Stink Racing

I have now got two matching E barrels. They have been bored to match the RZ350 pistons I have. Still working on port timings. I also have two cranks on the way - a C and an E.

Still gathering info from wherever I can. One tip I have been given is to use RD250E conrods. EDIT: this has now been suggested as a bad idea - a lot of work for no real gain. The longer stroke of the RD400 conrod is better for a few reasons whereas the RD250E is good for only one reason.

Well, having done the roughing out of the intake ports I find very different ports at the end. The engine actually has two quite different porting jobs already done on it.

Yep, a wally has been here before me. I thought the worst was the screwdriver that had been used to pry the cases apart; or maybe the piston that was in backwards (piston ports showing in the exhaust port). But no. They have actually put a barrel from another model with different porting onto the engine. ...

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This is the start of the engine rebuild. TZR reeds (6 petal vs the standard 4). There's not much metal there so I have to be careful not to go through the sides. The crank needs a full rebuild and I'll be replacing the bearings and seals in the gearbox.

Pic shows the standard (on right) vs the grind for the TZR (on left). The port window hasn't been done yet as the final timing and window width haven't been decided. A few more calculations and measurements to make yet.
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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
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