Need jetting help

Hey guys quick question here I bought 8ls 2002 Yamaha YZ 125 and It came with the incorrect carburetor it has a 28 mm carburetor so I went on eBay and purchased a 38 mm carburetor that was removed from up CR 250 my question is what jets do I need As far as I can tell the bike has a pro circuit exhaust and vforce reeds i live down in miami

You bought too much carburetor.  Sell it and buy a 32mm.

On 8/4/2017 at 2:58 PM, ccajigas07 said:

 

Hey guys quick question here I bought 8ls 2002 Yamaha YZ 125 and It came with the incorrect carburetor it has a 28 mm carburetor so I went on eBay and purchased a 38 mm carburetor that was removed from up CR 250 my question is what jets do I need As far as I can tell the bike has a pro circuit exhaust and vforce reeds i live down in miami

 

Ok,  it came off of a cr250.  Which model cr250?   cr250's came with mikunis and with Keihins depending on the year.   The 250's jetting is most likely too lean for your 125.  That means the needle,  the main jet,  the pilot jet,  and slide are very likely to be less than optimum for your application.   




Ok,  it came off of a cr250.  Which model cr250?   cr250's came with mikunis and with Keihins depending on the year.   The 250's jetting is most likely too lean for your 125.  That means the needle,  the main jet,  the pilot jet,  and slide are very likely to be less than optimum for your application.   
Its a mikuni tmx 38mm
Its a mikuni tmx 38mm
I pulp the actual needle no numbering was on it7e52c4e4e9a2445441d045c284e84792.jpg4b87bd6d665d0041c6acd1041340a33d.jpg997e2a01121dc4653ff475ac1e7ce2a7.jpg

can anyone help with this i already blew an engine and am currently rebuilding it and need to know what jets i need

looks like a 35 Pilot and 410 main ?

Needle should have number, too.

No visible number on it when i pulled it out only thing i can say is that the clip was in the middle setting what im trying to find out os what jets would i need for mine

I am seeing numbers on everything you put pictures up on so far.  Do you think you should see an eye specialist?

No eye specialist needed just someone who can differentiate cr250 jetting to yz125 jetting

Maybe, post up question in YZ125 forum to see if anyone has gotten a 125 to run well with a 38mm carby?

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