Starting

 Why are some bikes a royal PITA to start (my YZ250FV) and others absurdly
quick and easy (any CRF)? Is there anything that can be done to make the YZ
start like a CRF? Painting it red is not an option.

 On 7/31/2011 5:12 PM, Schmoe wrote:

Man, we found that keeping the valves right in spec, (low side for us,
we race), the bike (RM-Z250) starts pretty much first kick every time.
When hot, or after a quick dismount, a thumb on the hotstart and it
might take three kicks...

Rowdy Mouse Racing . com

 

Red will make it worse.

Check your exhaust valves.  They're too tight.  If you want it even better
than what that will bring you, get a JD Jetting kit and follow his
instructions to the letter.

 Hi!

On Sun, 31 Jul 2011 17:12:15 -0400, Schmoe wrote:

That wouldn't help (KTM tried it with a few of their models and failed). An
easy starting bike distinguishes from the royal PITA in various things:

Maintenance level (valve freeplay, airfilter status, spark plugs, ...) as
well as carburator setup (idle mixture, start jet size - if there is any,
routing of vent tubes, air leaks, ...), battery/alternator/ignition
coil performance and last not least a few not so obvious things, i. e. a
tight petcock: The bastard in my KTM's fuel tank, from Mikuni btw, doesn't
completely shut off fuel in its "OFF" position which means that a) emptying
the carb bowl doesn't make any sense as long as there's fuel in the tank
and b) you always have old fuel in the bowl because it continuously
dribbles in there.

Since there are also internal, "built in"-differences such as compression
ratio, size and geometry of the cylinder head and piston, exhaust,
kick-starter gear ratio, you might never be able to make any bike start as
easy as a well known nobrainer. But I had good success with my KTM (which
translates to K_ick T_En M_inutes for various of the above reasons) and
make it start fairly quick, usually after the 3rd kick.

But I would never dare to make the same statement for my orange methusaleah
as Yamaha did in the YZ426F manual: "If - after following the
aformentioned starting procedure - the bike doesn't start on the third
kick, it's defective and needs to be repaired.". Indeed, those guys where
right. Usually, if the YZ doesn't start 3rd kick, it doesn't want to start
_at all_. Any in any of those cases (about 3 so far, in a period of 10
years), it needed a new spark plug.

Cheers,
Volker

--
@:  I N F O at B A R T H E L D dot N E T
3W: www.bartheld.net

 
My first check would be jetting... assuming everything was in spec.