I bought a 2006 YZ250, have ridden it 5 times.  It needs some tuning, but I am not sure I'm keeping it so don't want to spend much on it.

Has fmf gnarly expansion chamber and turbine core silencer.

I ride about 1000 feet above sea level.

I'm going to clean the carb and check the jetting.  What is a good jetting for me?  85 main jet?

Also check the reeds.  Is there a big difference between getting aftermarket reed cage and reeds or just getting a cheap aftermarket set of reeds that fit the stock cage ie.  Boyesen Power Reeds?

The other things I'm going to do is permatex all the joints in the exhaust system and a compression test.   It was 220psi 5 rides ago so I'm guessing itll be fine.  Its bogging a bit but I'm thinking its carb and definitely exhaust joint related.  

Let me know if I'm overlooking anything that could make the bike run crisper and more bottom end without throwing much money on parts

Your location indicates Canada, 

not yet quite warm here so if the carburetor has it's stock settings meant for 20°C / 70°F ambiant temps,

if ridden in 0°C / 10°C weather it will be a tad lean.

 

Before any attempts in fine tuning the jetting, make sure to adjust the float's level to spec.

 

Don't use Permatex / RTV around the reed cage but rather a gasoline resistant sealer like Motoseal or Yamabond.

Thanks.  Can I use the black permatex oil resistant gasket maker?  Its hard to find products in canada and everything is expensive.  If it's not at canadian tire, its going to be a pain in the ass

 Purmatex ultra gray is resistant to gas and other chemicals. Yamabond or hondabond would be my first choice tho

Canadian Tire does sell Permatex Motoseal.

 

Edited by mlatour

Should i use motoseal for all parts of the exhaust system or just that rubber joint? 

I've never found the need to RTV any exhaust joint myself, properly tuned a 2-stroke will not spooge.

There are already o-rings and rubber slip joints where required, just replace them if they're missing or damaged.

Edited by mlatour
16 hours ago, mlatour said:

I've never found the need to RTV any exhaust joint myself, properly tuned a 2-stroke will not spooge.

There are already o-rings and rubber slip joints where required, just replace them if they're missing or damaged.

My 4 stroke performs well when the exhaust joints are permatexed once or twice a season, why not a 2 stroke?  Im not sure Im keeping this bike, not wanting to spend money on o rings.  That rubber exhaust joint is $45 plus shipping OEM.

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