QUESTIONS ON 1998-99 YZ400 PROBLEMS

I HAVE BEEN READING ABOUT THE YZ400'S FOR SOME TIME NOW AND I AM THINKING OF BUYING A USED ONE. I HAVE HEARD OF SOME PROBLEMS WITH THEM AND I WANT TO KNOW IF THEY ARE TRUE AND HOW OFTEN THEY OCCUR. I HAVE HEARD THAT THE WATER BUMP GOES OUT SOMETIMES AND THAT THE CRANK SHAFT WILL GO OUT AFTER A PERIOD OF TIME TOO. IF YOU COULD HELP ME WITH YOUR IMPUT I WOULD APRECIATE IT.

All you have to worry about is the 98's

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I am 5'8 155 on a 426.

I am nuts!

Livermore Ca

wots wrong with the 98's?

Had no problems at all with my '98...

THANKS FOR YOUR HELP! I HAVE HEARD A LOT OF DIFFERENT WEIGHT NUMBERS OF THE 400'S FROM 236 (WITCH IS NOT TRUE)UP TO 260. I KNOW THEIR AROUND 260 BUT I DONT THINK THEIR THAT HEAVY. IF ANYONE COULD TELL ME WHAT THE WHAT IS FROM THE SPEC BOOK I WOULD APRECIATE IT.

The only problem I have with my 98 is it doesnt like to stay behind other bikes,it insists on being in front. Me and betsy have a good open relationship and I agree to let her lead and she agreed to a bath after every ride. Besides that she only has a drinkin problem. Jeff

My 98 was 251 lbs ready to ride, no gas. 00 and 01 are 249 I believe, havent weighed mine yet.

Oh yeah, 2yrs no problems or failures on the 98. So far only a cracked gas tank on the 00.

[This message has been edited by F-Pilot (edited 03-17-2001).]

MY 99' IS FLAWLESS............KNOCK ON WOOD!

G4

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NOPE..........BOY.......

That's not thunder ridin' your BUTT .........

It's a whole Damn HURRICANE!!!!!!

Have not actually weighed mine but the service manual indicates spec on the bike is 252lbs wet - thats with a full tank of gas..

Course thats just what Yama says..

I have a 98 and the only problem I have had was a bad valve and some fine tuning carb probs.. I did have a major problem with a dealer mech who replaced the crank, piston, cam chain and connecting rod instead of the bad valve... I think all it needed was a valve job and I got screwed.. They did all the other work and it still knocked and a week later a valve bent.. I had to pay for that one too but when that was fixed my baby was quiet and ran like a new one... oh well I am not bitter (yea right) :) ...

The only real problem I have is that its a monster and wants to run like a bat outa hell... I am lifting weights just to build strength to hang on... LOVE THE THING

well, i've had a '98, a '99, and a 2000. regarding the '98 cranks, i have heard the same thing, but mine was fine when i checked at 180 hours. that's 180 hours of cross country racing, a little motocross, some trail riding, and a few enduros. not to brag, but to qualify those hours, i ride the 4-stroke expert class off road. also, the gents at thumper racing (russ is a guru!) have told me about motors with 2-300 hours that never had the kind of maintenance i did that were just fine. i put in my 3rd piston at 180 hours.

water pumps: initially i had problems keeping seals in my '98. i changed the shaft to the '99 with the harder coating and had no further difficulties. i kind of think the seal may have been in backwards from the factory, because i went through several before i decided to try turning one around (the spring side is the pressure side) and that stopped the leaking completely. ok, ok, maybe i put the first replacement in backwards...

hope this helps. i personally have found these machines to be bulletproof. if i were looking for a good value in a bike and i had some money for fix up, a '98 yz400 would be very high on my list.

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will pattison

racer, engineer

www.ignitioninc.com

My friend has owned his 98 yz400 since it was new. He has had to replace a broken kick starter and had the water pump seal go out like mentioned above. I bought a 99 yz400 just because it came with the Excel Rims. I have not had any problems other then replacing general wear and tear stuff. (tires, chain/sprockets, chain slider) I did manage to put flat spots in the front and rear rims though so don't make the Excel rims your only reason for buying a 99 like I did. It might not be worth it but now I do have an excuse to get the black rims I've always wanted if I ever have the spare cash laying around.

Khris

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When in doubt, GAS IT!

THANKS FOR ALL THE HELP AGAIN. :) YOU HAVE REALLY HELPED OUT ON MY DECISION. THIS SITE IS GREAT :D AND WHEN I ACTUALLY GET MY YZ400 I CAN HAVE SOME INFO FOR OTHERS. THANKS FOR THE HELP :D

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