yz250 jetting

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primerib72
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yz250 jetting

Post by primerib72 »

I understand there are still a few yz250 2-strokers out there so just inquiring about your jetting settings for our altitude? Plan on breaking in the bike at wildrose whenever it opens but it would be nice to have a good baseline to start with and make adjustments while I am there.

Factory settings are 178 main and 50 pilot right now.

Thanks.
CR250R

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giantjoe
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Re: yz250 jetting

Post by giantjoe »

Congratulator! I'm afraid of how fast you're going to be... :eek:
----------------->just some guy<-----------------

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Re: yz250 jetting

Post by WR_Dave »

PM sent.
WR Dave
" Old Canadian Tire Supercycle 12 speed Mountain Bike " Good call Porschev !!

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primerib72
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Re: yz250 jetting

Post by primerib72 »

Thanks a bunch Dave....you da man!! :nworthy:
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Re: yz250 jetting

Post by dirtyboy »

So what jetting you gonna try PrimeRib? :confused:

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primerib72
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Re: yz250 jetting

Post by primerib72 »

Probably a 165 main and a 48 pilot just for the break in period then I will work from there. Dave gave me a good baseline but with the Eric Gorr porting and the 295 big bore kit it was suggested by him (Eric Gorr) to slightly raise the pilot and drop the main by one. I'll keep the needle in middle 3rd clip.
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dirtyboy
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Re: yz250 jetting

Post by dirtyboy »

Interesting. That sounds like a cool machine. I haven't heard of Eric Gore since I rode a yz250! I used his advice on my 91 yz250 and it worked out great.

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twotired
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Re: yz250 jetting

Post by twotired »

primerib72 wrote:Probably a 165 main and a 48 pilot just for the break in period then I will work from there. Dave gave me a good baseline but with the Eric Gorr porting and the 295 big bore kit it was suggested by him (Eric Gorr) to slightly raise the pilot and drop the main by one. I'll keep the needle in middle 3rd clip.
...break in period? Did you get a 2012? Where did you buy it?

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Re: yz250 jetting

Post by primerib72 »

dirtyboy wrote:Interesting. That sounds like a cool machine. I haven't heard of Eric Gore since I rode a yz250! I used his advice on my 91 yz250 and it worked out great.
The guy has been around for a long time now, he actually answers his phone an not some lacky. I went with a broad power band porting package, spreads the power throughout the rpms and almost eliminating the hit all together which is kind of strange for a 2 stroke. I guess I will find out. I offered Steve-o a rip and you are more than welcome to try it out.
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primerib72
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Re: yz250 jetting

Post by primerib72 »

twotired wrote:
primerib72 wrote:Probably a 165 main and a 48 pilot just for the break in period then I will work from there. Dave gave me a good baseline but with the Eric Gorr porting and the 295 big bore kit it was suggested by him (Eric Gorr) to slightly raise the pilot and drop the main by one. I'll keep the needle in middle 3rd clip.
...break in period? Did you get a 2012? Where did you buy it?
Yup she is a 2012, bought it at Blackfoot.....the only other one in the city is at Walt Healys.
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primerib72
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Re: yz250 jetting

Post by primerib72 »

Anyone interested in modifying their 250 2-strokes engines (and 4-strokes too) by Eric Gorr here is the link. Highy recommend this guy.

http://www.eric-gorr.com/
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Re: yz250 jetting

Post by timbruce »

I guess a formal congratulations is in order for you. Adding a new member to the Primerib family. Very exciting!! :cheers:

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Re: yz250 jetting

Post by primerib72 »

timbruce wrote:I guess a formal congratulations is in order for you. Adding a new member to the Primerib family. Very exciting!! :cheers:
Riding with all you guys made me realize I had to change to keep up.
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Re: yz250 jetting

Post by thirtyseven »

My heart is going all pitter-patter, will be a cool machine.
PRESIDENT-YAMAHA ANONYMOUS

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Rod
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Re: yz250 jetting

Post by Rod »

Congrats on the new machine!
'13 KTM 250 xc

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