quadzilla vs. kxf250

quadzilla vs. kxf250
Posted by 87zilla on 23 Aug, 2014 21:50
I raced my buddys 2011 kxf250 and my 87 zilla, has hot rod crack, bored .80 over, ported and polished, 40mm carb, full fmf exhaust, 14/38 gearing and i got beat 3 times by about 2-3 bike lengths, was on a gravel road. shouldnt the zilla of ate the kxf??

#1 Reply
Posted by El Diablo on 23 Aug, 2014 23:17
I like the gusset work on your frame. Was it converted over to the 88-90 A-arms?
Back to your question, you might want to try a bigger rear sprocket like a 40 or 42 then try the race again. The FMF is not a drag race pipe but is not POS either. Just make sure you are running race fuel & that your carb is jetted accordingly. You didn't mention whether or not you was running an air box & lid or not. This makes a difference in output. Also, those dumbo ear front fenders probably slow you down quite a bit.

#2 Reply
Posted by 87zilla on 23 Aug, 2014 23:41
Im not to sure if it was converted, and no air box lid, also it had just regular fuel in it mixed 32:1 does it make that big of a difference? and the front fenders i dont even know what to do with them lol when i ride it its like there trying to fly away

#3 Reply
Posted by PCS on 24 Aug, 2014 06:26
Pump gas on a zilla is a quick way to trash your engine, prone to detonation with pump gas. Hot rods crank doesn't make more hp than stock so you can count that out, it's been heavily discuss that boring out didn't really help much to make extra hp.who ported the engine and do u have stock reeds?
What is done to the dirt bike?
Is he a better rider?

#4 Reply
Posted by Buckeye513 on 24 Aug, 2014 09:42
I only lose to built 450 bikes by about a bike length every time I line up with one on dirt so no you shouldn't have lost IMO even with your setup. On gravel that's deep I roost the **** outta 450's.

#5 Reply
Posted by 87zilla on 24 Aug, 2014 10:09
Has fiber reeds and im a better rider, tops out at 80kmh in 5th gear,

#6 Reply
Posted by Buckeye513 on 24 Aug, 2014 10:20
80 kph??? That's extremely slow for a Zilla blasters go faster then that.

#7 Reply
Posted by Cunningham_821 on 24 Aug, 2014 10:39
Imo being 100 percent honest you will have a very hard time out running a bike... Even if it is half the displacement... The reason is rotating mass and total weight. Yoy are racing a 220 lb bike turning a wheel thats 3 inches wide vs a zilla thats 400+ and turning 4x the weight in the back plus pushing 2 wider wheels up front.

#8 Reply
Posted by 87zilla on 24 Aug, 2014 10:41
90kmh ** has 16or 18 inch rear tires, idk its just really slow, could it be the front fenders holding it back that much? Cuz when i drive it the fenders almost like fly away lol

#9 Reply
Posted by Cunningham_821 on 24 Aug, 2014 10:42
Dont take offense to this ive been racing a while now and ive lined up against all diffrent types of bikes. And this is the conclusion if come to...

#10 Reply
Posted by 87zilla on 24 Aug, 2014 10:50
Runs great and everything, has power all the way through, just doesnt go as fast as it should and idk why

#11 Reply
Posted by Cunningham_821 on 24 Aug, 2014 10:53
Dude if your running 18" with that gearing then there is ure problem that ratio is 2 low for 18's go like 15-40 your at about a 2.7 ratio right now id get down in the low 2.6 range.

#12 Reply
Posted by 87zilla on 24 Aug, 2014 11:00
Ill try changing the tires, fenders and running race fuel and see what it does!

#13 Reply
Posted by Glamisrider on 24 Aug, 2014 12:09
You also forgot to mention how long the length of the race was.

With that gearing in a long race (all top end) I'd imagine you'd beat his top speed.

In a short race (especially with the stamped FMF) I'd imagine he'd beat you especially with that gearing. In a short race it all about out of the hole and with that tall of gearing I'd imagine he got you out of the hole and kept it to the finish?

P.S. the FMF Stamped pipe falls off in the top side of 3rd gear, at least this was my experience.

#14 Reply
Posted by PCS on 25 Aug, 2014 05:04
Stock zilla can do high 70s mph.
I've dragged raced a handful I'd dirt bikes on the sand and it's rare to see them keep up. With an 18 rear tire I would add a tooth to the counter sprocket.

#15 Reply
Posted by Petenorth on 25 Aug, 2014 18:50
The front fenders isn't the problem. Dirt wheels test a stock one with and without plastic in a 1988 issue and the difference was very minimal.

#16 Reply
Posted by Motoman991 on 26 Aug, 2014 10:58
Something seems wrong with your zilla if you lose to any 250 four-stroke bike.

#17 Reply
Posted by Zilla273 on 27 Aug, 2014 04:45
My bartlett 250 runs neck n neck with my buddys 01rm250,should beat it id think, but never drove one with fmf though

#18 Reply
Posted by Q2W on 27 Aug, 2014 07:12
Yea, a zilla should never lose to a kxf250... ever. You got some issues somewhere. Either jetting, gearing, deto, etc.

#19 Reply
Posted by ZillaFreak on 08 Sep, 2014 08:43
a stock 250? i have ridden a buddies yz250f, it had some mods and it was quick.

on dirt, a good rider on a bike can get out of the hole fast.

was the race on dirt or what?
length of race?
skill and weight of each rider?

are you spinning off the line?

#20 Reply
Posted by 87zilla on 08 Sep, 2014 21:28
So found a few things, about a gallon of antifreeze in the oil, loose reeds(which caused screw to fall out and lock up the motor later that week) dragging front brakes really bad and and a few other things

#21 Reply
Posted by Yagerzzz on 09 Sep, 2014 10:22
An '87 Zilla with the slower external gearing was verified to go over '79 mph years ago in 3&4 wheel action.

About 10 -15 years ago, My bone stock '88 zilla out ran a Honda XR 350 enduro bike on the street, even at top speed. We were trying to use the enduro to check the top speed of the zilla. (We didn't have GPS back then.) The first time we ran, I took off and he never caught up so he couldn't tell me how fast I was going. So the next time, He started out about 1/8th mile behind me, and I waited for him while he got up to speed and when he got close, I took off. He still never quite caught me. At one point, he was within a couple bike lengths but I was slowly pulling away. His speedo was topped out just a tick over 80. I was going roughly 81 or 82 according to that if the speedo was correct.

And an FMF pipe on a zilla is junk IMO. The FMF's for 250's are ok, but I'd rather have a stock pipe on a zilla compared to an FMF.

I also new a guy years ago that had a zilla and two YZ250's. He said the zilla would spank them both. I couldn't believe until we rode them in a grass field. Holy crap, the zilla was fast. He was right about it beating the YZ's. It was a time bomb, but it was fast as hell. (Idling, it would overheat and leak antifreeze.) I think it had an LRD or trinity pipe. Nothing special by todays standards.

If a 250 four stoke is even close to you, you have serious issues with your zilla and your loosing the traction war. Race on pavement or hard packed dirt to make sure your bikes at least outrunning his. Then you can try different tires / gearing to figure out how to win in the loose stuff.

#22 Reply
Posted by 87zilla on 11 Sep, 2014 14:27
Race was on a gravel road about 1/4 mile, raced 3 times, both riders about the same weight and spin on take off.