125-200cc 09 Wr 125 Bog/Performance Solved?

Typpt
Have you tried your settings in varying temperatures?
Cooler weather may make a difference - same with Dyno tuning

variances in condiitons may be a problem once dialled in - will still have to make adjustments to suit

Id pay to see a PWK to Mikuni comparison though ...
Also what are the thoughts on what PA Ktm said about adjusting Power valves - adjust top bolt as middle linkage doesnt do anything ? Walt ? I thought it did make a difference to mine..

Yes, varying temp will require minor tweaking. On my yz125 between winter and summer about 1 clip leaner on the needle and one leaner on main. Could also stand a size larger pilot in the winter(stock size). The dyno has and always gets all the basic temp and barometric pressure, altitude input before use to have it correct its reading/results. I would not bother doing this with any other dirt bike I have had to date as I have been able to adjust them ok. This bike(wr125) had/has a serious jetting problem and mine may even have a fuel flow/supply problem; will test the RM needle first for that issue. I would be happy to test someones pwk on my bike if it is sent to me. Power valve testing will follow for some no BS what does what and I am keeping my opinion to myself for now on that.

Today i got the Rm needle and the 144cc Hgs exhaust, was little ritch in 3clip, moved to 2clip position.
Runs great, a totally new bike, pulls real hard from bottom to topp no bog.

On my power valve comment/picture…all the adjustment is still done with the lower bolt/slot to put the preload on the spring tang. Just don't be concerned with where it ends up in the slot. The preload is what you're after.

gsxr what part of WV? I went to high school in St. Marys. This is good tech stuff, by the way. Starting a new thread is good, but so is tagging on the back of one. Kind of gives a history of how we got there…

My son's collarbone is on the mend nicely, we're shooting for the Powerline Park GNCC in Ohio.

dartyppt, You must be a member of the AMA, National Hot Rod Assoc. and Landscapers International. And yes, currently I do have the stock/silver combo in. My son seems to like it best.

My son has a friend that does motocross with a current year YZ125, which has the 38mm Mikuni.
His dad has a full machine shop and part of that business is building top end kart engines.
Needless to say; dad finally said bring the WR to the shop with the Mikuni.
Things moved fast…this guy doesn't screw around and at this point…whatever!

The only thing I was, and still am missing is the Suzuki CHY needle. Hopefully it comes in today.

Ended up with carb having a reverse taper bore on the reed side, the head cut down and the following…

480 main
45 Pilot, air screw 1 1/4 turns out
Stock BFY needle, middle clip.
# 5 slide
Stock BR9EG plug gapped at .020
Slight tension on power valve spring tang.
FMF Pipe/TC2 silencer
Maxima Super M 40:1

Runs the best that it ever has. Good pull off bottom/good torque, no bog, rips right through to the top.

I believe it's still a little lean… kart guy says go up on the main, but I want to try the new Suzuki needle first.

I'm going to clean out the pipe, repack the silencer, pick up a bigger main, get some new plugs and hope the new needle comes in.

crille, good looking piece of machinery….who's/what skid plate do you have?

Have a great weekend.

Charleston, downtown. I have a auto repair shop. Charleston High-End Motorworks. I did give props to dartyppyt as he does deserve a lot of credit for steering us in the RM direction.

paktm, I need someone to help me confirm a flow restriction/limitation with the DEY needle, or your BFY(but it is a leaner needle). I found going way too large on the main made no change. I drilled one out with a 3/32 bit which is very large compaired to your 480 and still not blubbering; very lean up top. I have removed the main nozzle and made sure it was clean and did serveral other checks and I cannot get it rich or even close up top with the stock needle choices. Still waiting for the RM needle!

Back from lunch with new CHY needle in hand…very strong taper at the tip. Sorry about the quality, mephone at desk...



dartyppyt, I do have smaller mains to try, if you think this will make it that rich…Thanks

gsxr, there is some confusion here about the stamp on the needles…
It's possible that the DEY and BFY are actually the same needle.

Check out the 'CR/WR125 Index Thread', (4th thread down in 2 stroke forum.)

