Bigger start jet. Is there a downside?

Gidday to all the WR450 jetting guru's.I am thinking of going up to a #72 starter jet on my aussie 04 wr450. It now takes a few more kicks to get it started when cold, now the temperature is dropping. It used to be first kick (or push of the e/start)

Is there a downside to going too big on this jet. I am aware that it controls the choke circuit only, but was wondering what would be the symptoms of it being too rich.

FYI, I run a full FMF exhaust system, 170MJ, 48PJ, #40leak jet and F/S 2 & 3/4 turns out.


No down side , just easier starting when cold.I was only able to get a 70 as i was told yamaha australia didn't bring a 72 in ?

Thanks for the info, fellow aussie :)

Anybody know what the stock starter jet is on an '05 WR450 is?

Thanks for the info, Jeff

the stock starter jet is a # 65

the stock starter jet fore the 05 yz is a # 72

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now