Drag racing, yz vs wr



7 replies to this topic
  • ricky1

Posted July 02, 2001 - 08:33 AM

#1

After weeks of carb changes, I think I have it pretty good. Yesterday I was riding with two '01 wr 426's, and a cr250. We were on a dam, about 1/4 mile long, and level. 1st gear rolling start. I was a bikelength back when they took off, did a huge wheelie, caught the 426's in 3rd,caught the cr in 4th. When the cr shifted to 5th, I held it pinned until I had a wheel in front, then shifted to 5th and continued to pull away.

QUESTION: How should a yz compare to a wr, and a cr250? Should a yz beat both these bikes? We topped out at 83 mph (the dam ended). We are at 5000ft

------------------
Rick Fuller
'01 yz426
'81 490 Maico

  • firejake69

Posted July 02, 2001 - 11:09 AM

#2

I don't know very much about the WR but I thought they had taller gearing. Lets face it. YZ's Kick ass... Happy riding bro.

  • mcarp

Posted July 02, 2001 - 11:12 AM

#3

With the same gearing, equal rider and the same setup on the WR (timing, carb, etc), the WR will have a 9% faster top speed. You should be able to hit your top speed quicker, but if given the room the WR should catch up and pass you. Most WR's aren't setup nearly as aggressive as the YZ is, though.

The CR should be a little slower than your YZ overall. But it's probably 90% rider...

When I drag race a YZ426 (I have a WR400 setup like a YZ), I take him off the line, he catches up right away and passes me until around 66mph where I coast on by up to around 73. We both run 13/49 gearing.

  • ricky1

Posted July 03, 2001 - 06:06 AM

#4

I know the wr has a higher 5th gear, and a higher top speed.
Should a wr be able to accelerate evenly with a yz, up to the yz's top end?
Last night I discovered two things. One, my air filter was filthy. Two, I had the accelerator pump shut off. Zero squirt. The bike ran strong and crisp all day, no hiccup anywhere.
Does the yz426 need the acc. pump?
I don't have a better way to determine if my bike is running up to it's potential. I figured a drag race on level pavement takes most of the rider out of it, but I don't know how a yz SHOULD perform.

------------------
Rick Fuller
'01 yz426
'81 490 Maico

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  • mcarp

Posted July 03, 2001 - 08:31 AM

#5

Ricky-

No, the YZ should accelerate faster once you get off the line, but have less top speed.
The WR's first gear is 25% lower, so you are propelled 25% less in that gear. You have to shift the WR into third to match the YZ second gear (appx). So the YZ is launching you further with each RPM in the same gear. However as I mentioned the WR's 5th gear is shorter (lower numerically) so eventually the WR's top speed will overtake the YZ. Not an issue in MX where the top speed is never reached--at least by us mere mortals :)

If the WR accelerates evenly--not off the line but 2nd gear through the YZ top speed, it's either because that rider knows who to drag better than you, or your YZ isn't running like it should. Believe it or not, the rider's skill using the clutch/gas/gears does wonders. I can beat my friend when he's riding my WR when I'm on his stock KLX300.
My WR is setup similar to the YZ, but my gearbox is why I like the WR better.
He's just scared of the power and backs off to quickly when the wheel starts going up. He's a new rider, so that's no surprise.

But most riding isn't a drag race. I bought the WR mainly for the gearing, I need to chug at low rpms at low speeds over eastern trails and hit very high speeds once in awhile. I'm sacfricing the acceleration for user friendliness at low speeds and higher top speeds. Personally, the YZ's first gear is waaay off for me, too much clutch action needed to maintain slow (tight trail) speeds.

The YZ doesn't need the accel pump. But you're missing performance if it's turned off. Also the jetting may seem lean (ie crisp) in comparison. I would turn it back on unless you're diagnosing a problem.

Also, switch bikes and see what happens. Give both of you a few test runs to acclamate yourselfs to the trannies. If the WR is consistently faster, something is wrong with the YZ. The dirty air filter and accel pump would explain it!

  • WR_Jason

Posted July 03, 2001 - 09:41 PM

#6

I dont know man, I kinda think a WR should win a drag race. The lower gears mean a better start off the line, unless 1st winds out so fast its not worth the shift (12 tooth counter sprocket) and you had to start the WR in second anyway. WR stands for Wide ratio as in tranny. Lower 1 and 2 gears means better acceleration, and on top, its all WR cause of the higher final gears. The Yz has all the gears stacked close to performe better at more narrow a range of speeds with better conectivity between the gears so using just the right RMP is less critical.
I agree Its mostly up to the rider, but technicly the WR should pull the line with a good 1 to 2 shift if you can get all the power to the ground, the YZ may surge back in 3rd and maybe 4th as the WR works harder to connect those gears, but in 5th the WR should walk by. Drag racing not very relavent to overall riding I agree, but we americans always end up doing it dont we?? If it moves we will race it and bet on it. Bragging rights do rock! Most of the guys I ride with have quads so a 125 will top speed em all, but they like the hill climbs so I needed the WR 400 umphff to keep em quite. Plus puls smoking a Banshee in a drag race that a guy has like $8000 bucks into is very pleasing but being behind even one of em on a dusty trail will make you so misrible youll be right up front all the time :) .

  • ricky1

Posted July 03, 2001 - 09:55 PM

#7

I am not after bragging rights, I am just trying to get a baseline for how my bike SHOULD perform. This is really my first bike in 20 yrs, and I have never jetted a carb before. EVER. It just seemed drag racing on level pavement would take most of the rider out of it. I don't know about the other guys, but all my shifts were no clutch, full throttle almost to redline. Had to shut down at 83mph, ran out of room.

I am lookong forward to a re-match, with a clean filter and some acc. pump squirt.

------------------
Rick Fuller
'01 yz426
'81 490 Maico

  • 696

Posted July 03, 2001 - 12:02 PM

#8

Well a friend of mine has a YZ and I have a WR, who win the races......Who every gets the better holeshot! One day we were bored and decided to see which was faster, quicker, whatever. EVERYTIME we raced who ever got the jump won, the other never gained or faded. I figured the would have the better bottom and I would have more top...it wasn't so. Oh, this was when I was running my stock 14/50 gearing, I prefer my 13/50 now but we haven't raced recently.
696

------------------
2001 YR 426, YZ# Plate, YZ Fender, YZ pipe, YZ Tank, SDG YZ Seat, 13/50 Gearing, Pro-Taper Bars, TAG Triple Clamp, Moose Handguards, Maier Frameguards, Throttle Stop Trimmed, Air Box Lid Removed, Gray Wire Mod.





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