mini buffalo (chibi engine) starting probs

[hmmmnz]

well guys, i have rebuilt the wee engine. i'd like to say to its former glory, but its a bit of a mix and match of parts, ts50er conrod, machined crank pin, pa50 rings, home made gaskets and a pant load of bearings,
i have the beasty back together and have it freely turning over, with decent compression, a decent spark (outside the engine anyway) fuel to the carb,  but she's not wanting to start, not even a cough,
even with start ya bastard
its the original plug from 1973.. may be i should get a new one?? even though its sparking.

any clues, timing is fixed and stator has gone back the same place it came apart, same as the rotary disc,

very frustrating i tells ya, i thought the hardest bit was trying to find suitable parts...
aparently not |:D

[Dave K]

Well, you know the old saying. If there is enough compression and fuel and spark at the right time, it will run. I would start with spark. If nothing else, dial an AM radio and watch the timing mark as you bring the flywheel around and listen for the "click" when the timing mark passes the mark on the case. If it does make that click, you at least are close enough to run. Then, I would try fuel. Again, just give it a little blast of either, just to see if it will run that for a few firings. If it does, then you can look to the fuel delivery. Again, this is all concerning that there is enough compression. JMHO

[hmmmnz]

im not sure i understand the am radio reference, but ill check the timing and replace the plug.

it cant be the compression, new rings anda sweet bore,
hopefully its that damn plug

cheers for the help

[Dave K]

It was an old trick when I was a kid and these bikes were new. When you are on an "off" station on AM, you can hear the points as they break open. On the radio, you will hear and audible "click". So you can watch the timing marks and hear the points open.

[hmmmnz]

wow thats cool,  i cant say ive seen a am radio in years though
ive watched the points as i turn over the motor, and it appears that they open and close as its saposed to

[old smokey]

Last summer I had a weed eater die on me when adjusting the idle speed. Pulled my arm sore on that thing. Later I pulled the plug and saw a somewhat yellowish spark. After more trying I switched plugs and then saw a blue spark - so "any" spark is not always a good spark. Another thing I like to do for hard starting engines is the use of model airplane fuel. I have an old container of 15% nitro used for glo-plug engines. If an engine won't start with that, then it needs more fixing. Otherwise, the glo-plug fuel has castor oil in it so it lubricates a 2 stroker when you shoot it into the carb or cylinder. Not to mention the sweet childhood memories of smelling it burn!

[jaynave]

Ha!
   Lots of good stuff here.  First,  get a new plug so that you get a blueish/white spark.  I can't tell you how many hours I  kicked over my old 100 Sport.  Apparently the stator/ignition  windings were defective but as an eager teenager, I figured if  it sparked outside the  cylinder, the ignition  was OK.  I  could get it to  run  with  a fresh charge on the battery but eventually it wouldn't start.  I'd pull the plug, see a yellow spark and kick  till I was out of breath.  The weak/yellow spark can get snuffed out by  compression and make for a hard starting engine which of course is by now flooded as well.  Do what you  gotta do to get a clean bright  white spark.  Once you  get there, it   should go.
    Model Airplane fuel?  Back in the  day (73), I had saved my money and had purchased the  parts from some new supplier (Yoshimura) in CA to  rebuild my CB 350.  I  had the pistons, CR carbs, a cam and 'racing' valve guides and springs.  Before I sent the  head away  for their port and polish I bought a gallon of Fox Missile Mist ... 35% nitro  I  think.  I remember it was over 30 dollars.  I poured that in  my CB 350 gas tank, pulled the stock air cleaner and put on velocity  stacks from Racecrafter's with my mom's nylon stockings cut to fit for filtration, held in place with  rubber bands around the velocity stacks.  It wouldn't even  start!  I  added a gallon  of gas to dilute the model airplane fuel and it  started but didn't  want to  idle.  No  problem,  I wasn't interested in the idle anyway.  When I took it out, it  would hardly  run till you opened it up- then  it took off like it never had before.  I got it up  to 70 or so and heard a phoomph and slowed down to  see what had  happened.  The nylon stocking  air filters had  both  been  sucked into the   engine.  An expensive experiment...  Even after the rebuild with  Yoshimura 342cc high  compression (215 psi !)  pistons, the  CR carbs, port and polish, it would still only  run 14.70.  I  was just now running with  the  stock Yamaha  350's at the  drag strip on the weekends. 
Good grief!!

[Bridgestone Man]

Jay  What a neat story, bring back memories too, me as a kid, I had a BIG bike, a Honda CL250, there was this kid down the street who had this little
crappy Bridgestone 175. I could not figure out why this little bike could outrun my Honda anytime, anywhere.  It took me a while to figure out that two
cycles machines were fast, only later did I learn that Bridgestone 175's were about the fastest of the small twins.  What an education..  Sam

[hmmmnz]

well i had a bright blue spark on my old plug, but bought a new plug today, and still no joy,
it doesnt seem to be flooding the plug seems dry when i pull it out,
the carb is clean, and i beleive the rotary valve is in the right place, (going by the mark i put on when i dissasembled, and the mark that was already on the valve) i can't beleive i put that together wrong, but it is a possibility i suppose , (ive never worked with rotary valve smokeys before)
i am truely miffed, its been a many moon since i worked on a smokey, as i usually have 4 strokes, but im sure i didnt get it that far wrong...
but we all know what thought thought..... though thought wrong


any more pearls??

[Bridgestone Man]

Maybe a long shot, but I think it sounds like your crank seal is not sealed up, either at gasket area or
the two dreaded crank seals.     

[hmmmnz]

crank seal??? it only had one



i made a new gasket seal and everything is nice and tight

do i need a seal under the little cog??

[hmmmnz]

well i have finally managed to get it running!!!!! 33 years since she was last started and on the second kick
she was away and purring


my problem....  was the gap on the rings was too much,

i managed to get a set of rings from..... a husky 45 chainsaw, of all things
im so stoked!!!
ill post a video of her running.... when i figure out how to do that



happy new years