Accelerator Pump/ Leak Jet Questions

My bike has been fairly boggy lately and i have been researching some options for making my bike snappier i think i have found the solution, or rather solutions.

-go a size smaller on the leak jet- hopefully that will work if not i will have to take off the float bowl and change the jet again which isnt a huge deal its just a pain in the ass on the aluminium framed WR's.

- or i could buy an aftermarket AP cover like a boysen quick shot or merge racing cover with the adjustable leak jet looking on boysens web site there are alot of claims that the quickshot works wonders. so i was just wondering what some of your guys's opinions are and if these aftermarket cover work well and are worth the price


I would go with the adjustable cover. Just turn a screw to control the acclerator pump volume. There's nothing wrong with changing the leak jet, but as you eluded to, it's a pain.

I have a BONE STOCK 08 WR450. Does the adjustable leak jet come come with some sort of table that shows Example, 40 leak jet is equivalent to 2 turns out, 50 is 3 turns etc etc? maybe not those exact numbers but something that shows a certain leak jet is equivalent to X number of turns?


Would like to get one but don't want to install and not know what the base setting is.



I am sure the part comes with a "Base setting " and then you ride the bike and go from there.

not too hard to figure out.

That's considering the Bog is coming from the accel circuit.

If the bike was fine and now is not, that is not considered a jettign issue, rather it is a service issue.


Nearly all 450's do not have a leak jet, so an adjustable one added on will not make it better (infact, probably make it worse).


Ensure you have a good squirt from the AP. Make sure the linkage moves slowly. Check the check valve. The squirt from the pump shoul be like that from a super soaker.



There is a write up I did about 'the bog' in the WR450 FAQ section.

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