Bogging

**Blair.DRZ** · 24th March 2009, 11:10

My bike has got a bogging issue, when snapping the throttle on in 1st and 2nd, there is some serious bogging happening, I get that low tone and bike feels like its going to die, then let the throttle off again and she snaps back into life.
I've read up a little on this and looks as though its to do with the jetting, several people have installed JD Jet Kits and it fixes the problem, others have changed the leak jet and it makes it a bit better.
So anyone else out there with a WR that has had this problem and managed to fix it.
And does a JD Jet Kit ( or any other jet kit ) give more hp ?? Thinking that if I have to change the jetting might invest in some more power at the same time ( still running the stock exhaust).

**B0000M** · 24th March 2009, 13:44

its a 4 stroke thing, aparently it has something to do with the velocity of the air in the intake due to it only taking a puff every 4 strokes. i dont know about the yamahas but the hondas can be greatly improved by getting a jd jetting kit and making an adjustment to the fuel primer mechanism, however it can be improved with some find tuning of the air screw and jetting.

another thing that makes a huge difference on the hondas is binning the factory resctictive exaust and gettign something free flowing on there - in your case perhaps a yzf one - (i have no idea if these are interchangable)

**B0000M** · 24th March 2009, 13:44

oh, easiest fix is sell your 4 stroke and buy a 2 stroke

**B0000M** · 24th March 2009, 13:49

and as for performance increase, you might get a slight increase, but this is only because your bike will be running properly. the exaust will offer gains though

**Sammikins** · 24th March 2009, 13:58

my bike does that too.

**Blair.DRZ** · 24th March 2009, 14:05

Originally Posted by B0000M

oh, easiest fix is sell your 4 stroke and buy a 2 stroke

haha I should have expected that !!

only problem with the JD jet kit is that its gonna cost me some dollars.
May have to do more reading and get my head round how the whole jetting thing works ( I'm still learning as i go ).

**B0000M** · 24th March 2009, 14:25

i know nothing about yamaha's, is the WR engine the same as the YZ engine with just de tuned cam, exaust, intake, ingintion, jetting? if it is, the first thing to do to get some go out of it would be find standard yz parts on tardme for cheap

**Blair.DRZ** · 24th March 2009, 14:36

Originally Posted by B0000M

i know nothing about yamaha's, is the WR engine the same as the YZ engine with just de tuned cam, exaust, intake, ingintion, jetting? if it is, the first thing to do to get some go out of it would be find standard yz parts on tardme for cheap

Pretty much I think, I did the the grey wire mod ( changes the ignition mapping to a yzf ) and going to open up the airbox this weekend to get more air flow through it and check the throttle stop and shorten it to a yzf length.
Then if i can get this jetting sorted to get rid of the bogging i'll be a happy boy !!!

**B0000M** · 24th March 2009, 14:41

well if you do the yz exaust and yz cam, then just run yz jetting

sounds like a similar story i had on the mrs's crf250x, it originally had the massive bogging problem, every part i changed helped. did the airbox, the pink wire, the exaust, the cam and the jetting.

the difference it made is huge. the exaust was probably the biggest difference. i got one of those pro circuit 496's on there, so its not too noisy either... initially i stuck a standard crf-R one on it, but that lasted 1 ride before she destroyed it and a whole host of other bits in a crash