Well things didn't seem to be working to my satisfaction and I had to do some changes. I had to relocate the lower rear shock mount, the previous position reduced the trail to much in the front end, making the bike feel like you were on a pocketbike. Then there was the cooling system refusing to bleed all the air out properly. *(hasty designing will lead to flaws showing up later as the project comes to a close)
5 days before we set out for the maiden track test, we reworked the entire cooling system, changing out the rear radiator for a different unit and re-routed all the hoses. Time for a shakedown run after work hopefully.













The last trackday was a cooler day, in the low 50's. Jetting was spot on and the bike was running great. The only problem that I ran into all day was with the front suspension. I have since re-worked it and made a new right side fork spring spacer. The big brake master cylinder works like a charm, and is very predictable. I can't wait to get it back out to the track for some further testing and modifications.

Current Bike / Modifications
1987 YSR50 chassis
'01 YZ125 water-cooled Engine with Mikuni TMX38 Carburetor
'01 YZ125 Throttle Assembly & cable (cable shortened 4")
NGK BR9EIX spark plug
Boyesen Rad Valve Intake System
Boyesen Hi-Flow Water Pump Cover & Impeller
'80-'83 BMW 320i air intake boot with UNI filter (from Honda TRX) *I machined an aluminum adapter to go from the boot to the filter
428 chain & conversion sprockets 40,41T rear aluminum / 16,17,19T front steel
'96 TZ125 Expansion Chamber/Silencer exhaust system ** (YZ coupler welded onto headpipe of exhaust)
TCR Aluminum Fork Brace
TCR Aluminum Top Triple Clamp
'01 YZ125 split perch & clutch cable/lever (cable shortened 4")
Nissin 5/8" Bore Front Brake Master Cylinder (Suzuki Katana brake lever - shortened 1") with aluminum banjo bolt
Steel-Braided Front Brake Line
Aluminum Wheel & Swingarm Spacers
Electrical shift assist - Kwikerr Clicker
Aluminum Rear Brake Stay/Brace with modified (lengthened) rear brake lever actuation arm
Footpegs moved up and back 1-1/2" x 1-1/2" with Aluminum setbacks
4-1/2" longer swingarm (a modified stock arm using Chrome-Moly Steel)
TCR Swingarm Bushings *silicone-bronze
relocated lower rear shock mount
relocated & braced upper rear shock mount
frame side sections are boxed in with 1/8" thick steel plate, side holes are capped, new bracing to remove side-to-side flex
 Fuel Tank Petcock for 7mm hose (Yamaha # 2K5-24500-00)
Fox Shock with remote compression adjuster
Dual Fork Springs with Aluminum Spacer and 30wt fork oil
Daytona Steering Stabilizer/Damper
Aluminum windscreen brace
Tapered Steering Head Bearings
71*C Thermostat (German unit) with Machined Billet Aluminum Thermostat Housing (By-Pass Style)
Front Radiator (VW heater core #171 820 041A)
Rear Radiator ('86 CR80 Radiator)
 1982 Yamaha Vision XZ550 expansion tank
Fabricated Chrome-Moly Steel Engine Mounts with Urethane Rubber bushings (front, middle, and rear positions)
Stainless Steel / Titanium / Aluminum / Chrome-Moly Steel nuts, bolts & washers

Coolant hoses are supplied from various automotive applications




Coming Additions
Aluminum Swingarm (4" longer than stock)
Aluminum Rims (12"x2.5" front, 12"x2.75" rear)
Aluminum Adjustable Rearsets with shifting linkage
Complete Bodywork Set (upper, lower, tail, windscreen, front & rear fenders)
TrailTech Motorcycle Computer
clutch steel plates, friction plates, & springs
**Hinson Billet Pressure Plate(*acquired) & Clutch Basket(*acquired)




I use Maxima Castor 927 pre-mix oil (16:1 ratio)
Phillips TT105 racing fuel (oxygenated)
Distilled water with Redline "Water Wetter"
Castrol GTX 10w40 oil
PJ1 fork oil 30wt
Maxima "Chain Wax"
ATE SuperBlue Brake Fluid
Lubro-Moly (*Liqui-Moly) Hi-Tack spray

----------------

The following people & businesses were involved in some way, shape, or form to help out with these projects:

My wife and family, Callie, Peyton, and Ryan

Monty Shepard

Marc Bradley

Tommy Gee

The folks at Maxey's Motorsports - Ray Jones, Chris Marlowe, Brad Brown, Chris Swanda, Chris Griffin, Danny Carlisle, Phil Gordon, Phil Eby, and Corly Jones

Team Calamari Racing

Kerr Automotive Imports, Inc.

Ebay Auction Site

Eric Gorr at Forward Motion Racing

All the folks at the Dirt Rider.net forums

All the folks at Tony Tice's YSR forum

All the folks at the YSR50 forum

The Stephens Family from Hallett Racing Facilities


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