Anybody ever heard of this Magic tool

7 replies to this topic
  • rvanliere

Posted June 09, 2002 - 08:41 AM


Factory R&D's P-38 Lighting is an advancement in carburetor performance that will work wonders for your Yamaha YZ400F and YZ426F and your KTM SX400 and SX520. The P-38, which enhances the accelerator-pump fueling system on all Keihin FCR carburetors bolts on in seconds and changes the timing and flow of gas being delivered to the combustion chamber. Factory R&D claims that the P-38 improves combustion for more power, making your bike accelerate faster, rev quicker and hit harder, enabling you to pull a taller gear out of corners. They say it also aids in starting your bike while hot or cold and eliminates Flat spots on bottom end.

Its make by factory R & D ( cant find them on the web ) would like any info if you have heard of this P-38 add on Mod

  • Fastest1

Posted June 09, 2002 - 09:09 PM


Save your money and do the BK mod. It does the exact same thing for pennies. Factory R&D has been around for years. They make jet kits, ignition advancers, and shift kits. :)

  • Mark_Cantrell

Posted June 09, 2002 - 09:12 PM



Lots of these bikes come with too much accelerator pump squirt. Enough to bog on acceleration. Recent bikes, including yours, can modify the AP squirt duration by adding a screw, the BK mod. Use the search feature. Before that, people did a variety of things, including the P38, adding wheel hubs from R/C cars, etc. Fast is right, if you have AP problems, try the AP mod. If you don't need it, neither would help.

Good luck,

  • dirtdad

Posted June 09, 2002 - 11:01 AM


Originally posted by Fastest1:
Save your money and do the BK mod. It does the exact same thing for pennies. Factory R&D has been around for years. They make jet kits, ignition advancers, and shift kits. :)

yes, they do the same thing but the BK mod does one better. It's adjustable, the P38 is NOT.
The BK mod is also a mere fraction of the cost.

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  • Bill

Posted June 09, 2002 - 01:47 PM


And if you have the early version carb, you can do the KL/Taffy mod.


  • Cobra314

Posted June 09, 2002 - 02:36 PM


I have a P-38 on my '99 YZ400. It freakin rips!! You can get them from They have a big picture with all the info in it. Mine works great!!!!!

  • eddiec103

Posted June 10, 2002 - 02:36 PM


RV i have a 99YZ400 and installed a p38 cause you cannot do the bk mod to my carb it made a big improvement bike rips now best mod ive done by far you can do the bk mod to your bike if you feel confident on working on your carb if not you can get the p 38 Factory R&D 949-206-0894 any ?s let me know!!

  • Shawn_Mc

Posted June 10, 2002 - 02:54 PM


Ya go with the BK mod, it wil cost you about a buck and a half. Just go look at the pics on motoman393 site. Garret took some great pictures and when you see it, it will make sense to you.

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