What's the best way to start a YZF426?

hi, i am new to the 4-stroke seen. bought a 2001 YZF426 and when i get it started, it's awesome. i've been having trouble figureing out how to start it. i got the copm release down but not sure the best way to kick on it. it seems when i kick it hard, it won't start. when i kick it softly, it tends to start easier. any advice on starting these things?

1. 03 Cam mod

3. Valves in spec ?

2. Clean Carb

when I first got my 1999 yz400f I struggled starting it too. The main thing in learn the starting procedures. they are posted in many threads in this forum.do a search, you will learn some really cool stuff. Try to get a manual on the bike , that will help you a ton.

The main thing on mine is to not touch the throttle. I start mine with my hand on the brake m/cylinder. cold, full choke, no throttle, get the bike on top dead(kick starter hits hard place), go about 1 click past that point, let the kick starter back up to the top, then give it a full kick, all the way down. I was kicking mine like a 2 stroke and it would not start. A full kick seems to work good for me. Then let the bike warm up for a minute or so before you try to give it any throttle. When the bike is warmed up, same proceess, without the choke. Mine usually starts first or second kick even when I have dropped it.I have yet to have to use the hot start. Also you will learn these bike do not like to go slow or be left idling for any amount of time. They get hot pretty quick. Also, don't ever let anyone twist the throttle with the bike not started as these bikes have a pumper carb and they will flood like no other. Just a few of what I have run in to in the first month of owning a yzf.

anyway good luck with the bike

jay

just noticed i left out pull decomp lever, but you already know that, to get the kick starter past tdc.

sorry, trying to work and type

main things to remember:

1) do not hold down the comp release while kicking. Only open it to bring kickstarter to TDC. Then bring the starter up and let go of comp release.

2) kick the starter through its FULL STROKE. 4 strokes are not like 2 strokes. 4 strokes only fire ever other stroke; 2 strokes do it every stroke. So, you want to kick it smoothly and through its entire stroke, whereas w/ 2 strokes you mainly just need to kick it hard.

thanks for all the tips guys. i've been giving it 2 twists of the throttle so maybe it's getting flooded. i noticed the exhaust header gets red hot when riding slow. is this normal?

anyone know where to get the auto decompression set up?

thanks

The auto decompression setup is simply a replacement exhaust cam, either an OEM YZ450 cam (which takes some special installation, but nothing complicated), or an aftermarket unit. TT OEM Parts has them. You'll need $10 to sign up, but then you'll only pay about $100 for the cam.

i've been giving it 2 twists of the throttle so maybe it's getting flooded. i noticed the exhaust header gets red hot when riding slow. is this normal?

It has probably been flooding with that much fuel.

It is normal for the header to get that hot and turn red.

bike is simple to start once you no how.will generally start within a few kicks, but as mentioned before no throttle at all,find TDC and then crack the decomp lever a fraction with pressure on the kicker,if you go down more than half inch it wont start, release decomp let kicker come back up and kick.dont even need to kick that hard,seems to all be in getting the valves to be only just open.when i first got mine couldnt start it for 2 weeks or walk from trying,all my rides ended up with me pushing the thing back to the trailer,as when i stalled while riding just couldnt get it going. was about to get rid of it when i met 2 other 426 riders who saw me pushing,and showed me how its done.ive got to tell you the 426 rocks,got mates on all sorts 450s and for shear torque/grunt the bikes a sweet weapon. is heavy to turn though and i still have fun watching mates trying to start her, lol

These bikes heat up very quickly and need to stay moving quick enough to keep air flowing through the radiators. The glowing header is a common thing to experience with these bikes. If you haven't switched your coolant from regular ethylene-glycol to something else, I recommend Engine-Ice. It comes ready to use with no mixing needed and works great.

One simple thing no one has seemed to mention to help starting your 426 is a fresh spark plug. My '02 will foul the plug if I mistakenly give it gas when trying to start it. Once it starts to foul, my bike becomes a bear to start.

