99 Wr 400 rebuild opinions appreciated.

Hi, I have a 1999 Wr 400 that is currently being rebuilt to the YZF-426 components. I've used the parts list from the forum and powroll. I'm

still not sure on which crank assy to use. Would it be for the wr 400 or 426?

Parts numbers are 5GS-11400-00-00 which is the wr400 or the

426 5JG-11400-20-00.

Also I'm debating on doing both Hot Cams while it is in the shop. I'm sure everyone will say go for it.

I plan on using it as a commuter bike and am looking into some street tires, alittle more street then the Dunlop D606. Also need a new chain and sprockets so I'm looking for recommendations for the sprockets to make it more street worthy.

Any help would be appreciated as this is my first dirt bike and I'm not very mechanical yet.

I used the crank assembly from the 426, which is what you'll need if you're using the 426 piston as well...if you go that route, you'll also need to change out that keyed gear for a splined gear...

I did Hot Cams as well...don't know what my sprockets are off-hand, and I'm using Avon Gripsters for street rubber, that are great....

Hey, glad to see you are still on here, I had messaged you last year about my rebuild. Finally getting to it. heh. Thanks for reminding me about the gear, I had forgot.

Need the balacer gear as well. If by 426 components, you mean the piston and barrel, you will need the 426 crank.

Ok thanks, I don't think that was on the list either.

The dealer I took it too doesn't have a clue as what parts are needed to do this. The parts guy told ME to look them up and give him parts numbers. My dad works at a shop in Florida so I'm having him ordering parts for a discount.

Need the balacer gear as well. If by 426 components, you mean the piston and barrel, you will need the 426 crank.

You can get the stock crank rebuilt with a 426 rod (as my two 400s have) in which case you wouldn't have to worry about the balancer gear. However, if I were to do it again, I would upgrade to the 426 crank.

Hey, glad to see you are still on here, I had messaged you last year about my rebuild. Finally getting to it. heh. Thanks for reminding me about the gear, I had forgot.

haha...yea, no rush, right! It's been a long time at this point, but now that it's been mentioned, you may want to look into the balancer gear as well, that sounds familiar...

Here's an excerpt from one of my earlier posts...may want to do the research on the Luke's kit while you're at it:

Yup, had to replace the primary drive gear because I used the 426 crankshaft, which requires a splined gear instead of the woodruff key...a positive thing in my opinion, after seeing all of the sheared woodruff key issues...I'm pretty sure these were the only 426 parts I needed:

5JG-11400-20-00 WR426 Crank Assembly

5JG-11536-00-00 WR426 Drive Gear

5NG-11631-10-00 WR426 Piston

5JG-11633-00-00 WR426 Piston Pin

5JG-11603-00-00 WR426 Piston Ring Set

93420-19084-00 WR426 Piston Pin Circlips

5JG-11311-00-00 WR426 Cylinder

I honestly can't compare the power very well, because I don't think it was running up to it's potential before hand. I bought it with a knock in the bottom end, and only got a few rides on it before it seized...but It definitely seemed to have a lot more top end when I was done with it...

I did the conversion mostly for the reliability (426 bottom end w/400 top end is supposed to be most reliable)...

You may want to look into sending in your original cylinder to Luke's to be re-sleeved, and get their 444 kit, which should be compatible with the 426 crank, for probably less than it costs to get a whole new 426 piston and cylinder...

Good luck!

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