KX Guru Racing

jgturbo

Still a little curious: Where's your fire ring?
Here's how I do copper head gaskets:
Make a cutter like this:
Spin the cylinder (or head) like this:
End up with a groove like this (.031" wide, .020ish deep):
Tap in stainless wire (.032" dia):
Design and waterjet a gasket:
Coat with Hylomar and install:
Then boost the heck out of it!

Motorrad
Oh wow... That is SEXY.
No fire ring on mine...

jgturbo
Haha, no. I wish. This was a turbo SV650 engine (sleeved to 606cc) for a FSAE car. Didn't see much boost, however. The rest of the car never really got completed. Ran good on the workbench though! rolleyes
This had a .024" gasket with the o-ring up .012 off the deck.
Motorrad, I've never heard of using a copper gasket w/o a fire ring. But I'm new to 2-strokes engine building and, looking at the rest of your work, I'm sure you know what you're doing!
Is that normal to do on a 2-stroke?

81cr450
Stock air-cooled 1981 cr450r used a copper head gasket without a fire ring from the factory. no water jacket though. Copper coat is your friend on liquid cooled no o-ringed 2 stroke running copper, my 2cents.
RoostiusMaximus
its embossed

81cr450
Not after I reused for like the 5th time

Motorrad
Rode to gun store to buy my shotgun. Buddy there summed up the bike for me.
"550 nitro express".
If you don't know your gun rounds look up .700 nitro express
Bloody he'll it's fast

Motorrad
Okay dragging Reeds back up to the surface..
Im seriously thinking of running Kx250 reeds (the ones in the picture) with the stuffer...
some numbers to chew on..
All numbers are area rough....
44 mm Lectron output hole (motor side 42mm hole) = 2.1474 sqin
Stuffer in 87 reed cage (same size as square hole in rubber intake boot) = 3.168 sqin
Kx250 stuffer = 1.9704 sqin (same as a 40.5mm carb)
so its obvious the kx250 stuffer is much closer to the same size to keep velocity up than the stock stuff.. and with a bit of masaging, could be the same
If I modify the crapola out of the Half a Rad valve I have.... or it would actually be easyer to just make a new intake like BDI's (search for it people).... it would all bolt on without the MASSIVE volume change going to the motor.

Thoughts.

Brute
None except they would make cool napkin holders!

RoostDaddy
maybe look into the jetski reed cages "I know" there is one that will fit. If you have the tabs cut off your stock intake boot, no worries because this cage has a built-in stuffer. Now you can massage it all you want.

Motorrad
I know everyone was running cages off the 750 jetski for a while.. (the Vforce) before they were offered for the K5..
which cage are you talking about? The M-16 cages?
I know of these
http://jetskiperformanceparts.com/index ... ct_id=1350

RoostDaddy
Stock cage with built-in stuffer. You need to put better reeds on it though, the stockers dont seem to like a 500.

Motorrad
if its the cage Im looking at (stock ones out of the 750 and 800 ski) the intake hole looks the same size in that stuffer as the 87 cage.
which is where I see a problem. (in my head)..
the hole is HUGE.... compaired to the carb etc..
I dont have a flow bench etc. but in my head.. if you have a 42mm carb outlet.. keeping that same 42mm volume all the way to the reed tips makes sence. Am I wrong? Could be...
But I think this is why BDI and Doordie were seeing such great results with the 250cc vforce cage.. The K5 like its transfer ports, may be over reed/intake boot volume'ed...
Thoughts?
This is a discussion people... jump in...

Motorrad
Okay... here ya go... (rough.. still need to smooth out and de-bur)
42mm (volume) from carb to reed tip....
Kept the general shape of the rad-valve... as I believe it did compensate for the curveed boot.. just larger now... (reason its not true hole at reed side)

Motorrad:
actually to be honest... I think Im going to de-tune her slightly...
good gas is getting hard to get here local without $$$$$$$$$$$$$ so going to re chamber the head to "get away with" premium.. but have it love to run a 25/75 mix. (like your bike oscar)

USMC 500:
I myself am running a 50/50 mix right now.......but the "secret squirl grin" fuel I use is $5.50 a gallon where I get it so I might change that up myself.

Motorrad:
same fuel I was running also.. same price.. but... alas.. the Terrorists have won.... and its hard to get now... next cheepest option is $12 a gallon.... and that hurts when your bike is tuned to run it 100% straight.

USMC 500:
Ok, big deal, detuned you are going from 90 hp to 85 hp........I'm sure that will make it much more managable.

