WR500 advice

I thought the 92 was already in a 250 chassis, so the handling was improved over earlier models.

Suspension can always be improved with modern valving and appropriate springs.

The detonation and erratic jetting can be improved by having the squish in the head modified. As a C rider, the 490 had more than enough power for me.

Vibration can be reduced a little by balancing the crank, and different bars/ grips.

Buy the bike, you won't be disappointed.

Super cool bikes. Would be great on a sand track. Supercross not so much.

https://motocrossactionmag.com/1992-yamaha-wr500-how-the-air-hammer-bec…

The motors were really crudely assembled, if you clean up the porting and get the head dialed it's a whole new bike.  It won't quite hang with a CR or KX 500 but shouldn't be that far behind.  That said a more modern 250 two stroke will handle better, be easier to ride and make about the same power (2000+ CR250R, 2005+ YZ, 2003+ KX).

I have two that I would like to sell - located in San Jose…

I bought a bike from MxNick…. Straight shooter👍

I have no idea.  But I do know that if you build it up as a replica of the one Bradshaw rode at the 92 500 USGP you'll be the coolest guy at the track.

That was a good article.

Id like to see a WR fixed up as a modern YZ 490. 

I had a 92 WR500 years ago and was happy to sell it.  It vibrated far too much.  Arm pump and numb hands!  

Just getting the head cut and jetting it decently will make a big difference. It’d take a pretty good effort to get one running with a KX500 / CR500 though. You’re dealing with mid 1970s technology vs late 1980s tech, and there was a lot of improvement in those years. 

That was a good article to get the day at work started.  Thanks for posting.

100% the head mod is the first mod required, and the biggest single change you’ll make.

I raced a Wr500 in 2015-2016 at the Vintage races

I loved the bike

I had the head mod done,Pro Circuit pipe and silencer,boysesn reeds

Kx 500 keihin carb,had the suspension done

Great bike,handled ok,worst part was the brakes

The front disc is like a 230mm,,doesnt work on a 250lb bike very good

I was always going to upgrade to a 1992-1993 Yz 250 front fork,then you can get a bigger front brake,and also a 1992 Yz 250 swingarm saves weight and lets the bike turn better

I wish I had never sold mine,would love to find another one

A guy in Georgia stuff a WR500 engine in a modern aluminum frame YZ chassis.  This was back in the early 00's.

Head mod, cylinder clean-up, PWK and pipe, your blowing by your buddies if you the rider to do it. It will make as much if not more than any stock 250.

Give Klemm Racing a call. They make the motor quite usable and reliable.

http://www.klemmvintage.com/

That would be totally cool 👍

I’m gonna keep my eye out. I wouldn’t mind  riding one of these. Seems like Kaplan Cycles had one these not too long ago. Of course it was probably over 15K after they cleaned it up.

Here's such a thing - may be the bike you are writing about , but I think I can see the steering wheel on the Ute on the correct, Right  hand side, so probably an OZ - Kiwi build:

 I have difficulty now posting more than one image  - here's the other side .

When I went looking for this, I re-discovered  in my picture folders a YZF Chassis with a 490 engine with a Watercooled top end, Quite the project. 

Guy's bike I saw had a WR500 engine tucked into a YZ250 (two stroke) aluminum frame. Other than the air cooling it looked straight from factory.

OP, not sure it’ll ever be a CR/KX. But it’ll be fun if you appreciate it for what it is  

Only thing I’ve read is to get the done reshaped before anything else. In the past year I’ve done 2 KX500s and a CR500, have been on the lookout for a WR but they’re near impossible to find.