info on getting jetting right from JDean re vibes

[Simmo737]

This might help someone....

what i wrote:

G'day James

I purchased your kit for my 2011 gg, (the newer kit) and it works great! I have 300 with the 36 mm as2 carb which looks like the pwm on my 98 rm125 but with an idle screw separate from the choke pull.

I've put an S3 head on the bike, which takes the squish from around 2.5mm to 1.5 mm and has a slight increase in compression.

I'm sea level to 2000' 10 deg c to 35 deg c I've been using 38 blue 4 172 7.5 mm float height, after a dealer recommended that increased compression needs a richer setting.

Today I decided to try the same 38 pilot, changing to blue clip 3 172 main, the bike vibrates a lot more than clip 4 and has a lot more grunt and revs faster (it completely rips so I'd like to keep this setting). Slight spooging in both settings, little smoke, using 40:1 Amsoil interceptor. Water temps are similar. Idles pretty much the same (good). Tiny sputter with the throttle barely cracked both settings, very slightly less at clip 3.

I'm staggered at the performance change in 1 clip.

My question Is regarding the noticeably increased vibes on clip 3 compared to clip 4, could that indicate a too lean condition? Also am I on the right track enriching for the extra compression? The bike does not seem to color up new plugs much at all, but gives a good electrode burn pattern, older plugs seem to color up ok.

Cheers and thanks in advance

What JD wrote

Mike,

Yes, you are on the right track using a slightly richer jetting. The vibration is indicatiing you're making more power now. The jetting sounds close to perfect, and I'd suggest comparing the Red needle in clip position #4 from top to running Blue #3 clip position. The #38 pilot jet is a good setting. The main jet can be lowered a step or 2 with the 36mm carb, to near #168 or #170,-if you find the bike runs rich when you open it up after riding in slower conditions and find that the motor doesn't clean out quickly.
Thank You,

[Jakobi]

Good info Simmo! Braap braap! I have also noticed a clip position has a big effect on power, but even more so a big effect on fuel consumption.

[Simmo737]

i think when you get everything close, all the jets, slide height, float height, needle, good fuel, good filter, correct throttle freeplay, one notch is a big change, at least it was for me..wow

ill get the gopro out after we get back from hols in a couple of weeks and shoots some vids trialing around in a gully, i just got home and did some just then and the bike is finally completely dialled, suspension front and rear, jetting, bibs and bobs.... this bike flat rips...bit disappointing really, luckily I have the rm125 to dabble with..one last load of parts and it goes back together as well though.

[Jakobi]

I'm in the same boat. Have run out of things to do to the gasser. I might try one of those arrow expansion chambers if I can get one for the right price.

Just bought some new parts for the WR250F. Will be giving it a freshen up and then I don't know what. Maybe a yz 125 or something..

[Simmo737]

125s are the bomb, always on the pipe, noise and commotion, then you look down at the ground and realize your not going that fast, nothing makes you a better rider than a 125.