Motorrad:
No pictures... but..
Motor was out of bike ............. cases split. new seals and mains installed.
put back together. and is now back in the bike......
Head is off. waiting for me to finish Modifying my head gasket rolleyes ....

USMC 500:
do you realize that you split cases more often than most people change oil?! shocked And in some cases.....faster.

Motorrad:
Cases havnt been split for ?2-3? years. and LOTS OF FUEL..

USMC 500:
some people don't change their oil for 2-3 years....... undecided

Motorrad:
well good for them.. undecided
Headgaskets made. and installed.. head is on.. grin
Now at 13.5:1 (uncorrected ratio) instead of 15:1 like I was

USMC 500:
So no more running "secret squirl" fuel 100% straight? You gonna mix 25/75? Lets schedule a ride. grin

Motorrad:
yes. getting swcret squirel Juice is getting rough..
I may have to run 50/50 still with all the port timign im running vs you "stock" guys... wink

sandblaster:
So, do you have a ride report yet? grin

USMC 500:
Hey, my bike is NOT stock....for your information I have a pipe, silencer and VForce 2 reeds.... grin cheesy

Motorrad:
AND your port timing is raised .020" whoop! whoop!
and dont forget yoru lowered exh port.

USMC 500:
SSHHHHHHHH!! What the hell?!.......don't give away all my secrets........now I'll never get rid of the trolls!! rolleyes

SHLEPY:
ALL RIDES MUST BE ON SUNDAYS.....I got suckerd into coaching again and I got 2 games every sat for the next 10 weeks undecided

USMC 500:
You got it boss.....you let me know when is good for you and I'm there.

SHLEPY:
LOL Oscar you been promoted from Flacid to Giant member.

USMC 500:
OH....there have been many changes in the past few minutes....hahahaha. I think my profile is having an identity crisis. cheesy

SHLEPY:
Ya I see the R then its gone.

USMC 500:
You mean the "R" that is currently there? cheesy
And i think motorrad is pissed at himself......for some reason he is "Banned".
It must be cold where you are at Shlepy.....hahahaha

Motorrad:
Kinda Cold out... Eh Shlepy? grin

SHLEPY:
HAHAHAHA YOU FOOL LOL.

SHLEPY:
To funny

USMC 500:
I'm offended......my grandfather died in the holocaust
And there goes that "identity crisis" again.

Motorrad:
wrong war tongue

SHLEPY:
Wrong war! grin

Motorrad:
haha beat ya by 18 seconds!

USMC 500:
I'm so glad that Motorrad's Jeff Ward motor thread has managed to remain so informative and productive. grin

SHLEPY:
lol you girls are to much,im out nighty night.

USMC 500:
Hey come back here and fight you coward....we're not done yet.....we got unfinished buisness!!! cheesy

Motorrad:
those were my grandfathers last words... before I died in the holocaust...

USMC 500;
Wrong war........ rolleyes
hahahaha.....2 years and 2 weeks after the beginning of this thread and this is what its come to.....

Motorrad:
Your just jellous that it took me less time to do that than it took you to change an airfilter...
And it would have been done faster If I wasn't sick most of last week

USMC 500:
Hey, it was a really dirty air filter. Once I pulled the air filter I could see just how dirty the kips drums were. grin

Motorrad:
Just Compression tested the OL girl for a baseline to take notes on with new lowered compression ratio.
195PSI. even with my port timing.. and dropping the compression ratio a point and a half... d**n my foot hurts. undecided

SHLEPY:
LOL Tammy said you need a big boy like me with some ass to kick it over for ya. evil

USMC 500:
Shlepy "barefoot" kick starts bikes that Chuck Norris is afraid to start!! shocked

Motorrad:
I think danny would appriciate being on a team green, street legal KX..

USMC 500:
You bet he would......looking good brother!!

sandblaster;
I'd appreciate it too shocked

Motorrad:
Modified the choke on my lectron today.
Most say you dont need a choke with a lectron. well my bike does. and the standard lectron choke SUCKS BALLS. its on the wrong side, so you have to reach in past the pipe to turn it on... AND THEN they dont stay on... nope... just fall back down. a bit too easy.
so.
little modification of the Original choke shaft. some doner parts from a Mikuni carb. and whala.
And a few "other" forums said it cant be done. rolleyes

sandblaster:

That's because most sites don't know a Motorrad from a mouse smiley
How many times have I read this thread?
I don't know but, there is more hidden in plain sight then first meets the eye.