175 Jetting

[Danny Poteet]

Does anyone know what the stock jetting was for the 1976 175 Penton?
Main, Needle Jet, Needle, and Needle position?


Blackbird Rider

[john durrill]

does your cylinder have 6 fins or 7? and what size Bing do you have?
John D.

[Danny Poteet]

John,

I don't know about the fins or the Bing.  I check this evening and get bact to you.

Thanks for the reply,

Danny

Blackbird Rider

[Danny Poteet]

John,

I check, my 175 has 7 fins on the cylinder barrel and the Bing carb has the number 84 cast into the body.  

Thanks again,

Danny

Blackbird Rider

[john durrill]

Danny,
 you should have another set of # on the carb somewhere, i'm guessing its a 30 mm.
main jet 150
needle jet 276
needle clip position 3 down from the top
pilot jet 30
 your oil to gas mix will change these setting some. Make sure you pipe is cleaned out ( burned out) the scilencer is cleaned out . your air filter in good shape and not too much oil on it.
 set the idle mix screw at 1 and 1/2 out and you should be at a very good starting point. get the bike hot ( at least 15 mins of running ) befor you try and adjust the mix screw and check the rest of the jetting out.
 if you can replace the needle jet with a new one. they wear  fast and will drive you nuts jetting if worn.
 Hope this was some help
 John D.

[Danny Poteet]

John,

Thanks, this should help.  I'm pretty sure that I don't have too much oil on the air filter.  But, I haven't cleaned out the spark arrestor, though I have been thinking that that could be my problem.  You're probably right about it being a 30mm, but I'll verify that before a proceed with the jetting.  Thanks again.

I don't want to make this too long a post,,,,, but, some background.  I purchased the bike new in 1976.  I actually traded in a 1994 100 Penton.  Years later I sold it to my brother.  He didn't maintain it very well and I bought it back from him several years ago.  I began a frame up restoration about 3 years ago.  And if I say so myself, (and I will), the bike looks very good today.  

Danny
Danny

Blackbird Rider

[john durrill]

make sure you burn the whole pipe out not just the endcap and replace the old fiberglass packing.
 the pipe has to be carboned up from wht you say .
 best of luck
JOhn D.