bump starting?

14 replies to this topic
  • crazyadam

Posted September 18, 2001 - 03:39 AM


I was just wondering if our babies are an interferance motor? Or wil the piston clear the open decomp valve? I have bump started her... but i only tap the decomp lever (very quickly, after finding TDC. I will not try this the hard way to find out, so I thought I should ask the ALL KNOWING!
Thanks again!!

  • *mike68*

Posted September 18, 2001 - 04:41 AM


I do it anytime I need to. If the piston couldn't clear the decomp valve, I would think you would hit it any time you went to decompress while kicking it around to find TDC>


Posted September 18, 2001 - 05:05 AM


I Bump Start mine every chance I get....Never have had a problem. Sure makes it easy if your short legged and stall on a down hill section.

  • The_Missile

Posted September 18, 2001 - 05:26 AM


What gear/technique do you use to bump start?
I tried gears 1-3 and just dragged my ass along the ground. Maybe I wasnt goiong fast enough. Whats the secret ???

The Missile

The Missile
'99 WR400F
Airbox Lid - gone
Throttle Stop - shorty!
Plastics/Tank/Seat - One Industries
Street Legal

  • crazyadam

Posted September 18, 2001 - 05:35 AM


let out the clutch while rolling, until back tire locks up, then tap the decomp lever, a little gas and your on your way!!

I had an audi V8, and like a subaru, if the cam stops ( broken timing belt, or chain) the pistons will slam into the open valves and then you throw away whats left. It didn't happen to my car, and I don't want to hurt my babie so I thought I would ask!!

  • slr

Posted September 18, 2001 - 01:55 PM


i use neutral, it rolls better. then all i do is click it in 2nd and pull in comp. lever, it starts every time.

  • funktree

Posted September 18, 2001 - 03:22 PM


Ive heard from several people and magazines that this is a bad idea so I havent ever pulled the compression release while bike was running. It takes a huge hill and fourth gear to bumb start it without it. you guys sound pretty sure that pulling the compression release is ok. It makes sense that if after a fall I can hold compression release and kick the hell out of the bike 15 times i could pull the compression release to bumb it. Im gonna bite the bullet and try it. I had a sore knee last weekend and didnt ride cause I couldnt get a good kick on th thing and would have loved to bumb start it

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  • ballistic

Posted September 18, 2001 - 05:42 PM


I used to own an old 1973 Yamaha 360 Enduro. After putting a new piston kit in, it had LOTS of compression. It kicked back so hard (ouch) when trying to kick it over that it broke the gear. With no more money to fix it, and being 12 years old and about 100 lbs. i started it anywhere by:

--fast push in nuetral
--hop on, clutch, catch 2nd gear
--jump up and bum drop the seat hard (for traction) as you let clutch out.

Worked like a charm.
Ahh, the good ol' days....

  • slashman

Posted September 18, 2001 - 06:59 PM


i start mine every chance i get with a down hill and the compression release. with the old XR's you used the compression realse giong down hill to slow down. i have not had any problem doing this.

Plus if i can not put the kick stand down i can not start my bike(legs tooooo short)

not yz timmed yet
some mods

  • Hick

Posted September 18, 2001 - 07:56 PM


When I stall it I automatically feather the decomp lever first thing, before I even grab the clutch, hoping to restart it. I have one of those GYT-R thumb-actuated realeases (expensive but I'd buy another), I think this makes it easier, but during a race I once restarted in first gear, in a corner filled with huge braking bumps, in a sand wash, with a guy right behind me. Unfortunately I fell on the last loop so he ended up passing me anyway.

I have a lot of experience stalling the YZF, so I’ve necessarily become proficient at restarting it on the go, and you can’t do that w/out the decomp. It is harmless, and is a good thing to know how to do IMO, even on the harder-to-stall WR.

My .02 Afganis.

  • *mike68*

Posted September 18, 2001 - 11:11 PM


I think bump starting and pulling the decomp while running are 2 different situations. I may be wrong.

  • The_Missile

Posted September 19, 2001 - 12:44 AM


Ahaaaaa.... yet another of lifes mysteries solved!! I ride mostly in the mountains and as a beginner have been stalling quite a bit and also have a lot of opportunity to bump start after a stall. Life just became that little bit easier !!


PS Too bad for those with short legs. I got long legs and I wouldn't want them any shorter than they are for riding the blue beast !

The Missile

The Missile
'99 WR400F
Airbox Lid - gone
Throttle Stop - shorty!
Plastics/Tank/Seat - One Industries
Street Legal


Posted September 19, 2001 - 03:06 AM


Mike....Heres the deal...If you stall and have a down hill grade of any kind, put the bike in 2nd gear, pull the decomp lever and roll down the hill (clutch out, It will roll) let out on the decomp lever slowly and the beast will fire off.

Been doing this for two years on my 99 and have had Zero mechanical problems because of it.

(I can hear the masses now.....Oh you'll destroy the upper end and go to hell for doing that!) :)

Bonzai :D

  • Roostie_1

Posted September 19, 2001 - 12:29 PM


I moved the decompression lever to the throttle side and it works like a charm. You can operate the clutch and decompression lever seperately and at the same time, plus when you stall it in a race it keeps your hand off of the throttle (old two smoke habits are hard to break sometimes).

Anyways, it also works great for bump starting :)

  • Itsamre

Posted September 27, 2001 - 12:01 PM


Pull in the comp. lever and the clutch lever, get rolling (downhill) in any gear, let the clutch out first to get the motor rolling, then let out the comp. lever. Starts every time!

Mark...00 426 w/plates,and $4000.00 of other attachments!


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