Stink Racing

The background:
I had a Bucket. T'was an '89 ZXR250A with a GL145 engine. Sadly I blew the engine (dropped a valve actually) and incurred the wrath of the previous owner/builder - a certain Bis'tard.

I attempted to make amends by putting a CB125T motor in it, but it seemed to have rejection issues as the motor never ran quite as it should have. The motor went up for sale and was quickly sold. The new owner swapped the ignition and carbs and the motor runs fine

Oh well. What to do with a perfectly good chassis? Hmmm, I have an RD400C in (just under) one million parts - all in one box. Sitting round drinking and a plan is formed. Like all plans that are conceived while drinking it was brilliant! Fit the RD400 engine into the ZXR. Simple!

Yeah, right.
Follow this blog and you'll find out.

Oh, if you have any knowledge of these engines I'd be keen to hear from you!

Anyway, I'll give you an overview of the plan. Basically a standard ZXR250A frame, wheels, steering and suspension. Yes, even the 18" rear.

The engine starts as a stock RD400C to which we plan to do the following:

• 90° firing
• clean transfers
• chamfer the crank to clear the transfers
• raise transfers 1.5mm
• enlarge exhaust to 67% and 6mm higher
• open out piston ports
• flatslide 28mm carbs
• TZ-type bearings each end of the crank
• electronic ignition (currently points)
• chambers
• lighter flywheel

I'm hoping for between 50-60hp at the rear wheel. 50 is the target; 60 is the dream.