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

Kelly,
I'm not talking about the white plastic retainer but there is another white plastic tube that was there also. It was definitely a throttle stop. I ditched it and it is much better now.

Yea, It was a little white plastic barrel looking thing...maybe 3/4'' long that slipped over the cable inside the spring. I guess depending on when and where you purchased, my dealer threw it away when he did the up-date kit.

Good advice on keeping track of the cable retainer plastic ring, making sure it's down and in the slot. Could get a little to exciting if not right.

the WR delivered to DR was perfect, when it was delivered to them...THEY screwed with the jetting and PV and made it run like sht, so bad it was barely ridable. i called them out on this in another thread & on their web-site and this issue was put to bed.

*

my '09 WR is rock stock, sans an FMF sparky. totally rock stock. it flat rips and all i had to do was jet it. bike came with jets (mains way too small admitedly), needles and two slides in a box. see jetting thread for more info. will the Kehin work better? maybe. never tried one on this bike so i can't knock it. the Mik works ok so far so....

the engine is an air pump. it responds to, and fuel's delivered via the carb to it for, a given TO.

you need to be specific about what it is you are trying to accomplish. having a pile of parts = frustration if you dont know what it is that needs attention and where in the circuit the issue or solution is.

i posted a thread in the common topics about how a carb works. might help yer tuning sessions in the future.

jetting aint magic. its simple physics. find the circuit for the given TO the issue is at and make a minor adjustment. one adjustment at a time.
never make more than one change at a time. start RICH, not lean.

bog/stumble = lean
gurggle/blubber = rich.

bike's gonna make more power slighty rich than lean, esp when it warms up or when air gets super cold and dense. and, itll be safe.

also- dropping the needle has burned up more pistons than lean main's so watch it! if yer leaning the circuit way out on/with the needle- STOP!
put a smaller main in and start over with the needle in the middle.
do a WFO test and check the plug.

dynos burn up engines and cant tell you how your jetting will work on the trail. they are good for finding peak numbes and values, but that's it.

dont jet yer bikes to match the performance of another brand. jet your bikes to run right and....

verify your recipe and read the plug.

Here is my setting I'll post:

09 Wr125 (stock)

Elevation 900 - 1000 ft (Illinois)

Mikuni 38 TMXX Newer Style Carb (came stock)

5.0 Slide (I had to purchase this from 04 Suzuki RM125)

Suzuki RM needle 6CHY16-62 off an 04 RM125 Part Number #13383-36FQ0 $10

Clip, Middle slot

Main 460

Pilot 45

Airscrew 1 1/2 turns

Temps running in so far: 65 degrees to 98 degrees with humidity.

Plug: NGK B9EGV

Pipe/Silencer: Stock

Walt's Powervalve spring kit - Use stock/silver spring combo. Adjusted bolt in center to 3/4 way up in slot.

Gearing:

12/50 or 12/51 for tight Harescramble courses.

13/50 for Enduros/more open courses.

Currently, 12/50 or 13/50 depending on course.

Chain: Stock O-ring

40:1 Amsoil Dominator

Maxima Octane Booster 3oz per gallon 93 Octane fuel.

No Bog,No spooge, nice brown plug, excellent bottom, mid and top end. Have a nice steady powerband from bottom to top. Great for Harescrambles.

Tonight, I will be trying the .3mm base gasket to raise my port timing and increase compression along with a new ring. Gasket was $4.75. I'll let you know if i can tell a difference anywhere.

[B]Note: I am sure that main and pilot jetting changes will be needed in higher elevations.

There are leaner needles available as well. 6CHY16-63 or the 6CHY16-64.

There are richer needles available as well. 6CHY16-61 or 6CHY16-60.

Suzuki also offers a washer and cable holder to perform 1/2 clip moves. I think the washer and special throttle cable holder are $7 each.

Would be neat if we could get some higher elevation guys/some 144 kit guys to try to master the needles?[/B]
Darin

pvduke I hope this link works as you need to study up on dynos before rattling off. http://www.land-and-sea.com/

doesn't lowering the cylinder with the .3mm gasket Lower the port timming? I fitted the .3 gasket and it doesn't expose the bottom transfer ports all the way when piston is down. May want to mill head.
Anybody checked the stock kicking compression on a 09 wr??

Gentlemen,
Lets keep this on track an useful please. Opinions are fine. Anything beyond agreeing to disagree is detrimental to the thread.
Joe

dont need to study anything, esp when it comes to dynos, sorry if it came off wrong. i know how to jet a bike for conditions, read a plug and have been doing it since 1972. that's all. and dynos dont mean jack on the trail, that's a fact. i aint PC, etc....if i come off harsh, sorry.

miss the recipe on a 4-stroke & it mostly just runs bad to a degree, a two-stroke? you can burn it up quick and i dont like seeing my buds bummed w/o an engine or a ride.

more importantly, i'm here for anyone that might need help with same, i aint here to bash. PM, e-mail or call. anytime.

-kevin.

No problem duke. I myself am constantly learning and do need to study even things I thought I knew. True that nothing matters in the woods but a good running machine that won't burn up. But I disagree that the dyno is only usefull for numbers and not tuning. It is also a safe way to find answers I was just not getting by riding. I thought I was correct in opening the pv early and dead wrong, rich on top with a 460, wrong again and the list goes on.

Dynamometers are just tools. Like a file, wrench or screwdriver they can be used correctly or not.

