KX Guru Racing

Ok, it's not a KX500
But I have some reasons to see what we can do with this set up.
No, I'm not talking about why just yet
I know what others are claiming but that only holds so much water with me.
What is real?
We shall see.

2016 KTM 300 XC with a SX head.
First off we needed to see what this baby was making at the rear wheel.
So we went to our friends at Motogear in Eugene, Oregon and they ran it on their dyno.
48.11 HP at 8,040 RPM
32.49 Ft lb of torque at 7,680 RPM
Not bad for a cute little engine

Getting it dialed in..

After spending some time on the porting table this case went through Vapor Blasting and is in the oven drying..

A little more progress..
One crankcase down and one to go.

https://www.youtube.com/watch?v=BX68q_y ... e=youtu.be

My thoughts on the KTM 300 cylinder and porting..

https://www.youtube.com/watch?v=Wwn7FWg ... e=youtu.be

Crank as measured before disassembly and modifications

The crank dimensions are
Outside to outside
2.354 in 59.80mm
Thrust washer clearance
.0200 in .51mm

Ok... I have a bit of polishing done.
I can't get into the groves but that it will make no difference.

Here's the wheels the customer bought.. Yes, two sets... Tommy is almost as crazy as I am

This engine was gone through and has a new top end.
Reed: V-force 4
Carb: 38mm
Pipe:
Counter sprocket: 14T
Sprocket: 51T
Bore: 72mm
Stroke 72mm
Center to center of connecting rod: 125mm
------------------------------------
.030" base gasket
Piston to deck height: .013" OR .33mm
Top of the exhaust port to the deck 39.1mm
Exhaust port timing: 187.96 degrees
Transfer timing bottom: flush with the top of the piston (depending on the base basket)
Rod length center to center: 125mm
------------------------------------

22.5cc head volume (SPECIAL)
Piston to deck -1.35cc
Head step: .045"
Step diameter: 2.844" 72.25mm

.030" base gasket
Compression specs:
Uncorrected 13.1:1
Corrected 7.68:1
Calculated cylinder pressure at sea level 192.57 PSI

.009" base gasket
Compression specs:
Uncorrected 14.87:1
Corrected 8.53:1
Calculated cylinder pressure at sea level 218.59 PSI

"0" base gasket
Compression specs:
Uncorrected 15.51:1
Corrected 8.88:1
Calculated cylinder pressure at sea level 228 PSI

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23.cc head volume (SX)
Piston to deck -1.35cc
Head step: .060
Step diameter: 2.844" 72.25mm

.030" base gasket
Uncorrected 13.05:1
Corrected 7.54
Calculated cylinder pressure at sea level 191.84 PSI

.009" base gasket
Compression specs:
Uncorrected 14.55:1
Corrected 8.36
Calculated cylinder pressure at sea level 213.88 PSI

"0" base gasket
Compression specs:
Uncorrected 15.16:1
Corrected 8.69:1
Calculated cylinder pressure at sea level 222.85 PSI

---------------------------------------

24.5cc head volume (XC)
Piston to deck -1.35cc
Head step: .075
Step diameter: 2.844" 72.25mm

.030" base gasket
Uncorrected 12.35:1
Corrected 7.16:1
Calculated cylinder pressure at sea level 190.66 PSI

.009" base gasket
Compression specs:
Uncorrected 13.67:1
Corrected 7.88
Calculated cylinder pressure at sea level 200.99 PSI

"0" base gasket
Compression specs:
Uncorrected 14.2:1
Corrected 8.17:1
Calculated cylinder pressure at sea level 208.74 PSI

1st run I want to use the .030" base gasket and the XC head to give us a base line.