All 2st About the Mikuni/Keihin swap:

I had a #7 in my WR250.

Walt

They spooge when u lug them and the silencer does not get hot.

It's not really a jetting thing.

Thanks for the guidance on spooge

I had removed the clamp that was around the rubber sleeve at the pipe/silencer joint and used zip-ties which caused all the spooge to drip from the junction onto my swingarm. I had two separate guys on the trail look at it and say it was too rich but I had looked at the plug and it looked good-I thought I would mention the spooge and see if ya'll thought the same. Hey, I'm thinking about not trying to seal that sleeve completely-it's saving my silencer packing from getting soaked-whatya think about that?

I run Mothul 800, what do you think about it ?

My other bike was a spooging mess until I got the squish band corrected in the head. No amount of jetting had any effect on the spooge, but once the head was cut the spooge was gone instantly. And now it doesn't spooge at all even when jetted rich.

In my case the squish was too loose and not allowing for a hot enough burn in the head. It was hot enough to burn the fuel, but not the premix oil which ends up getting pushed through the exhasut, saturates the packing and then dribbles down the silencer.

Also, if your silencer packing is already saturated then you'll never know if the spooge is truly gone cause the exhaust pressure will just keep pushing the saturated oil out the endcap.

My worthless 2 cents rofessor:

Depending on how perfect I have my jetting I get from very little to no spooge in tight woods. This involves being off the pipe a lot of the time and I run my oil at 32:1. If the squish is correct and the jetting is sharp the bike should not be creating a lot of spooge. Not that it really matters if you have spooge or not, what matters is how it runs. I jet by feel but that generally gives very little spooge.

My current setup is a 36mm PWK. 42 pilot, JD Blue #3, 6.5 slide, 162 main. Squish at 1mm. Fuel is 50% Avgas and 50% pump slop. Oil is Castrol synthetic but Amsoil worked about the same.

My bike was way lean the day you rode it as I was not expecting 20 degree temps. It was so slick it took me a while to notice it was not pulling very well.

It normally pulls better down low but never has a bunch on top. I think the 36mm carb has most to do with that. I really want to try a new 125 if it can have good low end and still scream on top!

I imagine I would have to go up at least four sizes of main if I had a 38mm. Also the Avgas makes it need about one step leaner.

Well i got my wr 300 back together after I had RB do the carb and head mods. I was pretty frustrated with the jetting . I went back and forth with the red and blue ,no luck. I worked with Ron and he came up with the kehin CEK neddle , presto , The thing runs like a true big bore bike. I could not be any happier. Jet specs 42 p, CEK #2 172 main.

I'm gonna have to try that needle. Is 'CEK' the entire needle designation?

The complete part # is N427-48CEK

On my WR250 the cel and cek needles both worked better than the JD needles On my WR144 the JD blue needle works a trick. On the 250 I did end up going with the CEL needle which has a slightly larger base and allows you to control the very bottom end with the pilot and air screw a little better than the CEK. It worked great at ST. George Utah too which is only about 2800'.

Walt

Woodschick,

The Keihin carborates so much better on its small throttle opening circuits that you can actually control the jetting here and get it spot on. I just could never get the Mikuni to do this for two days in a row.

Walt

Lot's of good info

I don't think I'm leaking to the point of losing back pressure cause the spooge is just dripping down from the rubber sleeve. I'll have to let her rip on top and see if I'm getting any spooge blown out. When it's time to do a top end I may get the squish correct. I'll be riding again this weekend and...man this 125 is so much fun! You guys are just a wealth of knowledge...I appreciate ya!

Thanks!


And for the poster whom stated about the pipe silencer junction leaking spooge. TM Designs sells a nice billet, triple o-ringed seal. I got one on another bike and it really did keep that junction clean until I was able to truly rememdy the spooge situation. I think its one size fits all and costs about $30. That is, if I remember correctly from 4 years ago....