yam wr 400 f

5 replies to this topic
  • dazza fairless

Posted September 21, 2008 - 03:59 AM


starting any one know of an electric kit for my bike. or any way of making it kick over easyer without taking my foot off doing it....please

  • genebrp

Posted September 21, 2008 - 04:50 AM


Are you familar with "Just past top dead... stroke, don't poke?"

The key is that you keep in good tune with jetting (which includes air in to exhaust out), valve adjustment, decarbon head with a good plug and of course other minor to major items that keep your motor at the top of the game.

Once you have that in fair control, cycle through the stroke until top dead center on compression is found. Simply the "height of resistance", use the compression release to glide just past. Then full stroke kick.

KEY: You must be in a position that you can apply all your weight to the stroke. Stand on a rock, put it on a kick stand... be planted... Kicking it like the old 2 strokes just ain't gonna happen.

There are tons of articles on kicking 4 strokes... Electric starts are nice, but not necessary. More convience than need.

  • byggd

Posted September 21, 2008 - 05:43 AM


Once you get the starting “ritual” perfected the 400/426 should start within three kicks cold and one once warmed up. That said it did this mod to my 426 because I tend to flame out on hill climbs more than I care to admit. :excuseme:

One of the BEST mods I have done to date!

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  • 1rkcooper

Posted September 21, 2008 - 08:00 AM


The auto decompression upgrade will make you think that you traded the WR400 in for a 2 stroke. If your jetting and the valve clearance are correct the bike should start easy without auto decompression but is a dream to start with the mod done. I think the TT store sells the yz450 cam for around $120-$130.

  • tcmII

Posted September 21, 2008 - 07:16 PM


I just did this cam mod this weekend. Now my 13 year old can start my 400. He 5'10" 130 pounds.

It took two tries for me to get this right. Make sure you align the cam as described in step one and adjust the valves properly (I made the left valve a little tight, but within spec, because that's the one the cam button opens for decompression). Make sure you check the intake since your in there anyway.

  • creeky

Posted September 22, 2008 - 03:19 AM


Keep practicing the proper starting drill using the manual decompressor. Once you master it, you can start the engine with very little effort.


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