450 superkart

[Greg Cavouras]

[Greg Lindahl]

Waynes fabrication work, especially CF, is a treat!
Used to race against his sports racer and formula B cars. Although not perfect, they were very nice cars.

[Ian Harrison]

Hell Greg, I just sold a full Viper refurbed race CR250 motor with pipe, carb and ignition for less than the cost of Kyle's 450 head at 9 years ago!!!! as you say WTF!

To me, relative performance is an absolute blind alley. Once you start to compare and try to keep pace with or beat a 250 you are lost. My view is that, as a stand alone outfit, the 450 powered kart is just a waste of time and money. It appears that the vast majority agree (some with painful experience) with my perception.

Edited out (apologies - uncalled for unsubstantiated comment)

Hi Chris

A very strange post??????

OK, so you can go the route of the BSA and limit modification to try and enhance reliability and reduce the massive preparation cost to make a 450 go well, but allow an avenue for those that perceive an advantage in running 4 strokes.

We both agree that in this format the Honda is a waste of time and effort with it's fragile components as listed by yourself and compromised oiling system as observed by myslf. However after UK competitors have tried various makes it appears that the KTM is reliable in this format, i.e dosen't drop valves, snap rods or have problems with it's oiling system and has many modern features demanded by a top-notch 4-stroke race engine. The only problem I observe with these motors is the cooling/head gasket problem. Once they get that sorted it appears that the motors will be a great, reliable, fairly economical option. . . . . . but does that even matter if any 450 makes the kart unweildy and heavy on tyres and brakes (to paraphrase . "a handful") and the class has no appeal to a grid full of like-minded competitors?

Who in their right mind would want to run something that has to carry a tray to catch the oil when the motor goes boom ?? That says 1 thing very clearly:
1. These motors are expected to go boom in significant numbers regularly and often enough to require such a reg.

Or:

You can take the "Open" route which means an expensive motor purchase, loudicrously priced head (that is likely to get wrecked) as Chris' did. Stupidly priced crank/rod mods, massively priced slipper clutch, extortionately priced piston, overpriced cams, astronomically priced titanium valves, valve seats and special valve springs, etc, etc, etc.

Again this approach has also proved an absolute blind alley, but with more serious consequences. I have heard tales of competitors in the US being rarely competitive, massively unreliable and leaving the sport after being brought to the brink of despair. Edited out (apologies - uncalled for unsubstantiated comment)

Best Regards

Ian
_________________
Ian Harrison
Viper Racing UK
www.viper-racinguk.co.uk
sales@viper-racinguk.co.uk
+44 7984 225 564
+44 161 343 2009
Championship winning Superkart race team 1997-2012

[Chris Reinhardt]

[Alex Granelli]

Well things have strayed a bit . It should be a fun project. Anymore info on the adjustable rear wing that guy was running?

[Gerry MacNutt]

why not give a dual RZ a try:

[Greg Lindahl]

Hi Gary.
That's a very stout looking ride, and it looks real, not photoshopped.
I built an RZ 350 (LC in Canada, I think) powered kart in the mid '90's and was suitably impressed with its performance and reliability. And, the sounds it made were beautiful. I think the biggest issue was its weight and I recall the crankshaft was welded to maintain straightness. The class died, in the Pacific Northwest, where I lived at the time.
The RZ/LC is quite heavy. One of the fastest RZ 350 karts was rumored to weigh 600 lbs. (~275 KG).
Given that Yamaha built (builds?) this engine for so long, there are many aftermarket parts and support.
Fun stuff!
Greg

[Larry Stewart]

Now that is NUTS.
I'd LOVE to try it.

[Gerry MacNutt]

Easy to make an RZ 350 into a 500 so the would make a RZ 1000 twin

[Chris Reinhardt]

4 cylinder 1000cc, now that's just crazy talk....
2 cylinder CR500 1000cc, now that's practical
Claimed 210hp, holy crap!!!


_________________
East Coast Super Kart Series
"This is how we roll!"
www.eastcoastsuperkart.webs.com

CR2 Motorsports
"Home of Cobalt Superkarts"
www.CR2MotorSports.webs.com

[Racer Johnson]

you'll note on the rz pic above that they photoshopped out the reverse image shifter on the right and note the clutch cables and fuel lines are totally identical......

[John Benson]

Good eye Eric! Now go return you phone calls so your voice mail isn't full all the time! Oh yea, the top secret work you did in the reed area looks great. This thing is gonna fly! John.

[Sam Zavaglia]

Would the practicallity of the current generation 4T MotoX engines for our sport in competition be covered below?

Controlled engine rules bring a slab of beers for engine measuring (tech) at the end of the race meeting, going to be a long night checking the engine complies to the regulations with all those valves, springs and other sh*t to inspect.

Open engine rules bring a bag of cement dust to clean the track evertime it spills its guts and count the drivers who leave the sport cause it costs too much to repair.

In the USA, the 4T parts are most cost effective to purchase than another other place in the world.......so why have they all gone in the USA???? They have gone for a couple of good reasons.
1) Not competitive against 250 2T
2) Cost too much to repair for the average Superkarter (especially against a 250 2T).
_________________
www.samzavaglia.com

[Alex Granelli]

What are guys running primarily in the top superkart classes? Are they rs250's and other twins? How does an engine like the rz effect the balance of the kart?

[Chris Reinhardt]