Glamis- KX5 vs the four stroke questions

[delusionised]

About jetting....and gearing....going in october to Glamis with a crowd of 450's. Last time I rode with a 172 main at 32:1 with fmf fatty and vforce reed cage. when we raced up olds.. I won some and lost some, These guys are much lighter than I (65lbs or so) and I now lost 32lbs on the atkins diet and Im down from 248 to 216 in 9 weeks. Crazy! but anyway my questions are- I want to run stock jetting at 28:1 all my other 2-stroke buddies run that and do pretty well, I was playing it safe last time and I think I lost some performance running rich. Also do you think if I raised one tooth on the front sproket would I be better off when Im pinned in 4th up olds hill? May be pulling a litte faster? Im also going to run a FMF Gnarly Desert this time. So what do you think, If i lose 32lbs, run 28:1 with stock jetting on v-force reeds and raise the front one tooth, will it be safe for the bike and get maximum performace to pull some mega bike legnths on these four strokes?  Thanks for any Input.

[Arigato]

First of all, why would you run 28:1?  According to my engine builder and several articles I've read,  40:1 will net you the most power while still giving excellent lubricicity provided you're running good oil. 14-49 or 14-50 gearing will compliment your weight loss well.

[hoopty]

I run Amsoil Pro @ 80:1 in LL100 avgas when I go to Glamis. I've had no problems at all and I've yet to meet the 450 that I can't take. I run 14/47 gearing and also have a VForce reed cage.

[doordie]

delusionised,

With that mix you lean out mainjet very much,be carefully.

It?s about how fast air travel through engine:
small bore(125cc), high rpm(10.000 and above),high airspeed,less time to attached to cylinderwall,need more oil.
3%-4%

Big bore (500cc), more air, but low speed,low rpm(up to 8000),need less oil.
2,5%-3%

//doordie

[delusionised]

First of all, why would you run 28:1?  According to my engine builder and several articles I've read,  40:1 will net you the most power while still giving excellent lubricicity provided you're running good oil. 14-49 or 14-50 gearing will compliment your weight loss well.

I was always told to run a little heavy because of the extra load on the motor.

[delusionised]

First of all, why would you run 28:1?  According to my engine builder and several articles I've read,  40:1 will net you the most power while still giving excellent lubricicity provided you're running good oil. 14-49 or 14-50 gearing will compliment your weight loss well.

what main do you run at 40:1 in the Dunes?

[Arigato]

I run a 195, but I have a ported cylinder and a bored carb.  Refer to the jetting section on this site and go up one or two sizes for the sand.  Be sure to check your plug though.  Running leaded race gas or a 50/50 mixture will be more forgiving if you err on the lean side.

4-strokes aint got nothin' for this.

[delusionised]

4-strokes aint got nothin' for this.[/quote]


 sweet bike, betcha that thing is a lethal wepon at the dunes, so i read a post here once about running 50:1 with a 172 main- thats 2 sizes fatter than stock- think my motor will sieze at this ration on that main? Thanks for your info.

[hoopty]

I've run 80:1 Amsoil Pro in LL100 with a 175 main for the past two seasons on the same topend. Get a quality synthetic oil and you'll be fine. Amsoil actually recommends 100:1  

[delusionised]

I've run 80:1 Amsoil Pro in LL100 with a 175 main for the past two seasons on the same topend. Get a quality synthetic oil and you'll be fine. Amsoil actually recommends 100:1  

wtf? 100:1 thats some crazyness must be some good oil, do you beat the 450's with your set up?

[hoopty]

All day long

[delusionised]

i love it, ill give it a run see what happens- good times!

[Timbowe]

Ams is the good oil. I've been using their Interceptor 50:1 recently, but have used 100:1 for near on 20 years with no complaints at all. {Run at 90:1 ratio}.

[Arigato]

Due to load the sand places on your motor, make sure you do some plug checks after some short runs before charging the hill.  If you're going to experiment with jetting and fuel/oil ratios, a little caution will save you some big money.  Once you have it right, go out and smoke those 4-strokes!

[BrianSM]

Plus 1 for all the above recomendations.... for 40-1 synthetic, also 50/50 race and unleaded pump, 14/49 or 50 gearing........shut the motor down immediately then check the plug....mine is tan and is the stock heat range... the green bike will beat the snot out of a red bike.....go back to all stock settings and use all the recs....play with the gearing...the Kawi people had it pretty right on....I did the full cicle and went back to basics.....