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Pretty good article on carb removal and how-to-jet for a KLX450r

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I ran across this article in an old Dirt Bike magazine(July 2008) the other day and it helped me install new jets and needle in the bike.

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img2286h.jpg

If you want a better copy, PM and I can email you a bigger pic. I searched online to try and post a link, but it is not out there.

I put in a 165 main, 48 pilot, shimmed the stock needle with 2 small lock washers, fuel screw 1 1/2 turns out and did the o ring mod. This combo was going on a bike with a Leo Vince full exhaust system, also the snorkel and AIS removed.

Hope it helps!! :banana:

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Need some help with my 450. I just bought a BRAND NEW 2008 klx450r and after reading some post decided to do some of the simple mods. I removed the snorkel and installed a new 165 main jet but when I looked at the needle there was no notches to move it to. So I put the bike back together and now im having an issue with it hesitation when I first crack twist the throttle. Can anyone help me with this?? Suggestions on what might be causing this or what I can do to fix it??

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Need some help with my 450. I just bought a BRAND NEW 2008 klx450r and after reading some post decided to do some of the simple mods. I removed the snorkel and installed a new 165 main jet but when I looked at the needle there was no notches to move it to. So I put the bike back together and now im having an issue with it hesitation when I first crack twist the throttle. Can anyone help me with this?? Suggestions on what might be causing this or what I can do to fix it??

You need get the needle from OEM KX parts, JD jetting, or some other aftermarket manufacturers. Also an aftermarket fuel screw is one of the must items. Did you notice the hesitation before changing the main jet?

Which part of Ohio you live?

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return to your stock jetting and purchase a jet kit from JD, or dynojet etc...you will get a new adjustable needle, and a bevy of jets to choose from. Also get a fuel screw...it is a must for fine-tuning as you will be totally unable to make any adjustments with the stock screw...and you will need to make adjustments to confirm and dial in your pilot jet and to maintain a smooth idle during major elevation changes.

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Now which part of throttle opening you get the hestation at, 1/8, 1/4... Wide open throttle? Just hesitation? no stall?

I live in Sidney. I thought if you lived close to me I could take a look at your bike.

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the hesitation was around the first 1/8 to 1/4 turn when I hammer on it. The bike never stalled and runs good on the top. Im thinking I should of left well enough alone until I buy a JD kit. Thinking I will put the stock main back in until I purchase the kit. Have a race this weekend in Indiana and do not need any issues to work out before then.

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the hesitation was around the first 1/8 to 1/4 turn when I hammer on it. The bike never stalled and runs good on the top. Im thinking I should of left well enough alone until I buy a JD kit. Thinking I will put the stock main back in until I purchase the kit. Have a race this weekend in Indiana and do not need any issues to work out before then.

OK. Good luck on your racing! Which one are you racing, IXCR or Haspin? I might go race either one of them if I am not too tired from riding Perry Saturday.

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Leave the main alone. The bike is LEAN enough without mods. The removal of the Snorkal adds MORE AIR so dont down size the main again. Now your BOG is a LEAN BOG. You should have waited for the JD Kit & other parts so you could do it at once. Unfortunately it takes a bit more that swapping jets to get the FCR happy on your bike. You need to adjust the fuel screw, as well as getting an adjustable needle. Than if everything works well GREAT....If not, than you may have to adjust the AP Timing Screw. But 1st things 1st & get the Flex Screw & JD Kit....

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Ordered a jet kit today alone with a fuel screw and a new pipe. Should all come together in the end I hope

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Ordered a jet kit today alone with a fuel screw and a new pipe. Should all come together in the end I hope

All you had to do was buy the KX needle ncvr for 15.00 dollars and put it on the 4th groove from the top and you would have been good to go. The JD kit will do it for sure..:banana:

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Ordered a jet kit today alone with a fuel screw and a new pipe. Should all come together in the end I hope

Take a peak at thread "still having problems". The KLX airbox, filter and attatchment ring are a restriction and jetting hinderence if you are going to open up the exhaust.

Edited by ochster
Spelling errors...

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That is a very in-depth article. I have to say though, boy they did every last thing the hard way. Just check out my pic here. Subframe still on...shock untouched...all cables hooked up to the carb, etc. I wanted to show this picture back-to-back so people can get an idea of Easy/Hard.... :banana:

klxcarb.jpg

How did you reach the rear hex/allen screw on the top carb plate?

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I put a new silencer on, did the airbox mod, installed a dyno stage two kit, and a new fuel screw. The bike is running great but is backfiring alot! Any thoughts on fixing this problem??

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I put a new silencer on, did the airbox mod, installed a dyno stage two kit, and a new fuel screw. The bike is running great but is backfiring alot! Any thoughts on fixing this problem??

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Remove your AIS. That will cure your backfire. There are a few threads on how people have D.I.Y'd it...but i used the applied racing AIS block off kit. Cost about 30-40 bucks.

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I put a new silencer on, did the airbox mod, installed a dyno stage two kit, and a new fuel screw. The bike is running great but is backfiring alot! Any thoughts on fixing this problem??

As DIRK said, remove your AIS and I did mine without the kit. Just a few screws and some silicone. Most often, backfiring can be an indication of running too lean. Check your plug after a ride and it should be light brown in color. If it's dark or even black, try going down on your main jet. :banana:

Edited by Rome06379

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