, happy with the progress.

Question-My carburetors have an accelerator pump, do the vacuum lines and original air box need to be used, in order for the accelerator pump to function? I am running on pod filters.

I bought a carburetor syncing kit/manometer and will try to adjust them tonight. One problematic symptom is, it will idle at high revs and even after warm it will die when i open the choke.. I've made the assumption that its is running too rich, but im probably wrong, what else could it be?



...and Are you guys able to follow the links i posted above?

I have not been able to post pictures from my iphone on this thread for a long time now.

I'm excited to show this community my work thus far, so I can get the full critique and advice.

Any advice?
 
The accelerator pump is mechanical, works when throttle is opened by pushing an a rod. High rpm's at idle is usually an air leak around the intake boots. get a propane torch UNLITE spray the gas around the intake boots while running if rpm's increase you found your leak. Get the carbs sealed proper and idling decent before you sync the carbs.
 
These carbs have a high idle cam for when the choke is applied. If it dies when you open the choke then it is lean, check the idle jets for being plugged.
 
I tried the propane test method, there was no change. Inspected all intake boots, they seem properly fitted.

The idle jets are clean as a whistle, see my carb rebuild picture above! :)
I think all idle crews may be too closed at one turn from seated. I will open all 4 to 1 1/2 turns and see how that runs.

On the bright side, I took it out to dinner last night. Feels great to have a working machine. Gets a ton of looks, sounds great with straight 4 into 1 pipes, i'm stoked!!
 
I want to pick each of your brains, you won't hurt my feelings. I have a huge learning curve ahead, you guys can help by sharing some hard-knocks.

There is an oil leak from what looks like near no. 2 exhaust, I know they all leak a little, this is more than a little. Any thoughts?

The seat will be vintage/distressed brown leather, in a old school diamond pattern.
The tank and will eventually be dark metallic root-beer, with gold and black.

I also have BMX style handlebars to install.

Thanks for creeping, now comment!
 
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Update! It's been a year since the last video, I've made a few improvements,but I still had a pesky oil leak from the oil filter. I've had a hard time finding the gasket kit for the oil filter and mounting bracket, any ideas?
 
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