Project 90 YZ Finished!

Photos by LeBig

I’ve always enjoyed tinkering out in the garage on some project bikes from my youth. I’ve built up a 90 KX 250
an 89 CR125 an 88 YZ250 and maybe my personal favorite, my old 90 CR500 from back in the day! I’m very fortunate that I have a lot of hook ups for parts and things but really, most of this stuff I have to pay for but at a deal. I’ve sold the KX and the ’88 YZ as well but holding onto the other two for, well, I’m not sure. My wife did let me bring that 500 inside the house so there is that.

I wasn’t looking for a new project bike but when my FRIEND Jamie AKA Darkside told me he has an old ’90 YZ125 in his shop that he needed to get rid of because he needed money for this shop he was building, well I figured I would help him out. Jamie dropped it off before Anaheim 1 this year and he did warn me it was in pieces but I guess I wasn’t quite ready for what he gave me. Which was rusted pile of bolts and a bike that was hammered. This bike was a lot of work and more money than I wanted to put into it as well. Also, because I didn’t take it apart and was just handed zip lock bags of bolts, I had to figure everything out as I went along.

I blame Mr Side for my frustration but in the end, things came together pretty well. The ’90 YZ wasn’t anything special, it wasn’t a very great bike. Just kind of average, it had the anodized red forks which were hella-ugly and caused me some issues as you’ll read below.

The costs for this bike are as follows but keep in mind, I didn’t pay for everything listed below but it should give you an idea of what something like this costs.

Bike- $1000
Dubya DID rims/wheel rebuilt/stock hubs were used $750
Micar machine shop fab work $250
Race Tech Rebuild fork and shock $1500
Suspension Direct Kashima coating $1000
GUTS Seat foam $65
UNI Filter $40
Doc Wobs fuel tank $400
Wiseco Piston Kit $140
Wiseco Bearing kit $40
Pro-X Con Rod Kit $100
KE3 Vapor Blasting $400
eBay for used parts/NOS etc $1826.
Motosport.com for OEM Parts/UFO Plastic $5850
Renthal bars/sprockets/chain $250
Powder coating frame/tank $400
DeCal Works stick kit $100
Sudco Mikuni PWK carb $300
V Force Reed Block $150

**Here she is! I like the look of the Yamaha’s around this era. Yes, I know Damon Bradshaw was #45 in ’89 and not ’90 but it’s the same bike and so sue me.**

**Ok, I’m not a fan of the black rims but that’s what Dark had done before I got the bike.**

**I did put a modern YZ clutch perch on this bike. Those old ones sucked.**

So the pipe came with a nickel plated FMF and I couldn’t find a “normal” one for it anywhere. Payton wouldn’t make me a one-off pipe either no matter how hard I begged. So I saw Coty Schock took a plated pipe and with heat and a wire wheel got it looking great again. So I shipped mine to him and he did a great job of it. Thanks Coty!

As anyone knows, old YZ tanks get yellow and disgusting after a while. So my buddy in UK Doc Wobs got me an aluminum 250 tank that bolted on, it’s a tad bigger than 125 one but works fine. I got it powder coated white.

This might be the coolest part on here. I found a still in the package YZR front brake hose guard on eBay! I mean, kind of neat right? Also, that’s a ’95 RM front caliper as they’re all the same for Kawi, YZ and RM around this era.

**Renthal dialed me in with sprockets, chain and bars. Dubya USA did the wheels**

**DeCal Works did the kit up for me, I mimicked the factory bikes of this era with the Acerbis on fork guards, Yamaha name on front fender.**

Couldn’t find a good ignition cover so that one is from eBay, best I could do. The chain guard and radiator louvers were from France, they were 3D printed copies of the OEM plastic. Thanks to Sudco for the PWK carb and Tassanari for the V Force reed block also.

**Cloth bar pad naturally, the Kashima coating on forks from SDI looks great.**

I struggled with the brake pedal, the OEM return spring- still not totally happy with the pedal but they’re not available to buy. I found a nickle plated bolt kit for this bike on eBay and they look pretty good!

Sandberm says:

September 26, 2023 at 8:30 pm

Gonna need a lengthy ride video Steve. This tiny writeup will not suffice.

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Mike Grzych says:

September 27, 2023 at 10:27 am

Vapor blasting is a game changer. I restored a few 81 Suzuki RM125x and getting parts or becoming a huge problem. Did you struggle to find parts or was it just a lot of time on the computer searching? Nice job. I don’t know if I could ride it and get it dirty after all the work put into it!

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Jimbo128 says:

September 28, 2023 at 11:34 am

Any before rebuild pictures?

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Nacho Fortado says:

October 7, 2023 at 6:16 pm

Black rims are a miss – IMO. Good job tho!

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