I used to use one to tune RD350’s and RD400’s for road racing back in the mid 70’s. We used to do runs based on RPM, throttle opening and gear ratio, as all these are independent variables. The resulting data were loaded into my Ohio Scientific Superboard computer and 3-dimensional plots on my Gorilla Banana printer (anyone remember these?) were produced and analyzed. The goal was to tune for plots of the largest volume. This essentially made sure we were getting the most useable hp/torque possible no matter what gear, throttle position or RPM we were running. Kind of like the fact that 250Fs will beat 144s even though they have less peak hp. They simply have more area under their torque curves = they have more useable power.

More than just carb jetting went into this. We altered ignition timing, jetting, porting, final drive ratios and even exhaust tuning. Although since this was “production racing” the pipes had to look stock. That was fun. This took literally hundreds of runs on the dyno. Luckily I worked for the shop that owned it!

For those of you with a hp fetish, get over it. It is not the most important thing.

In my case, the limiting factor was rider skill. My bikes went like a bat out of hell; I went like a slug on a cold September morning. Story of my life...

Dartyppyt
I am really happy for the time you put on the Husky, fore mine runs absolutly great now

Thanx Team,

That is why it took so long to hit the right combo because I had to keep switching mains and etc... I basically jetted to the slide and the needles. Another factor was to use parts we already have. A 2x4 is cheap till you buy all the screws,nails,hinges and etc...

I agree, No matter who does these changes, always watch your plug for a while. In fact it doesn't hurt to put a new plug in at the get go to get an accurate plug reading. Yes, you are right, I lowered the port timing with gasket and raised compression. I used to cut some off of piston skirts, stack base gaskets and take some off the heads back years ago. Talking to Mr Hall, he recommended this for a little more bottom. I will let you know if there is a $4.75 worth difference, but will be hard to tell with the new ring. I put it back together last night and did a couple heat cycles to help break the ring in. I can tell just from the kick starter that I do have a little more compression. I think it's mostly due to new ring? Then too, the bike only had under 15 hours on it, but I had wet plugs/lean plugs till I hit the right combo. When it was lean I could have lost some temper in the ring. I was really impressed that all the cross hatches on the cylinder were still there, the power valves moved easy, the piston looks like new, and had hardly any carbon on the top. I have been trying the Amsoil Dominator, from Kelly's suggestion, long time ago, and seems to keep the power valves moving better/cleaner.I sure miss the castor smell! What will be interesting is the fact that high temps racing tomorrow will be 56 degrees. I'll let you guys know what I learn. One thing, my fuel consumption has gone up a little and don't think I'll make it on the stock tank for 1 1/2 hours, so I am stopping for a gallon shot of Amsoil Tequilla! I want to purposely see if I can stay behing a 250 four right before a long straight away to see how they go against each other with the RM needle.

Thanx!

Darin

BillO, see if you can get a cheap airline ticket. I will pay.

Thanks for the offer gsxr100user, but it's not a money thing. Money I have, time I don't.

Once my son was out for the season with injuries, the better half arranged a number of projects we've been putting off for a few years.

I'm roped an tied.

Darin

Did you check the squish when using the thinner base gasket ?
( I am about to do a top end rebuild and was going to use a .3mm gasket as well) My compression is at 135 after 35 hrs ish.

What I dont get is how the RM needle affects the top end WFO ?
If you look at the following chart


View attachment 6674

Good question about WOT with RM needle. Does the needle come all the way out of the main jet. What about the straight diameter of the needle ? What does it affect

I just wanted to say that I am very, very, very, happy with this bike. I raced it yesterday (45 degrees out when I left the start), the first time since May, without the bog. I got a good start, was really crisp (no carb load up) in the woods, ripped down the straights and impressed the spectators on a long steep hill (I would ride a wheelie towards the top). Don't even ask me how I finished. I pegged two trees head on, bent my fingers back on my left hand, have a stiff neck/sore shoulder from landing on it, twice, nice dent in my pipe and broke my left radiator cover.

I had a great time, the bike raced the best it ever has, and I even got the chance to lap my son on his RM 125 at the end. He looked back, saw me behind him at the check point and I passed him on the next long straight away. Believe me, he had his RM pegged! I teased him the whole way home that he needs to buy a Husky!

To answer your questions: The .3mm base gasket? I think it helps, but is hard to tell with the new ring in, but it's on $4.75. I think it helps with the throttle response. I don't not know what the squish is. When I ringed it friday night, I was in a hurry and did not take the head off when I pulled the cylinder. There was no carbon on the head.

The needle question: The needle is thinner at the top. Your going from .74 to a .62, it has a nice thin taper all the way to the bottom. The bottom of needle is thinner as well. I think the needle size/the taper/5.0 slide work very well.

Thanx!

Darin

Update on jetting:

I rode some Saturday morning to breakin my new ring. I figure it would be about the same temps as yesterday. It was in the 40's Sat am, so I decided to try a 470 then 480 main. Yesterday, I got a chance to take a couple long distance runs before the race, checking throttle whack and high top end. I went back to the 460 main with the best results. Air screw is still set at 1 1/2 turns out.

So far the the 460 main is working from 45 degrees to high 90's.

Tune/test question-can't wait!

I've been too busy with work and summer play to tear into my bike-also am spending a few days up near Pittsburgh to see my son, a senior in High School-he blew his knee out in football and just had surgery...I promise to post what I find but wanted to ask: What do I do first-mess with the PV (I've got the kit) or tune the Mikuni with the "RM set-up?