i had installed that radiator hose to my airbox on the 650 to increase the air inlet diameter. now when i gun it from a stop it doesnt pull as hard untill it catches some speed then it accelerates like before. sorta like it hits a powerband, which it never did before. do i have to rejet, i didnt remember the guys who put this on having to rejet.

 

what diameter is the hose. and if you increased the amount of air your bike takes in you need to rejet. unless you use the same diameter hose

 

<div class="FTQUOTE"><begin quote>Originally posted by: frndinalowplace

i had installed that radiator hose to my airbox on the 650 to increase the air inlet diameter. now when i gun it from a stop it doesnt pull as hard untill it catches some speed then it accelerates like before. sorta like it hits a powerband, which it never did before. do i have to rejet, i didnt remember the guys who put this on having to rejet.</end quote></div>

Jets are cheap, about $2.00 each. The way that you find out if you need to rejet is to do a few WOT (wide open throttle) test with a new spark plug.
Warm your engine up with an old spark plug and then when you get ready to do the test then change and put the new plug in. Start your engine and as soon as possible go to WOT and when you reach the top speed cut the ignition and slip it in neutral, bring your machine to a stop and do a spark plug reading.
The key is not to have the engine idle and influence the spark plug color.
A sort of short cut is to bring the engine to top speed and then start to apply the choke if it increases in speed or smooths out then you need a bigger jet. If it bogs then you need a smaller jet or more air.
Part of the reason that your engine doesn't accelerate properly is the air/fuel mix at the low end. A simple adjustment under the carb. This is the adjustment for idle and up to about 1/4 throttle until the main jets take over. Your main jets take over at about 1/4 throttle until that point you are running on the pilot system. The air/fuel mix adjustment is NOT the speed adjustment, although that may need to be adjusted also.

 

hey buck, where is that adjustment screw located? its not the same screw that is on the cable to adjust idle right? excuse my lack of knowledge on carbs, never really worked with them, ive torn my monte carlo motor apart plenty of times and know how to tune via my laptop.

 

not to step on your toes buckaroo or to say your any less knowledgable . but there is a guy on arcticchat.com his name is wyo-cat this guy is rediculousely knowledgable withg carb. he is the unltimate carb guru. also there is a pinned section on there about jetting which describes the process in which buckaroo is explaining in detail. you can also print it out so you can do it step by step

 

<div class="FTQUOTE"><begin quote>Originally posted by: frndinalowplace

hey buck, where is that adjustment screw located? its not the same screw that is on the cable to adjust idle right? excuse my lack of knowledge on carbs, never really worked with them, ive torn my monte carlo motor apart plenty of times and know how to tune via my laptop.</end quote></div>

Download this manual, it may help you out. It may not be for your year of machine but the principles and most everything will be close. You can look at the carb section and see where everything is located.

http://silentfall.com/files/manual.zip

 

<div class="FTQUOTE"><begin quote>Originally posted by: frndinalowplace

hey buck, where is that adjustment screw located? its not the same screw that is on the cable to adjust idle right? excuse my lack of knowledge on carbs, never really worked with them, ive torn my monte carlo motor apart plenty of times and know how to tune via my laptop.</end quote></div>

You can get a ton of information at this link. Many Q&A.

http://www.dfn.com/benkaren/jetfaq.html

 

For the first time carb tuner I highly suggest buying a Dynojet kit. You get a variety of jets as well as adjustable needles that you will need to adjust the midrange. That radiator hose makes a HUGE difference on that 650 and you will need to make major adjustments.

 

see i heard there was no need to rejet with just the radiator hose mod, crap, well im replacing the snorkel back to stock until i get a jet kit. i bought a dynatek cdi, and am gonna buy a k&n filter as well for it, so ill just wait to rejet until everything gets on there. thanks guys!

 

If I remember correctly the radiator hose lets in around 27% more air, which is obviously enough to need the rejet. I still recommend the kit, you will need to adjust your needles and the stock ones are fixed.