Can anyone recommend a good motorcycle mechanic in the Ensenada/Maneadero/San Vicente area?DanO - 10-11-2010 at 10:38 PM
Bump please, I need some help tuning my WR250R's carb. Anyone? Or should I just take it back stateside?DENNIS - 10-12-2010 at 06:14 AM
DanO....Where are you? La Bocana?TMW - 10-12-2010 at 09:02 AM
Quote:
Originally posted by DanO
Bump please, I need some help tuning my WR250R's carb. Anyone? Or should I just take it back stateside?
What about tuning do you want to know? What is it doing?
While there is some overlap in the adjustments tuning is primarily related to 1/4 throttle settings and checking the spark plug. What year is it? I am
familar with the YZ250. Basically there are 6 componets to a 2 stroke MC carb. 4 regulate the flow of fuel and are the jet needle, needle jet, main
jet and pilot jet. 2 regulate the flow of air and are the throttle valve and pilot air screw.
The pilot screw and jet work from idle to about 1/4 throttle. Throttle valve cutaway works from about 1/8 throttle to past 1/4 throttle. Needle jet
and jet needle work from 1/4 to 3/4 throttle and the main works from 1/2 throttle to full throttle. Normally you start from the stock settings and
then work from there depending on where the problem is.TMW - 10-12-2010 at 09:11 AM
I looked up a WR250R and I was wrong thinking it was a 2 stroke. But the function is still the same just not as many adjustments usually.rts551 - 10-12-2010 at 09:14 AM
Yes there is but I don't have the info here (I am in the states right now). Ask around town.bajabass - 10-12-2010 at 09:22 AM
The newer Yammie 4 stroke use a flat slide, diaphram carb. Is the jetting stock, and what altitude are you riding at? What rpm range is your problem
at, and is it rich or lean? Have you read the plug? What color are the carbon deposits? Most stock bikes these days are jetted spot on for sea level.
Have you done engine performance upgrades or changed the pipe/silencer?
Many variables, therefore many questions.DanO - 10-12-2010 at 11:40 AM
The only carb mod was the replacement of the stock throttle stop screw with the YZ version. We're at sea level, and the bike was last jetted/tuned at
the same level. I subsequently removed the stock exhaust insert and replaced it with a Graves hi-flo insert.
The issues started after that. The bike sat around for awhile and then fuel started pouring out of the carb overflow hose whenever the fuel valve was
opened, indicating a stuck float (and making me a rolling fire hazard). I broke the carb down and cleaned out a little varnish, reassembled it (did
not change any settings), and that (along with some Sea Foam gas treatment) did the trick on the float/overflow problem. The problem is that the bike
now will only run with the choke fully out, which seems to indicate just a mixture issue, but I'm worried that I bent something in my DIY carb
cleaning effort that requires professional assistance.
Thoughts? Bike is 2006.
Dennis, see your U2u.TMW - 10-12-2010 at 11:58 AM
I suggest you take it appart again and inspect it, I think the main jet or associated hardware is plugged part way. If you have a bottom plug you can
remove it and unscrew the main jet to check it. But you may have to just take it all apart again for an inspection. The only thing I think you could
bend is the float or associated part. Give it another try what to you have to lose.DirkEXC - 10-12-2010 at 12:13 PM
It sounds like you want to get it to a shop and have it done and be done with it . A couple of things you might try before you take it in. On some
bikes you can loosen the clamps on the carb and rotate it so you can get the bowl off without taking the carb off. With the bowl off check the main
and look for junk on the bowl. Also I know it sounds dumb but since you mentioned junk in the gas make sure the screen on the pet c-ck inside the tank
is clean. A cloged petc-ck screen can make a bike do funny things.Diver - 10-12-2010 at 12:25 PM
If the bike runs with the choke on but not off, you have a flow problem.
Re-clean the carb paying attention to the pilot jet (it has a very small hole but must be totally clean - try a single wire off a wire brush and spray
carb cleaner).
Consider an inline fuel filter just below the tank valve in case their is crud in your tank.
Also, if you increased the size of the exhaust, you increased air flow through the carb. This normally requires a needle clip adjustment or larger
main jet but this has nothing to do with having to use the choke to keep the bike running.Diver - 10-12-2010 at 12:30 PM
Also, careful with fuel containing ethanol; it goes bad faster that premium lead-free.
Use a stabilizer or Seafoam and/or drain your carb when you put the bike away for more than a few days.DENNIS - 10-12-2010 at 01:05 PM
DanO.....I checked with the local race boys...they all drive cars...and their info was vague at best. No last names or streets...typical nonsense.
They all said Ensenada....nothing closer to here. Sorry.DanO - 10-12-2010 at 01:32 PM
All responses appreciated. Looks like I may have to waste another afternoon on the bastard. Or, I could take the view of one of my Mexican
neighbors, who asked, "if it runs with the choke out, what's the problem? Just run it with the choke out."bajabass - 10-12-2010 at 02:07 PM
You have a restriction through the idle/low speed circuit. Clean it again. The only reason it runs on choke, is the mixture is too lean. Not enough
fuel. Drain the tank, clean the petc-ck filter, blow out all the jets, and all fuel passages. Use fresh premium fuel, throw in a new plug, make sure
the airfilter is clean. Oh, check for a rag in the airbox! I left one in once, boy did I feel STOOOPID! As far as the pipe goes, you may need to raise
the needle one notch, by lowering the clip. Get it to run first, then worry about tuning for a minor exhaust mod.TMW - 10-12-2010 at 03:08 PM
If you need a pictorial of the carb go to http://www.bikebandit.com and look it up. It will show you all the internal parts etc.
[Edited on 10-12-2010 by TW]DanO - 10-12-2010 at 03:42 PM
Quote:
Originally posted by TW
If you need a pictorial of the carb go to http://www.bikebandit.com and look it up. It will show you all the internal parts etc.
[Edited on 10-12-2010 by TW]
That is awesome. Like being behind the desk at the parts counter. Thanks.DENNIS - 10-13-2010 at 09:10 AM
Anything good happening, DanO?DanO - 10-13-2010 at 10:46 AM
We'll know in a couple of weeks, assuming I muster up the energy to git er done.BajaWarrior - 10-13-2010 at 05:04 PM
Quote:
Originally posted by DanO
We'll know in a couple of weeks, assuming I muster up the energy to git er done.
I say like others here it is a plugged pilot jet. Like Diver said go at it with a single bristle from a steel wire brush or a needle/pin and then hold
it up into the light to see a small opening, well, check it first for a clog then clean.
I have a bunch of ATV's and i'm always working on one or two at a time just from them sitting around.
BTW DanO, we'll be down on the 23rd/24th this month.
