Bring out your dead!

[breakdirt916]

why build it when you can prob. buy it for $1,200?

yamaha yz 490

[csmutty]

Hahaha you put it in your signature.

Oh man that was good. Well played Josh.

- - - Updated - - -

Hahaha you put it in your signature.

Oh man that was good. Well played Josh.

[Kurlon]

About - YAMAHA WR500

YZ490 motor in a YZ250 frame isn't all that crazy an idea, even Yamaha did it...

Someone took it to the next level and sumo'd it in 91...

YZ490 ‘Supermotard (1991) | Yamaha Community

Cylinder is on it's way to Millennium Tech to see if it can be salvaged. Still chasing my knock but I know it's not the crank now. I may update to the 98 waterpump setup, better flow and no slop in the drive assembly.

[Kurlon]

MT confirms, cylinder is only suitable for "recycling into beer cans."

[breakdirt916]

Wow that was quick...pretty sure my mechanic was playing me when he said it millennium lost the cylinder

Well it needs a split to find the knock anyways...

[Kurlon]

No split needed, knock is just normal straight cut primary gear lash, aka I'm hearing things. Bottom end is ready to go, just needs a top end which I no longer have... MT was damn quick, they called at 3pm after USPS tracking said the cylinder arrived at 1:40pm.

[csmutty]

Do they have a cylinder for that on the shelf or are you going to have to go used or oem?

[Kurlon]

Nothing in inventory, OEM hasn't been an option for years now, so if I rebuild it's going to be on a used core.

[csmutty]

Nothing in inventory, OEM hasn't been an option for years now, so if I rebuild it's going to be on a used core.

Are there any other cylinders from other bikes that share the same water jacket and cylinder stud hole patterns?

[Kurlon]

Not that I'm aware of, the closest is other YZ250s in the 1989 to 1998 range, but there are other differences that prevent them from being bolt ups. Exhaust flange and intake position differences require cut / weld and airbox redesign work to accommodate. If I'm going that far I would rather try and jam in a current gen YZ250 motor. If I'm going that far... why not just build a modern YZ250... and eventually that train of logic has me on a new YZ450F wondering where do I put the premix.

[csmutty]

I like everything except the 4 stroke...

[carsick]

Pffft, they don't even smoke when you feed them premix! That's efficiency for ya!

[breakdirt916]

assuming you saw this *cough* sleeved POS

1990 90 YZ250 YZ250WR WR250 YZ WR Cylinder Jug Barrel Sleeved Top End Engine | eBay

not an 88/89 (different rod) or 95+ (different exhaust mount/what?)...perfecto!

I say OEM cylinder bore n everything, then run it for the season then sell bike/sumo separately!

message seller offer ninny..counter @ huned

[Kurlon]

Yeah, there is a whole slug of damaged all to hell and badly sleeved cylinders on ebay. I missed a NOS 92 unit that went for $400 in January...

[breakdirt916]

Wow...look at this one...like sumo front fender...and it's a Wr


http://inlandempire.craigslist.org/mcy/5634537908.html

I called him about his front brake setup...I kinda wanna sumo setup but want to find a better front brake setup

[Kurlon]

EBC OS6028E Oversize Rotor Yz250 94-97wr250 92-97

Edit: Also, picked up a 92 and 94 cylinder, both need repair as they have damaged bores but they both should be revivable. Next task is finding salvagable power valves.

[breakdirt916]

can you fit errrthing in a '03 YZ125 chasis??

03 Yamaha YZ125 with extras

[Kurlon]

Could I? Sure... but... why?

I'd still need to figure out an engine, my forks are better than those forks... dunno what that option brings to the table?

[breakdirt916]

Newer chassis than the WR?

Also did not realize your forks were better

Didn't you want to put your 265 in the newest frame possible?

[Kurlon]

Other way around, I'd like to put a modern motor in my chassis as that's currently the pain point on repairing it. If I'm starting with a newer chassis I'll utilize the new style motor as well.

[breakdirt916]

K...will keep looking.. that'll be easier to ship anyways if I find it local

Edit - missed that you found some cylinders - what did millennium say about them?

That seems the easiest way - slap another 265 and you are back in biz

[Kurlon]

I haven't sent the new specimens to Millennium / Eric Gorr yet, no budget. Buy me! Both have damaged bores but should be revivable. I'm actually looking at having a different tuner work over the top end this time to try a different config out. Hopefully the final setup will help with the power spread and possibly find a bit more on top to boot.

[breakdirt916]

did you adjust the ignition timing on the previous mil for that top end boot?

[Kurlon]

Nope, in order to set timing you need a baseline, which on these machines requires knowing what PN CDI you have. This information is not helpfully stamped on the CDI. So I know my timing is advanced, but I can't tell you by how much. I also know that running VP C12 I had no detonation, and was able to confirm that during my post fail tear down. Backing the timing down a touch would likely give me more overrev, but again, I have no reference to go on as to where I am relative to stock. At some point I'm going to plunk down for an aftermarket ignition system, likely an HP programable setup and dial it in but that costs money... see previous post as to why the top end hasn't been redone yet.

[breakdirt916]

where dis at