Re: 78 cb750K won't fire up. (1 coil fires other doesn't)

Posted by mitchberry on Sep 11, 2010; 10:03pm
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/78-cb750K-won-t-fire-up-1-coil-fires-other-doesn-t-tp1425305p1458775.html

on the plus side, RANDOMLY, i started getting power to both coils, and spark in all 4 spark plugs.. but it still wouldn't fire up.   the coil in question had a much darker spark than the good one..

at this point, i think i need to change the plugs and keep going with it. the problem i'm having now is that i have probably 4 minutes or less crank time before the battery goes dead, and, i'm not heavy enough (178 on average) to kick the kick starter hard enough to make a bit of difference towards starting the motor...  

Usually, i laugh because when people try to start my other bikes, they have no idea how to make the kick start work properly to start the bike...

so, i have to mention i'm all too familiar with kick starts and what it takes to make one fire a motor, but i'm simply not heavy enough.   when i first went to look at the bike, i couldn't even budge the kick starter... the dude i bought it from was probably about 400 pounds... he stepped on it and moved it but ran out of breath after about 2 kicks and or broke the left foot peg loose of it's hold because he hadn't tightened it down like it was supposed to be.  (didn't harm anything, just.. flipped it upside down and almost racked himself when the foot peg gave way... )  

anyway, i have about 4 minutes of time, then 6 hours of charging on the trickle charger i have.. then 4 minutes.. then 6 hours of charging then 4 minutes.. etc etc....  so basically, whatever i do, i have to make sure i'm doing it well in those 4 minutes...

not sure why any of that matters to this post..

as for the points, and dyna coils and all of that, i'm not sure if they make dynas for the SOHC motors.. i sell parts for a living and was looking at them through our distributors, but wasn't able to find one at the time for an SOHC motor.  maybe i missed it..

I did put an aftermarket ignition system on my T500 though, but it was an optical system..  it was from newtronics or something like that, and i waited 8 MONTHS for them to come back into production.

Come to find out, the only difference from one to the other was the plate that the points mount to.. they were supposed to be specifically made points plates that held the optical sensor where they needed to go in place of the points.

well.. after 8 months of waiting and several hundred dollars to buy this thing, and shipping them from australia, i opened the package to find that they had basically cut a piece of sheet aluminum with tin snips, drilled and tap/die'd a few screw holes, and took a hand file to it where it needed markers..

I COULD HAVE DONE THAT MYSELF!!!!!!!!! IN FACT I COULD HAVE DONE A BETTER JOB OF IT!!!  the ******* things DIDN'T EVEN FIT!   nowhere close in fact....

but i figured, it doesn't matter.... i have tools, they did most of the work, i can finish it..

so i did.... i made the points plates fit, but still had trouble with the tiny bolts being too long, and i had to use spacers, which of course made the roatating assembly not fit through the optical sensors, so i had to fashion a spacer for the cam out of a washer and what not...

 it took me about 10 hours of work over a few days to make the stupid things fit...

basically, i could have easily bought the system 8 months before that, and used my STOCK points plates which i know fit, drilled, tapped and died the screw holes, and it would have worked flawlessly - had i known that this is the quality of crap they would give me...

so... i got everything mounted, the bike ran great, better than it had for a long time, but, i couldn't make it go faster than about 30mph.. it has something to do with the electronics part they gave me...  no matter what i did, it wouldn't work...  finally, at some point while adjusting the timing with the motor running, my screwdriver slipped, it caught the rotating plate, which flung it into one of the optical sensors, destroying the mounting ears and more or less rendering it completely USELESS after all of that work...

i was however able to fix it with bubble gum duct tape and bailing wire, but it still wouldn't run past 30mph..

i got pissed off, stripped all that crap off of there and bought brand new points and condensers from sudco, which of course didn't arrive......... so i had to call them back and have them ship me another set which did arrive... i was hoping that the other would eventually arrive so i could put them on my 125 but they haven't to date...

i put the points on there, tuned it up, adjusted it, and put about 250 miles on it over the course of about 3 nights with one of my friends who was the lucky bastard that got to ride my busa and leave me in the dust everywhere we went...  then of course for some reason the bike crapped out on my about 10 miles from home leaving us on the side of the road at about 2 in the morning.. fortunately it fired up and i was able to ride home at about 45mph and it ran just fine...   so we decided to park it, drain the crank case thinking it was flooded, and either go back out, or continue adjusting...  it turns out it wasn't flooded, so we didn't know what the deal was...

At a loss, we decided to prep and paint that bike...  we stripped the tail section and the tank, but it was too heavy to mess with after the first coat of gas, so we drained the gas out of it to find that the lining inside the fiberglass tank (by neuxstone on ebay) was dissolving, flaking, floating, and getting into my bike..  i checked the fuel filters and they were completely gummed up with crap.. (i use inline filters instead of in tank.) of course that crap went into my carbs and caused it to crap out on me and not run right...  

so, i emailed that dude about it asking what to do, and he said he would make me a new one until i showed him a pic.... once he saw the pic he accused me of putting "sea foam" in the tank which would cause that to happen, and since i did that he would repair it rather than making me a new one...  

honestly, i have HEARD of sea foam, but i have no idea what it does, or what it is...  and i have never -once- put anything at all in that tank aside from pump gas... no race gas, no high octane gas, no additives, no lead additive, nothing.... -nothing-  but he doesn't believe me....

Basically i'm out a $400 gas tank now. i did send it back to him.. we'll see if he builds me a new one, or if he tries to "repair" that tank..  i don't trust that a repair would be any better than what i sent him..  

i went ahead and bought a mid 70's style cb750 gas tank for that bike, and as we speak, i'm going through the Kreem process on my suzuki's original gas tank since i dont trust fiberglass tanks anymore...

i need to get the gas tank situation figured out and finalized though so i can figure out what to do about my tail sections..  

My friend says he will buy my glass tank for his 76 gt550, so i'm not at an entire loss.

Either way, now i have 4 non working bikes in my garage including my friend's triumph.  his bike is torn apart into about 500 pieces taking up space in my garage because he doesn't like to finish what he starts.. now he "doesn't feel like coming to get it today... "


so, my 500 doesn't run because of the gas tank, the 750, who knows.....  my 125 runs now that i put points on it, but smokes like crazy and has weird electrical issues that i have yet to figure out.. theres a ground somewhere and i cant find it... everything is brand new on the bike as far as wiring.. i don't know..

Thankfully my busa runs or i'd be out a vehicle.  i guess that's the good thing about newer bikes... they still run without having to mess with them every other day..

as for the 750 though, i still don't have much to say about it and won't until i get that point plate and plugs for it...

If it runs though, all i need is a chain and i can ride it around the block and such...

as eccentric as this may sound, i love it when ALL of my bikes run at the same time... i am test riding them all the time making adjustments, or riding them to keep the fluids from congealing, or, the batteries charged, or whatever...

 often times there are people sitting in their front lawns, and i'll ride by with a bike, then ride by with another bike, then another bike, and it always trips them out...  

with that said i'm probably going to sell the 125 and the 500.. which is why i'm trying to get it all figured out... if i do, then i'll have money to make my 750 like i want it....  

similar to carpy's koppa cafe...

only better....  no shortcuts on this bike... my others were meant to be rat racers. I'm gonna pull out all the stops on this 750 and give the fish a run for his money.... (if only because he told me the 78 doesn't make a good cafe racer).. well.... i'm not going to supercharge mine though..