Tuning/Jetting/Spooge

Chili

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Apr 9, 2002
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I'll start this thread by stating I have done many searches and read all sorts of threads on jetting and spooge but I still have a few questions and hope you all can give me some help.

I am dealing with 2 bikes, my 86 RM125 and my son's 99 KX80. Both bikes were bought used and have been great purchases in my mind but the subject of jetting has me thinking if they can't be even better bikes. Based on Rich's assertion that only 1 in 20 MX bikes is jetted even close to correctly I figured the odds I bought two of the rare breed is pretty slim so here is the facts/info at hand.

Both bikes are being run on Shell premium pump fuel (91 Octane) and using Yamalube 2 the, KX gets 32:1 the RM 20:1 both on the manuals recommendation. Neither bike has any stumbles or bogs in the throttle other than the RM125 at bottom end but I figure that this bike didn't have any bottom end from new likely either and runs fine if I keep it screaming. The KX80 has some mild spooge leaking from the rubber cover that covers the head pipe/silencer joint. The question becomes even though the KX can rip through the gears without any stumble or hesitation and the throttle response seems good do I still toy with the jetting for spooge elimination? Or is it possible it can run even better even though we don't find any stumbles in the throttle response and are just not experienced enough to know how much response we should be getting. And if I toy with the jetting where do I start since there is no noticeable flat spot or bog? I've also considered trying other oils once I run out of this case of Yamalube but don't really want to go to the $15 a liter Torco or other fancy race oil. I've yet to find the Mobil MX2T (I think) that seems so popular on this board anywhere in my Canadian city. There are a few Maxima retailers here though so I've considered trying the Super M based on what I've read on this board.

I also know from reading other threads that "chasing spooge with ratio" is foolish but would it be an appropriate time to do so when your throttle is crisp and you've still got spooge?

Sorry for the long post I can't seem to post anything without it becoming a looong post lately :silly: All opinions and time taken to read this post are appreciated.
 

Durt Cycler

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Nov 13, 2001
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The KX is good at 32:1 and the RM will run cleaner/crisper with a 32:1 ratio also. I experienced this exact same problem after I dailed in my CR125s jetting to where I had a tan plug at every throttle position and crisp response with no bogs or surges, I had a tiny bit of spooge leak from the silencer and exhaust manifold and experimented with different oils to try and lower the spooge. My results were....

1st. Yamalube 2R - spooged alot and throttle response wasn't crisp enough, and was smoking alittle

2nd. Klotz BeNOL - throttle response suffered in the bottomend, bike smoked some if I was at low RPMS, burned dirty if I didn't keep the RPMs up, and spooged alittle more then the Yamalube if I did slow trail riding

3rd. Bel-Ray H1R - Response was crisp but still had minor spooge and almost no smoke

4th. Maxima SuperM - Response was crisp and had almost no spooge but a light mist which wasn't nothing compared to what the other oils did and almost had zero smoke but only at warm up it smoked. I found SuperM was the best oil to run in my bike and was almost the cheapiest
 
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gooby

Member
Nov 8, 2001
497
0
i think ur real close on both bikes.if it aint broke ....no fix :) how bout a spark plug with a finer electrode? my kdx i ran a br8es ,now a br8eg,cleaned up low speed/off idle running ?i use mx2t and it's a great oil ,my bike runs great,plug color perfect,not much spooge.i'm bummed i got nothin to mess with lol.
 
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