Under; Carb topics
Under; Mikuni TMX Jetting Info (By Motosportz and other members)
Start reading at the beginning, there are some pictures, than...
Around reply #10 - good discussion as to what's on the needle and by #13 I think there is confirmation as to what was in the bike, stock vs. update kit.



If you have the original and update needle - you may have one of these mysterious DEY/BFY needles.

Hope this helps...

Interesting, I've had a similar experience with my WR250. I've changed mains from 390 to 460 and it's still not right from 3/4 to wide open. I'm wondering if my needle isn't going high enough to fully open the main circuit.

Well no needle after 4 days on order. So lets go old school and brake out the sandpaper and drill. My bike came with the BFY needle in it and ran like shit. Ran a little less shitty with the DEY that I think is the kit needle? Does not matter they are both crap. I took the BFY and chucked it in a drill and spun it using sandpaper to retaper the point much finer and worked it up the needle about half way. After some trying I finally see a little color and am way rich in the middle with the clip 2nd to rich. No mains larger than 470, used my 3/32 drilled jet to see if I could get the bike to blubber up top. And yes finally it was so rich it shut off when it came on the main; to rich to fire! RM needle should be perfect and will post charts in my thread and this one next week if I get the dam needle

I have thought about checking the power valve but haven't done it yet. I can feel it come open when I'm trail riding and it doesn't feel like it's closing right away when the rpm's go down.

It's and '09. I'm at 6000ft and have settled on a 30 pilot and the GAY needle in the 3rd clip position and it runs great everywhere but on the main.

Even though I am very happy with the PWK, I also have ordered the RM needle. I have the carb and everything else so why not try it and compare. I am only going to use it for the 144 as the 167 is the bees knees with the PWK everywhere. Awsome motor. It does require a couple of steps richer on the main so I am wondering if the Mikuni will feed it with the RM needle and may need the 61 or lower?

Keep up all the good work guys as we are all paying attention,

Walt

Changed out the needles, haven't got a chance to test ride yet...

I think my tester is just getting out of bed.

Below is a quick look at the BFY needle that does exsist.

Talk about a step taper...

Thanks Darty,

We will see what happens.

Couple of really short videos, more for sound than looks. (taken with iphone)

We are really close, very excited about the performance.

2009 WR125, with update kit and the following for now...

470 main
45 pilot
air screw out 1 1/2 turns
CHY needle, middle clip
# 5 slide
Stock PV spring with small silver inside
BR9EG plug, gap .020
FMF combo pipe/TC2 silencer
Maxima Super M 40:1

Yes, it was dusty but raining right now...

Look and listen, let me know what you hear...

Thanks,


http://www.youtube.com/watch?v=Lq5Ya1s-m-w

http://www.youtube.com/watch?v=G2ZLkMMP9Ts

http://www.youtube.com/watch?v=4_4NOD0dmmc

Credit when its due

Darty, can we see a pic of yer arss? It must be very finely tuned as so far my dyno testing says you have a sensitive, accurate one indeed.

Darty, I would also like to do some ignition timing changes and see whats what on the roller. I need to get a flywheel puller; do you know if other will work? I think I have seen that a ktm may work? I also want to try the base gasket but think I already have a very thin one on the bike. I have had the head milled about .017-.020 before the dyno work but could not really determine if it helped. Think it did but I was running too small a pilot and the orange pv spring so the bottom was wacked. It helped my yz125 a little. Basically it brought my squish band on the wr from about .055 down to .040 or so. I have read that this is still a little on the thick side? I don't have any detonation that I can hear, no pinging. On the rollers at high load/very low rpm I may hear a little detonation but not of any worry as its so low below 3k rpm hardly ever use it there.

My 144 pings with a .050 squish unless I use 50% race gas.

R Little, do you have the factory 144 or an Erick Gore kit/similar?

Darty, I looked/measured and think it may be the same as a klr250 and 650. Heading a block away to Dom's cycles in Charleston to see if the have one.

Eric Gorr...and it was supposed to be set up for pump gas.

Rattles quite a bit on pump gas 93 and still a tiny bit on 50/50.

Hauls the mail on the bottom though...it's got a 250f lower mid.

A little weak on top though.