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New to 2-strokes. Cr80 questions.

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Well I have had this bike for about 3 months now and I have some questions. It has a full FMF exhaust and a uni filter. Are you suppose to jet it because right now it is jetted as stock 125 main and 3rd needle position? Is the plug suppose to be black a little bit? It is black on the tip but I can see some white if I look down the plug. Sorry for the long post.

Thanks Jason.

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Call FMF and asked them for the jetting specs for your YR/model..

They should be able to help you.

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The FMF website says to have a 122 main and a 55 pilot. Thats leaner than stock though so I guess I will leave the 125 main in. Do two strokes usually have any carbon build up in the combustion chamber? I pulled my head off to replace the leaking head gasket and there was no carbon on the combustion chamber and very little on the top of the piston. Sorry for the long post.

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it could be running a little rich if it is black and that little white thing down the the plug is the electrode and all plugs and them iam pretty sure but these other guys on here maybe able to help you a little better

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Sounds like you're ok. A little black on everything in there (combustion chamber) is normal. You said there's no major carbon build up and you can see some white on the plug insulator down in. That all sounds normal to me. We have a CR85 with a FMF fatty and silencer on it. Left the jetting stock. Never fouls plugs and runs tops. Sorry for the long post. ? Is there a three line limit?

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Ok. Thanks for your help. I am just used to posting somewhere else with a smaller posting area and three lines looks alot longer there.

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Kurly, seeing you're new to 2-strokes, let an old 2-smoke guy give you a tip. Long ago, I started wearing a small fanny pack with a spark plug wrench and a plug wrapped in a rag (now I put my phone in there too). Everytime I think it's a waste cuz my bikes just don't foul plugs anymore I'll lose a plug. It sounds like your bike is jetted pretty well but eventually when it just won't stary, always try a new plug first - and if you're on the trail, you'll be glad for the fanny pack.

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Thanks for the tip redferver. I only trail ride, no tracks close enough to me. So far I love the Cr80. It just loves to pull the wheel up in third gear. How do you go about replacing the fork seals and what kind of fluid do you put in them after you replace the seals? And I just replaced the head gasket because it was leaking and now it seems like it is blowing more smoke now? I am running 40:1 with Spectro 2-stroke oil and 93 octane gas.

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I'm gonna get creamed for admitting this but when either fork starts leaking, I wash the bike, pull the forks off and run them by my local shop to have the seals and oil replaced. (Replacing seals was pretty easy but ever since cartridge forks I gave up as it takes too much time and supposedly needs special tools, etc.)

If you can't afford paying for the labor, buy the shop manual, seals and the correct amount and weight of fork oil (mine uses 5 weight but the manual will specify for your 80) and ask your local shop(s) for advice.

Don't know about the head gasket, replacing it shouldn't make the bike smoke more - hopefully it's just a coincidence.

Good luck!

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Is there any way to put the seals in without any special tools? I just don't have the money to take them to a shop.

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Well it sure isn't hard putting the seals in - you just pry the old ones out (careful of the metal behind) and oil the sides of the new ones and tap them into place lightly with a rubber mallet then finish the job with an upside-down socket of the appropriate size until they're "seated." (Some people cool the seals in the frig and heat the fork leg slightly to make them go in easier but I've never had to do that.)

The problem is getting the fork apart and back together perfectly as they're important safety components (versus rebuilding a kick-starter, etc). Depending on how old your bike is the job may be a bit easier than my newer models but, even on my old bikes, I've always had to at least use a power impact driver to get the fork leg separated from the internals.

Like I said; with a shop manual, some advice and a clean working area it's definitely doable but forks are a bit more involved than people tend to think. (Wouldn't hurt if a mechanically-inclined Dad or Uncle was around so you could borrow their tools and bug them with questions.)

Good luck!

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Ok thanks for the tip. I would need someone there with me because I have never took forks apart before.

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How does one go about stiffening up the rear shock? If you hit a bump on mine it just bounces. About how much would it cost to send it out to get set up for my weight?

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