1999 YZ400F Shit hit the fan

[1999400F]

Well I sent the bike off to be looked at by my Mechanic and he is telling me the head is completely wasted and needs to be sent in to be machined and then rebuilt-around 600 dollars. then the cylinder needs to be re-sleeved and nickle plated-around 250 dollars. It also needs a few misc. parts on it, some washers here and there and an ignition coil. All in all it comes to an 1100 dollar bill. I paid 1000 for the bike. My question is, what is a good roller going for these days? The bike has a freshly powder coated frame nice tires and gold excel rims. Forks don't leak and rear suspension is good. Also can I sawp in any other motors? a 426 or 450? thanks!

[hoss400]

I think any 400/426 up to 2002 will bolt in

Sorry to hear about the kaboom :sad:

[grayracer513]

So if the head has damaged cam saddles and needs a valve job, then I can see 250 for the cam bores, $100 for valves and springs, plus $150 for a valve job, totaling $500. The cylinder's not priced badly, but you could look into a big bore kit.

Swapping engines is possible by using a YZ or WR 426 or 450 up to '05, but you may need to machine some custom collars to accept the swing arm pivot correctly iif the engine is later than '01.

The cheapest way out may be to buy another 400 or 426 and part out what's left after you take the best stuff. A 400 roller can't be worth much more than the wheels are, really.

[hoss400]

So if the head has damaged cam saddles and needs a valve job, then I can see 250 for the cam bores, $100 for valves and springs, plus $150 for a valve job, totaling $500. The cylinder's not priced badly, but you could look into a big bore kit.

Swapping engines is possible by using a YZ or WR 426 or 450 up to '05, but you may need to machine some custom collars to accept the swing arm pivot correctly iif the engine is later than '01.

Good ol greyracer, This man knows his stuff

[1999400F]

So if the head has damaged cam saddles and needs a valve job, then I can see 250 for the cam bores, $100 for valves and springs, plus $150 for a valve job, totaling $500. The cylinder's not priced badly, but you could look into a big bore kit.

Swapping engines is possible by using a YZ or WR 426 or 450 up to '05, but you may need to machine some custom collars to accept the swing arm pivot correctly iif the engine is later than '01.

The cheapest way out may be to buy another 400 or 426 and part out what's left after you take the best stuff. A 400 roller can't be worth much more than the wheels are, really.

I'll keep my eyes peeled for an engine...Also can I put a 426 or 450 cylinder and head on it and be good?...obviously replace the piston and everything to fit the new cylinder.

[grayracer513]

A 426 head will fit.

An entire 426 top end can be used, making it a 426, IF you use a 426 crank, or have yours rebuilt with a 426 connecting rod so as to match the larger wrist pin of the 426 piston.

A 450 head will not bolt on to either a 400 or 426 cylinder.

There are some who say that a Gen1 YZ/WR450 top can be used on a 400/426 with the above crank mod, but I tend to doubt that it sets up correctly, have no solid info on the matter from a source I consider reliable, and I don't recommend spending any money on such an attempt unless you have some to risk.

[1999400F]

A 426 head will fit.

An entire 426 top end can be used, making it a 426, IF you use a 426 crank, or have yours rebuilt with a 426 connecting rod so as to match the larger wrist pin of the 426 piston.

A 450 head will not bolt on to either a 400 or 426 cylinder.

There are some who say that a Gen1 YZ/WR450 top can be used on a 400/426 with the above crank mod, but I tend to doubt that it sets up correctly, have no solid info on the matter from a source I consider reliable, and I don't recommend spending any money on such an attempt unless you have some to risk.

Ya I think I'll look for an engine or a good condition cylinder and head

[Stinger1133]

For the price of an engine on ebay I would just let the dealer do it. Plus you get a warranty if they do the work right ? Total invested in the bike will be $2000. Still not to bad and you know the engine will be in great shape afterwards. If you buy another engine for it, it could have some issues also that could possibly turn into a money pit after you get it. Just my $.02.

[hoss400]

I think I saw a 426 motor on here in the classifieds for $900 complete. Don't hold me to it but take a look. Good Luck

[crf450319]

I looked on Clevland CL and found a few bikes for around $2100 - $2700, '05 to '07 yz450f's. If I were you (and had the $$) I'd part out the 426, used engine cases for that bike sell for $200 - $300 and the rims should sell for around $300 as well. You should almost be able to recoup your initial $1000 after you've spent some time taking it apart and listing stuff. Then I'd go buy an '06 or newer yz450f, if you can swing it...

[1999400F]

I looked on Clevland CL and found a few bikes for around $2100 - $2700, '05 to '07 yz450f's. If I were you (and had the $$) I'd part out the 426, used engine cases for that bike sell for $200 - $300 and the rims should sell for around $300 as well. You should almost be able to recoup your initial $1000 after you've spent some time taking it apart and listing stuff. Then I'd go buy an '06 or newer yz450f, if you can swing it...

It's definitely a good suggestion but I don't have the money for an 05 and I found a kid on Craigslist about an hour away from me with a 426 engine still in bike so i can test ride it for 600, he also has a brand new yamaha 400 cylinder and low hour head for $600 or a bored out 400 cylinder for $400 with head the low hour head. Trying to exercise those options to get it running again then maybe list for $1500 or keep.

[1999400F]

Also does anyone know if my hot cams out of my 400 will fir the 426 engine?

[grayracer513]

Yes, they will.

[crf450319]

It's definitely a good suggestion but I don't have the money for an 05 and I found a kid on Craigslist about an hour away from me with a 426 engine still in bike so i can test ride it for 600, he also has a brand new yamaha 400 cylinder and low hour head for $600 or a bored out 400 cylinder for $400 with head the low hour head. Trying to exercise those options to get it running again then maybe list for $1500 or keep.

Well, sounds like you have some decent options then. When you'd been talking about repairing the original engine I was thinking it'd end up costing you way more than what it's worth. If you can get that thing running, or even put a different engine in it all together for $600 then I'd say you're doing alright. Good luck & keep us posted.

[1999400F]

Well, sounds like you have some decent options then. When you'd been talking about repairing the original engine I was thinking it'd end up costing you way more than what it's worth. If you can get that thing running, or even put a different engine in it all together for $600 then I'd say you're doing alright. Good luck & keep us posted.

No your totally right..I was quoted over 1k for the original head and cylinder to be brought back from the dead so my first though was part it out! Then I found this guy on CL with 400/426/450 parts coming out of his ears so I'm trying to strike a deal...The unfortunate thing is he is trying to liquidate so I can't trade my bottom end plus cash for the 426 engine :/. He's not pushing any of his stuff so I think I have a couple weeks to make a move.