Boyesyn quick shot accelerator pump cover GOOD OR BAD!!

15 replies to this topic
  • fastwr450f

Posted June 01, 2006 - 07:31 PM


I have a 04 wr 450 that bogs when you snap the throttle, it has white bros. carbon pro 1, pipe and header, dyno jet stage one jetting kit, ALL the mods, I have it jetted to dyno jets specs, I do run 100 octane race gas. but I can not seem to get rid of the bog when I SNAP the throttle. Will the quick shot help??????????????????????????????????


Posted June 01, 2006 - 08:20 PM


I put one in and it helped but did not eliminate the bog from idle. Mine only bogs in neutral with a fast snap of the throttle. It doesn't do it under load. I noticed the biggest difference in 1/4 to 3/4 throttle to wide open. It crispened up that range the most. Not a huge amount but enough to notice.

Hope this helps

  • RC81

Posted June 01, 2006 - 11:03 PM


I put one on my 05 and have no bog. I have re-jetted it but never messed with the pump timing or anything else. Put it on when new so I never even rode it without it - don't know if there was a bog before.

  • ARin

Posted June 01, 2006 - 11:20 PM


#40, #30 leak jet.

try that, and come back if that doesnt help or fix it.

  • Matty05

Posted June 02, 2006 - 04:39 AM


#40, #30 leak jet.

try that, and come back if that doesnt help or fix it.

:applause: As well as correct tuning of the pilot circuit.

  • bg10459

Posted June 02, 2006 - 04:50 AM


:applause: As well as correct tuning of the pilot circuit.

True, true. The quickshot is no quick fix. Just about every benefit of it can be achieved through proper jetting. Dial in the carb first.

  • odonnks

Posted June 03, 2006 - 02:30 AM


I installed one just to see if there were a difference. My bike was jetted well and barely had a droop off idle. The QS helped some but I'd say it was more in the 1/8 to 1/4 or 1/2 range. It chrispened it up and I thought it was already chrisp.
I agree with the above suggestion to reduce the leak jet size. I went to a #35. That and adjusting the AP linkage helped the most I think.

Worth the 80 or 90 $$ Hard to say. I'd rather have put that toward a Vortex CDI. I sometimes ride in verrrrrryyy slippery conditions and hear the traction map works great.

  • MountainMax

Posted June 04, 2006 - 04:54 AM


I bought mine on ebay for a reduced price, and put it on when i jetted my carb after doing the free type mods and muffler mods so i can't say if that one thing made much of a difference, but in theory it should work.. :applause:

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Posted June 04, 2006 - 05:47 PM


I haven't heard anything great about the quickshot. I know some guys who put them on quads. Most of the Yamaha guys worked with the leak jet to get theirs right. The rest didn't do anything.

  • StreetbikePimp

Posted June 05, 2006 - 08:27 AM


Flip a coin and take a guess on whether or not it will help you.

There are 5 things that can be adjusted to affect the bog.

1) the Boysen cover (which reduce the volume of gas in the squirt)
2) the leak jet (which also affects the volume of gas in the squirt)
3) the Accelerator Pump screw (affects the duration of the squirt)
4) the pilot jet.
5) the pilot jet air screw.

If you have the WR450 manual, study the section on tuning your carb. It's good information and will teach you a lot before you waste a $100.

  • bandit99

Posted June 05, 2006 - 12:58 PM


I thought the Boysen eliminated most of the air associated with the stock Accelerator pump. The stock one injects more air which causes the bog. I could be wrong though. Maybe someone can shed some light.

  • Matty05

Posted June 05, 2006 - 04:52 PM


I thought the Boysen eliminated most of the air associated with the stock Accelerator pump. The stock one injects more air which causes the bog. I could be wrong though. Maybe someone can shed some light.

First of all, how would you get air in the fuel circuit?

What the boyesen does is fill up with fuel quicker and deliver a full squirt of fuel.
Accelerator pump only works when you turn the throttle.

I can only see the boyesen of benefit if you are on and off the throttle every second.

  • dirtysouth

Posted June 05, 2006 - 06:17 PM


I am with matty. The Boyesen isn't worth all that much unless you are superXing or the like. I just installed a jet kit on my 05 and there was an O-ring in the kit with instructions on what to do with it. This Redbeard guy has a link with some info on how to do it this way and also do it with safety wire.
Redbeards carb stuff

Either way...I did it to mine today and bye bye bog of the bottom... :applause: Basically you just tighten up the AP response.

BTW..remember this is a four stroke so the two-smoke crispy response will never be equaled unless you supercharge that 4 cycle beast. But even still, we're talking about one cylinder that may be on the intake stroke when you want power now... :D

  • 642MX

Posted June 05, 2006 - 08:06 PM


The Quick Shot works as advertised. Its no cure for crappy jetting or a misadjusted fuel screw, but when your jetting is close and your fuel screw is set properly there is a big difference in the throttle response with the cover. I think it works very well and its worth the $89.

  • rtrolli69

Posted June 05, 2006 - 08:15 PM


Well let me chime in...personally I have an 05 wr450 it didnt have any bog after re jetting.all free mods,Dr D pipe,pwr plus bike ran great!!My brother has a 03 WR450 we checked leak jets mine was correct factory his wasnt.His bike had a bog at idle or riding.he changed leak jets fixed his!!!!I read an article about quickshot helping your bottom end and making more crisp!!So i spent the80-90$$$$I felt no difference in made my bike a little harder to start with the button???So No in my book check Indys jet chart and change leak jet,save the $$ and put on the pwr plus its worth it!! Russ

  • wr450fwi

Posted August 23, 2009 - 06:56 PM


hi guys i read this thread and i have a question for y all who buy the quickshot and those who buy leak jet .what is the diference between buyin a quick shot or just changin the leak jet to a size like 30 or 40 .
the quickshot ain t suppose to have an adjustable leak jets


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