Tuning advice requested.

[CWilson]

Greetings to all and what a great forum!  I am the original owner of a 1975 125cc Penton enduro.  It has 1538 miles on the odometer and I am currently trying to get it running properly.  Prior to a few days ago it hadn't been started since 1994.  Here is what's going on.  With all carb (Bing) passages and jets clear, clean air filter, fresh spark plug and air screw 11/2 turns out the engine doesn't run well at all from idle to 1/2 throttle.  From 1/2 to full throttle she screams.  After a couple of minutes of blipping the throttle to keep the revs up I shut her down and took a plug reading. The plug was wet(rich?).  For no particular reason I wonder if the crank seal on the mag side might be leaking. Please advise.        Thanks Craig Wilson

Craig Wilson

[Larry Perkins]

Craig,

There are a couple of possibilities.  It is quite possible the crank seal is leaking as this is common with bikes that have sat and were not run.  It is probably not on the mag side though it is most likely on the clutch side.  When the mag one leaks it runs lean and an erratic higer idle is generally present.  If it is leaking on the clutch side it will smoke too much.  Another thing I see in alot of old Pentons with Bing carbs is the slide and needle jet are worn and down low the throttle response is bad.  If the slide is too worn it will have a good smiley face worn into it.  Just replace the needle jet if it has been awhile as over time with useage they ovalize on the Bing.  So what once was a 273 is now way bigger.  Good luck and welcome back to Pentonia.

 

[john durrill]

Craig,
 did you get the bike running right?
let us know one way or the other. the more info you feed the forum the more specific the answers we can give. Did you burn out the pipe?
 Thats a biggie on all 2 strokes.
John & Peter

 

[CWilson]

John, my Penton is up and running crisp and strong!  The idle jet which I thought was free and clear was partially blocked with some debris.  After clearing the blockage and making several high speed runs she cleaned out and runs fine.  I am going to purchase some fork seals from Larry Perkins and replace the rear shocks.  I am also in the process of making the bike street legal so that I can ride to some nearby trails.  With street legality in mind is there a method by which someone can wire a battery into the electrical system so that lights can work without the engine running?
Also are Konis shocks still available?  
Thanks.

Craig Wilson