Getting closer

[V1346]

Here is where I am at.  I bought this 69 125 ISDT bike last year and it had not run for over 30 years.  I have freed up the engine which had a seized piston and have good compression.  The carb has been cleaned totally and a new float installed to replace the float which was filling with fuel, no kidding.  I set the float so it is parallel with the bowl flange per the manual.  The bike still has points ignition and there is a good spark.  The timing looks good by eye.  New plug installed. I am running the fuel using lawnboy oil mixed at the recommended 32:1 ratio.
There is fuel getting to the cylinder, the plug is wet.

So why won't the bike run?  Any obvious things I am missing?  I've got the mixture and idle screws at 1.75 turns out. Do I need to dump the fuel and make up a new batch using motorcycle 2 stroke oil?  What ratio should I use.  Spring is here and I'm getting anxious.  I'm in Newark DE if anyone wants to come by and give me a hand, I'll buy the beer.

Bill

[Lew Mayer]

I'm not far. In Stewartstown PA. Run on over if ya need to.

Lew Mayer

[slvrbrdfxr]

Bill,
Sounds like there is good possibility that the bike should run but I have a few questions. By freeing up the engine does that mean you had the top end off and bored the cylinder and installed a new piston ?? If not, then once it was freed up, did you check the compression with a gauge to be sure exactly what you had ?? Did you remove the exhaust pipe and check to be sure it wasn't plugged up with a mouse or mud dobber nest ?? Might be a good idea to confirm the timing is correct also using a timing gauge. If you have the flywheel off take a close look at the crankshaft seal to be sure it's still intact also.
Dave McCullough

[V1346]

New piston.  100 psi on compression, is that OK.  The exhaust is clear.  I'm off to radio shack to get the makings of an ignition buzzer to check the timing.  Is the 1.75 turns on the carb a good starting point?

[paul]

Hey Bill, do you have another carb that you could use that you know is good? (if not I have a 32 you can try) I ran into a similar incident last year on two seperate scoots. Both times I was beating my head against the wall as the bikes should have run. Plug was wet, spark, compression...everything as it should have been. Finally I got the idea to swap the carbs with one I knew worked good and Bam, both the Hare Scrambler and Maico started on the first kick after replacing the carb. I have no less the 5 Bings in a box that I cant figure out what is wrong. A friend said the slides where out.
 Before replacing anything I would try to bump start it as maybe its just loaded up. My take, Happy Easter,TooTallPaul

[t20sl]

Bill:
   You might also have a lower crank seal(s) dry rotted and letting air into crankcase.  After 30 years I would replace both left and right seals before relying on bike to continue to run.

[V1346]

Success--- sort of.

I managed to get the bike running but it is way too lean.  I can keep it going by placing my hand over the carb throat.  As the bike warms it seems to get better but it is not good and will not idle.  I guess my next step is to replace the crank seals.  Anything else I need/should  do while I'm tearing into the motor?

[thrownchain]

Before you do a tear down, find someone to do a pressure test. That way you can determine whats leaking. I say that because alot of the symtems you desribe could be a plugged carb also.

[V1346]

I kept cleaning and blowing air through the carb and the bike seemed to be responding.  Finally today I got it going.  The net result is I woke up a Penton owner and I am now a Penton rider:D

[tomale]

those 30 year old seals worry me,, even if they are working now does not mean that they will work for long... not trying to scare you... well actually I hope I did.... Seriously, anything like that, seals and other rubber parts do not hold up well over time.... they continue to dry out.... continuous use will actually prolong the life span. but having a motor that has not been turn over in 30 years is not a good thing... do you self a favor, replace the seals at your earlest convienence... by not doing so you could ruin that motor and it would cost you a lot of money to get going again...

Thom Green,Still crazy after all these years!
76' 250 MC5 (orginal owner)74'
250 hare scrambler (project bike)
72'sixday (project bike)

[V1346]

Now that the bike is officially a runner I will be ordering a bunch of stuff for the big finish.  I'll add the crank seals to the list.  Thanks for the advice.

Bill

[PJM]

So, what did you do to make it finally run?

PJM

[V1346]

Kept cleaning the carb with solvent and air. Pulled the jets and soaked them, blew out passages, etc.  Must have had the carb off a dozen times.  Each time it got a bit better. Also I think running the bike with my hand choking the intake and running gas through it was a big help.  Finally it was a 1 kick bike, even cold.  I couldn't believe it.