de-compression lever mtg up or down ?

15 replies to this topic
  • 99400f

Posted November 28, 2001 - 04:40 AM


do you guys have any feedback on this ?

  • thumpy

Posted November 28, 2001 - 05:41 AM


I prefer the down position. It's tucked away during a crash and not as likely to get snapped off (although it can be snapped off). It's also easier for me to reach down for the lever when tired then it is to do the awkward up reach when it's in the up position and more prone to damage in this position as well. So there you have it, conclusive evidence that the lever can get damaged in either the up or down position and the only real way to prevent damage is to keep the rubber side down.....

  • 99400f

Posted November 28, 2001 - 06:33 AM


can valve damage happen if the lever is compressed while the engines running ?

  • FOX426

Posted November 28, 2001 - 06:49 AM


Yes, valve damage can happen. The down position is the preferred position, most pros run them there.

  • 99400f

Posted November 28, 2001 - 08:52 AM


does anyone make a small lever a remote hotstart..or something like that..because it really does'nt take much pull on that lever..i figure i can get by with something much smaller..and mount it in a place that for sure nothing can go wrong.

  • Glen_T

Posted November 28, 2001 - 09:41 AM



  • Taraker

Posted November 28, 2001 - 12:42 PM


Down, less chance of me grabbing the wrong lever during a race

  • neWRiver

Posted November 28, 2001 - 01:11 PM


I've been told a couple times that the decomp lever can be used as an "engine brake". I've not had the nerve to try it. Anybody use it this way?

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  • F-Pilot

Posted November 28, 2001 - 02:03 PM


Ran mine down on 1 ride, lowsided and broke it off. No fun trying to start these beasts without it.
I do run my levers at a down angle which made it real low on that ride. With it on top I can run it almost horizontal and grab it easy if I stall.

  • Hokie

Posted November 28, 2001 - 02:28 PM


Originally posted by 99400f:
does anyone make a small lever a remote hotstart..or something like that..because it really does'nt take much pull on that lever..i figure i can get by with something much smaller..and mount it in a place that for sure nothing can go wrong.

Works connection has a good one, not remote, but smaller. I had one on my 99 YZ400 for two years and never broke it.

Look at:


  • rmarion

Posted November 28, 2001 - 04:19 PM


Down is Best.

Goin down is better. :)

It can still break off, broke of on a 50' double - double, prezled my Rentals, broke the compress lever and totaled the Big Belly Body.

The bikes runnin, the body is barely walking.

Gone Motoin.

  • Sanch

Posted December 01, 2001 - 12:13 PM


Okay, I know I'm branching off of the subject of whether to have the lever up or down, but 99400f opened the gate.

I read that if you flood the bike, you can hold in the decompressor lever and kick it over 10-20 times to "pump out" the extra fuel. This is supposed to help you get the bike started sooner.

I'm not saying that FOX426 is wrong, I just want to check to see if anyone knows for sure...

  • YZ400Court

Posted December 01, 2001 - 05:27 PM


Hold open the comp release, twist the throttle wide open and hold it there, and kick through 20 times. This will clear out any fuel flooding the engine. Remember when you twist the throttle you add more fuel to the mess, so only do it one time and hold it open till done.

You can pull the decompressor from the head and grind it down some to minimize risk if the lever is hit by accident while the engine is running.

  • motousa

Posted December 01, 2001 - 07:51 PM


All right everyone, just wanted to add my two bits...I run mine up...different from most but I have a good reason. When I corner my legs hit the bars, I am only 5'11", but it is in my style, lay it over and stick your leg out there :) . I will finish a moto and have bruises on the tops of my legs from the brake master-cylinder bolts. If any of ya'll have this happen, then the decompression lever will definitly interfere, even if your clutch is high!! Keep in mind that your leg will generally only hit on really rutted corners, so if you don't ride on these types of tracks, it may be worth your time to run it "out of the way" and low. I have had NO problems with it on top yet.

  • Slice543

Posted December 01, 2001 - 09:45 PM


I run my down. When I ride trails there seems to be trees and branches that jump out from nowhere and I was always worried about them hitting the decomp lever while the engine is running and causing valve damage. Now, I have endoed my bike in the whoops at a state race and broke off the lever, but there was just enough left to get a finger on to pull it in. I would have to say 95% of the guys I ride with, ride with it down. Just don't ride with it in the forward position like it come from the factory. Also, if you change bars are change the position of the lever, be sure the perch is not mounted too far out, because every time you make a left hand turn, your bike will magically stall.

  • funktree

Posted December 02, 2001 - 07:43 AM


I run mine down because it makes it easier to start in gear i can hold in the clutch and use the lever with one hand when its in down position

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