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Yea i know she is old, but it's all i have. When i bought the bike it had a mid and top end splutter. I rebuilt the top end as i found that the previous owner ran it without an air filter. So i had it sleeved and a new piston installed. The splutter was there before the rebuild and it's still there after. I put new jets in it, but i just used the same sizes as was in it. Any way does anyone have the specs for this bike for the factory jet sizes, as well as the specs for the coil and stator ohm readings. Thanks so much, Bill

it's all there:
http://www.kdxrider.net/forums/viewtopic.php?t=1156
should work for any 2 strokes

Bikebandit says:
1980 KDX175 A1 - Pilot jet - 40, Main jet - 142.5
1980 KDX175 A2 - Pilot jet - 40, Main jet - 152.5, 155, 157.5, 160, 162.5
1980 KDX175 A3 - Pilot jet - #A20 (option)(?), Main jet - 152.5 - 162.5

Before you buy anything you might want to look and see what you have in there. You can try lowering the needle a notch or two, and/or opening up the air screw a little bit to see if the condition improves....
By the time you are done, you will probably be really good at getting your carb in and out! (the needle adjustment can sometimes be done by rotating the carb over in the boots, onto its side a little bit).

Coil and stator resistance specs will have to come from a manual, or from another "known good" part.

As far as the list of mains that were posted above, I got those off of a parts site as well. But they don't tell you the factory size for any given temp or altitude they just list all the sizes that were or could be used for tuning. I was hoping that some one out there might have a manual and could shed some light on the subject. The A1 A2 A3 is the factory codes for the year of the bike. A1=80 A2=81 A3=82 and so on. Jetting for the 1980 starts at 132.5, 135, 137.5, 140, 142.5 . The 81 and up has different jetting as well as the needle and slide are not the same as the 1980.I realy just need the baseline to start from. And i know that the coil specs will need to come from a manual, there again is the plea for some nice soul to help a guy out. Thanks and sorry for the long winded post, Bill

You start with the stock jetting and go from there... too lean... go up... too rich... go down.

No problem, Bill. But on BB, for the 1980 KDX175 A-1, the 142.5 Main jet is listed as (STD), and all the others are listed as options, so you may be well served to at least start with that one. The #40 pilot jet is listed as (option) but it is the only one listed, so, again, you would probably be best off to start there.
Sorry that I can not be of more help. It is kind of rare to find a KDX 175 of that vintage still running, I think.

No manual or parts fiche is going to tell you what jet to use at a certain altitude/temp. That is not a constant. You will only be able know what was standard in the bike when it was sold new, which will be the same anywhere. Two of the same bikes will sometimes be jetted slightly differently at the same altitude/temps. So you are going to have to just dig in and start experimenting to find what your bike likes.

Not to be rude, but i know that you would start stock and go from there. I need to know what stock is. As i said in my first post, I replaced the main and pilot with the same sizes as were in it. The pilot is a 40, and i feel that it is right as it starts great and idles great. But mid and top end just plain suck. And i can't remember what i put in it for the main. And the fact that we are in the middle of a cold snap i don't feel like pulling it apart. I looked at bike bandit, and see that 142.5 is std, that is nice as the site that i used did not give me that. It just gave a list of all jets used. As for the manual not giving you the jet sizes, if it is just a hokey owners manual it may not. All the books that i have ever had for my 25 years of riding sleds or bikes have allways given stock jetting sizes as well as some have given altitude chart. There are a few manuals on e-bay, but i refuse to buy from there as the price may be $xx.xx but with out a word of a lie, by the time you pay shipping to Canada, and get them acrost the border they will easily double if not more in price.

The jetting guide gives you symptoms and cures...

With your current jetting... you can figure it out from there. Jetting in a cold snap is not recommended. What is it going to get you?

The cold is only part of the problem. Even if i could get the bike started, -30*c or -22*f you would never ride because of the 3-4ft of snow on the ground.