2001 Yamaha YZ426F project

Yes, there is, and it's usually a PITA to unscrew it, too.  You're going to need a 1" six point deep socket, a long socket handle, and some help to hold the frame down.  

The tools and help won't be a problem. Are the threads standard or reverse? Thanks for the heads up!

The tools and help won't be a problem. Are the threads standard or reverse? Thanks for the heads up!

Standard. He is right, it sucks. I thread taped mine.

Right hand threads.  They're just really tight is all. 

This is a great thread. I have been monitoring your progress. I have an 02 426 and plan to do just as you have. Are you going to use your stock cam? I am trying to find out info about a mod that will provide easier start and changes comp release set up.

I put in a little bit of work on the bike today. I installed the stator and flywheel into the new WR case. I set up my new clutch set up but forgot to order a new lock washer for the clutch nut, oops! While I'm waiting on that small but important part I decided to tackle removing the infamous oil strainer. I found a 15/16" was a perfect fit. I went with an 18", 1/2" breaker bar to start with. My plan B was to break out the 3 footer if things got real crazy. Unfortunately nobody else was around so it was just me and the strainer... I braced the frame my left hand to keep the bike steady. I was prepared to say a long list of profanities to enhance strength (seems to have worked in the past) but the strainer gave without a fight! Victory is mine! I cleaned it off and threw it back on.

@Billium,

Thanks, I'm glad you're enjoying the thread. It's been fun so far! I'll be waiting to check yours out when you get going on it. I actually already have the Hotcams cam so starting should be pretty easy going.

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I finished putting the motor together today. The timing marks are all lined up the way they should and everything is torqued to spec. I'm going to try to get the motor returned to its home in the frame tomorrow. Everything went together pretty smoothly. These Yamahas are pretty simple.

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Well i just came across this forum and im in the exact same boat. 98yota.. Who did you buy those valves from? 

thanks 

I mounted the motor back on the frame today. This thing is starting to look like a complete bike again!

@ 1bent02rapter, I ordered the valves and springs off of eBay. They were really reasonable.

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I made some more progress on the bike today. I installed the rest of the cooling system (minus the nice blue silicon hose on account the ones I ordered were the wrong parts). I still need to figure out the best routing for the over flow hose running to the new over flow tank. Everything else is pretty much buttoned up. I am going to tear into the carb this weekend. I am waiting on exhaust gaskets to mount the pipe. I installed some new billet levers and they feel great! They are really smooth and look nice too! Hopefully in the next week I can finally fire this thing!

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i found a good used head 

 

Edited by 1bent02raptor

I put in some work on the bike this weekend. I replaced all of the coolant lines and overflow lines with some nice blue hoses. I rebuilt the carburetor and threw it back on. I filled the oil and coolant and slowly cranked the kick start with the top oil line loosened. I turned the engine until oil flowed out of the fitting. I tightened the oil line and turn the motor some to make sure there was oil flowing throughout the motor. I turned on the fuel and prepared for a nice leg workout. The motor fired after a few kicks. It actually caught me by surprise! I kicked it again and the motor came to life and held a nice smooth idle. I let it warm up and twisted the throttle a couple times. These things have great snappy throttle responce! I didn't go crazy of course considering it is a brand new motor. I checked for leaks and then took it down the street a few times. The clutch is smooth and engages perfectly. Even as I babied it up and down the street I can tell this thing has some serious power!

After getting the bike back in the garage I replaced all of the plastics. The front fender is styled after a newer 450 bike. I'm very happy with how this project is coming along. I am waiting on some new grips and a bar pad. I also ordered a set of aluminum radiator guards. I posted some pictures of my progress. I'm not quite finished but I've definitely made some progress!

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I didn't want to over do it with blue so I opted to throw on a set of gold aluminum timing plugs. I'm happy with it how looks.

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I threw on a new bar pad and grips today. I went with black diamond pattern Renthal grips and a black and silver Renthal bar pad. It looks a lot better now. The ones that were on there were pretty hammered. I'm going to be installing a set of radiator guards tomorrow.

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I installed the radiator guards today. I'm happy with how they look and they are rock solid!

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I took the bike out for it's break in ride and it ran perfectly! Even though I was babying it during the break in process this thing still really wanted to take off! After I finished the ride I changed the oil and oil filter and everything looked great! Hope everyone has a great weekend!

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I took the bike out for an all day ride today. It ran perfectly! It was not popping at all. The motor did not get hot even in slow areas. The throttle responce was perfect throughout the day. The power is smooth and constant. This thing seems to have endless torque through the RPMs. I really like the WR gears as the first gear makes it perfect for negotiating tight slow obstacles. The wider ratio makes cruising on the long straights less dramatic as the rpms are lower. The clutch operates smoothly which I wasn't expecting for a brand new unit. I did not stall the motor one time. I might not even change to the WR flywheel and stator setup as the motor is already manageable. More good news is every time I turned the motor off for a break, it would start right up with a single kick. So far, I absolutely love this bike!

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That's awesome, strong work!!! Those pics make the perfect backdrop for your bike.  :thumbsup:  :thumbsup:

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