Hope this helps and congrats on choosing a great machine to ride:thumbsup:

step 1: look in manual

Cold start:

pull choke

hold decomp lever

kick through about 10 times

find TDC

crack decomp lever a pass the kickstarter abotu 1 1/4 inch past TDC

then all the way to the top

then kick all the through

When hot/stalled:

pull hotstart

dont bother going through entire decomp process

find TDC

crack decomp lever a pass the kickstarter abotu 1 1/4 inch past TDC

then all the way to the top

then kick all the through

it works for me. my bike starts first kick, everytime. it take a bit of practice. never touch the throttle

Funny how many people have had problems with starting the 426's... I've never owned anything but 4-strokes, and mostly XR editions but when I upgraded (HUGE UPGRADE) from my '87 XR 250 to my brand spankin new '01 YZ426 I had no trouble at all, actually not even if I went down... Now, if I let someone else load/unload/ride my bike then and only then would I have trouble and it was due to them flooding it so bad I would need to change the plug....

step 1: look in manual

Cold start:

pull choke

hold decomp lever

kick through about 10 times

find TDC

crack decomp lever a pass the kickstarter abotu 1 1/4 inch past TDC

then all the way to the top

then kick all the through

When hot/stalled:

pull hotstart

dont bother going through entire decomp process

find TDC

crack decomp lever a pass the kickstarter abotu 1 1/4 inch past TDC

then all the way to the top

then kick all the through

it works for me. my bike starts first kick, everytime. it take a bit of practice. never touch the throttle

Whoa! Serious? You kick it through ten times first? These bikes are funny and they all seem to have their own small differences to starting...if I ever did that with mine it would never start!

I installed the auto-decomp cam so with mine I just kick it through good and hard once and it fires right up...however, I give it one quick twist of the throttle first (whether hot or cold) then take my hand away from the throttle when I kick it. When I first got the bike I would never twist the throttle prior to kicking and it would fire in one to three kicks but once I tried giving the one twist first it fires up first time. Funny thing is that I know there are 426's out there that will not start that way.

I'll start with the 02' 250F I recently traded for my 00' 426.

The 250 was a pig, it never wanted to start. I would have to replace the plug after 2 rides. The carb was tuned to specs and the valves were shimmed or replaced on a regular interval...like any race bike should be.

That bike just hated being started....period. It ran great..but if it quit...you could cancel Christmas because your race was over.

Then I read a thread on Thumper FAQ, about a starting drill. The drill included holding the throttle open for 10 to 15 seconds before kicking it (I'm not kidding) I thought it sounded rediculous, but I was at my wits end so I tried it....it actually worked better?

Then I just sucked it up and installed the 03' Cam ....life got a lot better! :cheers:

Now I have a 00' 426. Here's my drill:

-Pull choke

-Hold throttle WFO for 10 seconds....then release

-Pull De-comp. cycle 3 times

-Let the kicker come fully up to TDC

-Rest my foot on the kicker, just enough to apply weight

-Pull the De-comp, let my foot weight the kicker to the first "click" or stopping point.

- Release the De-comp. lever and give it one good kick all the way through, and it fires.

Twice is the most I've ever had to kick this thing.

The Hot Drill is the same, minus holding the throttle open, and add the hot start button. :p

I was reading this post through and it is amazing how many people stress to not give it any gas whatsoever. I have owned thumpers since they were heavy undesireables and have found the following system to work well and usually start on the second kick:

1) One quick blip of the throttle and then put your hand on front brake reservoir.

2) Kick through to TDC (the kickstart will pretty much refuse to go further)

3) Pull in Decomp and kick down 1/2 inch then let go of Decomp

4) Bring Kickstart back up and give a nice firm kick all the way through the stroke.

In the last step it is very important to kick all the way through and do not kick it too fast, it is my understanding that the Decompression does not work correctly if it is kicked over 750 RPM. Hence, you drop your bike in the last turn and kick like a lunatic only to find that it starts when you are dead tired and dead last. Just my 2 cents.

Oh, and if you think these current bikes are hard to start I used to have an early 90's KTM 600 with the left side kick and I have a 30" inseam. People used to ask if they could ride it and i'd say "Sure, if you can start it" No need to lock it up.:cheers:

WOW! thanks for all the hot tips guys. after all your feedback on this issue, i've learned that the yz426 likes no blips of the throttle and hand on the master cylinder. this made life so much easier last weekend at ocotillo wells. the thing started within 3 kicks everytime. thanks again.

got a new issue now. the bike seems to get hot and spill fluid out the over flow when sitting or riding slow. i think i will try replacing the radiator fluids with the ice stuff. anyone else have issues with overheating?

anyway, the bike is so much fun now that it is easy to start. it blows my stock 450x to pieces. my next move will be to make the 450x move. lol

yes.... mine got hot too the first time i rode it slow and left it idling. I put engine ice, a new cap, and really watch my ride speed and idle time and don't seem to have that prob anymore. I read in a post in here the speed number is like 8mph,minimun, to keep enough air flow to keep those cool. I don't let mine idle at all once warmed up. If we stop i shut it off. 8 mph is not that fast, but it can be in tight trails. I put a trail tech computer to keep up with ride time/mileage and it shows mph also.

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