P-38 Lightning question

6 replies to this topic
  • Chaindrive

Posted October 08, 2002 - 04:35 PM


Does this device allow a '99WR to be accelerator pump tuned like the Motoman 393 (BK) mod does for newer bikes, or am I really confused? Does it work? Will one for a 250F work on a WR400? :)

  • MN_Kevin

Posted October 08, 2002 - 04:51 PM


for the 99's there a 3 methods for achieving a "BK" mod.

1 - the "KL" mod. This is my approach. It consists of drilling and tapping a hole on the cover that fits under your accelerator pump diaphragm. You then insert a set screw and locking nut. This will prevent the AP from opening too much thereby limiting the pump stroke. I used teflon tape on the threads of the set screw. I have had absolutely ZERO leakage.

2 - Taffy Mod. This uses a clamp that fits on the AP rod, which is external on the carb. It also limits the stroke of the AP by limiting movement of the rod.

3 - buy a P38.

  • freestyle111

Posted October 08, 2002 - 05:31 PM


i have p-38 on my wr400.it definitly works.i cant say if it works any better than taffy,kl,or bk mods.they all basically do the same thing.i know that p-38 is the most exspensive of the 3 ways to get rid of that off idle bog.it is probably the easiest of the 3 when it comes to installation and getting tuned in.if your on a budget i would go with taffy or kl mod,but if $79 is no big deal then p-38 is way to go[it also looks pretty cool]

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Posted October 09, 2002 - 03:21 AM


I did the Taffy MOD on my WR and the P-38 on my YZ. Both work equally as well but the P-38 was much easier and less time consuming. It cost me $1.05 to do the Taffy Mod and $65.00 to do the P-38.

Bonzai :)

  • WR_Jason

Posted October 14, 2002 - 09:31 AM


What kind of clamp are you guys useing for the Taffy mod?

There is another method called the Jason mod.
You let you AC pump fill up with trail grit that limits the return of the diaphram and thus the stroke. Trying to get just the right amount of trail grime in there and packing it down is a bit of an art but lots of fun trying to find it and get it in there :D

Oh yeah and the P-38 Lightning was a Persuite/Ground attack twin engine aircraft built by Lockheed I belive that saw action late in WWII. It was dubbed "The twin tailed Devil" By the Germans on the recieving end of it. The plane was a good ground attack aircraft but laqued power to menuver in air to air combat so it was upgraded with twin superchargers and became an admirable air combat figher with its 6 (I think) nose mounted multiple caliber guns and large ammo capcity. It was one of the first and most successfull platforms for non guided rockets that were retrofitted from ground based rocket launchers to the wings of the aircraft. Most pilots were very pleased with the P-38 Lightning except for one major short comming, with the engines mounted on two booms and the cockpit in a pod in the center, the aircrafts heating system was pittiyfull, more pilots suffered frost bite than combat loss or injury.
LOL :) .

  • Taffy

Posted October 14, 2002 - 01:15 PM


for the Taff mod over here in europe we would use the metal centre from what we call a block connector. they are used to fit car radios in and wire it up etc. the idea is that you would feed the two wires in; one from each and and there is a minute pair of screws on the side, one for each wire.

i'm told you don't use them in the states muchif at all. so a lot of blokes have been fitting small radio car model "wheelcollars" the correct size of which someone else may mention to you 1/8th" i/d sounds good.

pull the rod off and slip the collar on, adjust to correct amount of lift then drop the gaitor back over the collar to hide it.

tiz that easy.

the P-38. well it was a famous body filler over here. yup! isopons P-38. along with a bit of chicken wire it's responsible for duping more people than uri geller.


  • MN_Kevin

Posted October 15, 2002 - 01:21 AM


The P-38 Lightning was an outstanding aircraft under the right conditions. It had 5 nose mounted 50 calibers.

The aircraft did not have a heated cockpit as mentioned already. The P-38 was removed from the ETO late in WWII because of this.

On the contrary, in the Pacific campaign, the army air corps could not get enough P-38's. She could OUTURN a Japanese Zero (made by Mitsubishi).
The highest ranked US pilot during WWII was Dick Bong. He flew P-38s in the Pacific. He shot down 40 confirmed kills.

The P-38 shot down Admiral Isoroku Yamamoto, on a carefully planned ambush, who devised the plan for the Pearl Harbor attack. (As a side note, Isoroku Yamamoto was educated here in the U.S. >> some college in California!!)

It WAS operational in 1942.

There is a book about her: P-38 Lightning: The Fork Tailed Devil.


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