KX500 shifter kart build

[Motorrad]

Got the engine out. Not bad for an old fart. Took me about 2-1/2 hrs. Shame on me, my swingarm pivot bolt was getting rusty and was a bit stubborn getting out. I though I antisiezed that bolt yeas ago when I checked all my s/a bearings..guess not. Got the head off and going to send it to Larry Wiechman for the decompressor mod to help "bump start" the kart easier. I also plan on  using the stock std. .4mm  head gasket (normally I run the .2mm ) . This project will be all about smooth power delivery. Piston and cyl look mint, so don't need a top end. Next step is designing an engine mount.
 

Did you tell larry you were going to use that headgasket?

he recuts them to use the .010" cometic gasket..   "squish band" wise...

[Polar-Bus]

Did you tell larry you were going to use that headgasket?

he recuts them to use the .010" cometic gasket..   "squish band" wise...

Thanks for the heads up, i've just got some basic info from Larry via email. I will get Larry on the phone and detail exactly what i'm looking for and ask the question.

[lifeishp]

how close will the chain be to the cases with that 18t sprocket ?

[flyingfitz]

I know nothing about shifter carts.  Would a rev loc clutch work in this application?

[Motorrad]

I know nothing about shifter carts.  Would a rev loc clutch work in this application?

now there is an idea.

[Polar-Bus]

Well, the easy part is done (yanking both engines). Now for the most challenging part which is engine mock up. It's a VERY tight fit with respect to the stator flywheel hitting the RH side of the seat. I don't have a lot of wiggle room as I need to factor in sprocket alignment. Kart guys discard the stator covers as they are not necessary in "road" applications. So this actually gained me about 3/8" of much needed clearence for the seat. The KX500 engine crankcase is actually not really that much larger than the CR125 cases, but the cyl is !! (duh). Here's a few early mock up pics. I sketched up the engine mount, and have some ideas as to what will work. I have a lot of scrap steel at my work, so I will be able to fab a sweet functional and rigid engine mount.







Guess it would be smart to stuff a rag is the ex port as well  huh ? Just saw this in my pics DOH stupid  !!

[Polar-Bus]

I know nothing about shifter carts.  Would a rev loc clutch work in this application?

I've always wanted to try a Revloc, but in this peticular application I will need to "bump start" my kart, so would a Revloc clutch work ? 

[flyingfitz]

Nope.

[flyingfitz]

I think you may have a hard time bump starting with those little wheels.  The compression release is a must.  Have you considered a manual type release as opposed to the button?

[Goat]

I've always wanted one of these "INSANE" toys. Only problem is there isn't anywhere near me I could ride it. Legally anyway.

Will those tires be able to handle that kind of power without ripping off the wheel?

As far as decomp I would personally go with the manual lever instead of the button. Mount it within easy reach and you wont have to reach over to pull the button. I think you would even be able to use it for a braking aid as well. Like a jake brake on a semi. Had the manual decomp on my K5 and it worked great even for braking. Fortunately I'm still young enough to kick that big bastard over without it so I don't have it installed at the moment.

[kwakman]

on the brighter side, if you dont enter the pearly gates in a cartwheeling fireball, you'll never have to listen to her indoors.matter of fact, you'll never listen to anything again!!!

[Brute]

That thing is looking great! I would be suprised if you don't get a little "pucker" the first time you feel that bomb pounding away next to you though.

[Polar-Bus]

Did a lot of research this past weekend, and asked some questions over at EkartingNews.com and got some leads on some parts that will make the swap a bit easier. There is what's called "Outlaw karts" and they are dirt and asphault oval karts that are similar to a shifter, just a bit larger. Outlaws have an "open" class that is powered by either a CR500 or KX500 engine. So looks like their pipes will work for me. I also got an email from PBI sprockets and they found a 428 pitch sprocket that matches the KX500's output shaft spline. The sprockets are actuall for an 85-00 Yamaha XT350 ! That's sweet I was worried about my custom, welded sprocket stress cracking and granading !    

Here's a link to a great selection of Outlaw kart parts :

http://www.qrckarts.com/

[RoostDaddy]

I think this is the right track, as mentioned earlier.  There are a couple companies that make these pipes for the KX, but you will find that the Outlaw guys really prefer the CR's.   

[Polar-Bus]

Well, made some good progress over the past few weeks. I got the engine mount fabricated, and it fits awesome. It's a bit heavy as I fabbed it from steel, but it won't break ! The welds are just single pass, after i'm sure everything fits there will be more welds done .







The KX500 engine fits really nice. I even have about 1-1/4" of front to rear adjustment before the magneto hits the seat.