Boysen Quickshot?

[SeanOO13]

I have a 2006 450r. It is obviously very fast, but at low rpms when I punch the throttle it bogs and makes knocking sounds until it revs high enough. I heard that the Boysen Quickshot will eliminate the bogging. Is this true and is it worth buying?
Thanks for your help.

[GPracer2500]

Try a #50 leak jet (or thereabouts) first. The QuickShot is probably great for FCRs that don't have a tunable AP circuit. But your's does--the leak jet controls the size of the AP squirt. Leak jets work opposite most other jets. The smaller the number the more fuel get's squirted.

[ryann mx68]

that sounds more like you need to rejet it

[SeanOO13]

In response to ryann mx68, I don't think it needs to be rejeted. I have done no modifications to it yet and it has stock jets. It runs great. I am talking about hitting the gas at very low rpms.

I have never heard of a leak jet though. Are they only on FCR carbs?

[GPracer2500]

Only on current FCRs. They weren't in the original FCR models. It's located in the bottom of the float bowl. When the Accelerater Pump pumps, the gas goes two places--1) out the AP squirter in the venturi and 2) through the leak jet into the float bowl. The leak jet basically bleeds fuel from the AP squirt. The larger the jet the more fuel gets bled off and the smaller the AP squirt.

The AP is there to deal with the carburetor deficiency you are most likely experiencing. When the throttle get's whacked open from low rpm, the vacuum in the venturi changes quickly. The pressure signal that pulls fuel through the jets gets momentarily out of whack. The result is a temporary lean condition that persists until the carb's pressure signals normalize and flow fuel normally. The AP mechanically (so its function is independent of vacuum) squirts raw fuel into the engine to compensate for the temporary lean condition. APs work but they have to be tuned to be at their best.

[Flyin-Low]

You know WAYY too much about this stuff... :rolleyes:

:blah:

[d3ktrix]

You sure you’re not just in too high of a gear when you punch it making the engine lug?

The bog most people complain about is different then what you are describing.

we have one, havent put it on yet, ill do a full review when we get it on :macho

[Lonestar_R]

GP Racer knows what he is talking about........save your 80 bucks and go buy a 5 or 6 dollar leak jet.......and your bogging problem will be gone....I have a 42 in mine, stock is a 70......this will help.....I rode my buddies a couple weeks ago and his is bone stock...and it bogs when I ride it like I ride mine......the 06's are very corked up and are jeted way lean from the factory.....they still will knock and make noise when you lugg it at low speeds but that is beacuse Honda geared them high ......first gear should of been at least 2nd...if not 3rd......I never rode an 04-05 I guess they were worse yet......I hope this helps you out......

Originally posted by Lonestar_R
GP Racer knows what he is talking about........save your 80 bucks and go buy a 5 or 6 dollar leak jet.......and your bogging problem will be gone....I have a 42 in mine, stock is a 70......this will help.....I rode my buddies a couple weeks ago and his is bone stock...and it bogs when I ride it like I ride mine......the 06's are very corked up and are jeted way lean from the factory.....they still will knock and make noise when you lugg it at low speeds but that is beacuse Honda geared them high ......first gear should of been at least 2nd...if not 3rd......I never rode an 04-05 I guess they were worse yet......I hope this helps you out......

ya i kno he does, but this is on a 400ex fcr carb i bought about 2 years ago or so, it doesnt have the same stuff as the 06 450 carbs or i would rejet

[Lonestar_R]

ok I agree Yurik...what I stated is only good for the newer FCR carbs......

[atvwdsrcer]

before you spend any money turn your idle up! That alone should stop your problem. If not try the leak jet. I have been using the quick shot for a few months now and yes it does increase the low end response, but for $80. I would try the other solutions first.

[repsol/honda]

does anybody have any suggestions on how to fix the same problem on an o4? mine does the same thing. i ride at 9000ft so its jetted for that, i have a hrc end cap and that all.
thanks

[repsol/honda]

does anybody have any suggestions on how to fix the same problem on an o4? mine does the same thing. i ride at 9000ft so its jetted for that, i have a hrc end cap and that all.
thanks

[GPracer2500]

Originally posted by repsol/honda
does anybody have any suggestions on how to fix the same problem on an o4? mine does the same thing. i ride at 9000ft so its jetted for that, i have a hrc end cap and that all.
thanks

First thing I'd do is confirm your pilot circuit is correct and (like atvwdsrcer said) turn up the idle a little. The pilot circuit should be tuned regardless. But if a carb doesn't have an easily tunable AP then turning up the idle usually helps--sometimes a lot.

If nothing helps, then there ARE ways to tune a AP that doesn't have a leak jet. But you're venturing into territory few have been so you'll likely be on your own for figuring out how to adjust the pump squirt timing and duration. This can involve adding a pump cam stop screw and/or switching to a different AP diaphram and perhaps other methods.

[Lonestar_R]

I didn't adjust the circuit...after I installed the 42 leak jet it was almost perfect.....if the circuit is not adjusted correctly the squirt will hit the back of the slide when the throttle is stabbed.....I did not have this problem when I put my new leak jet in.....you can jam the throttle wide open on mine and it never misses a beat....

[moogie66]

Where can we get these leakjets from, Is it Honda part or elsewhere, i mean #42 or diffrent sizes than std

[ryann mx68]

the parts are not listed under the 450r carb

pull up the [06 CRF 450 carb], all the jets are listed under this

leak jets, pilots, crf needle, etc

[Lonestar_R]

I got my leak jet from www.magicracing.com 42 was the smallest they listed I figured I would start there...it is seemed to have worked

[repsol/honda]

thanks for the info gp racer. i am currently in iraq but when i get home i wil try that.

[st8jacket]

GPRacer,you know your stuff,I'll tell ya...Ive been reading alot of your posts and your allways on track with the correct answers and not leading people astray,like some do..Even if they are thinking it is correct...Its good to see another wrencher that knows his shizzit....:) :)