Light fuel leak in action? GSX-R750 GR71 Carburetor maintenance (OH)

It still doesn’t feel like logistics and everything are back to normal operations.
Parts and materials aren’t arriving at all.

We’re moving forward with work using parts as they gradually arrive.

The “TM29/14” acceleration pump plug works with GSX-R750 carburetors.

The acceleration pump plug from Mikuni’s classic TM(RS) carburetors is a compatible part.
Since we don’t know when this part will stop being supplied, I stocked up a bit.

That said, since one bike uses four of them, I only have stock for three more bikes.
If you contact Mikuni’s distributor JBS, they usually have it in stock.
They also carry some rather obscure Mikuni genuine parts,
so if you’re stuck, it’s worth reaching out to them.

You insert the plug by threading it through the acceleration pump nozzle.
We also replaced the O-ring on the acceleration pump nozzle, so any seepage around it should disappear.

We also found a newer generic-style float valve?
and swapped it in.
Of course it’s the newer rubber type, and the fuel level is spot-on.
Still testing it, so it’s hush-hush. *But it’s fine…

The actual fuel level height and the speed at which gasoline flows in should be perfect.
The acceleration pump nozzle is
adjusted to spray right in the center of the butterfly.

NGK DR9EA “successor is JR9B” tip-cut and improved vibration resistance model

Before starting the engine, let’s check the spark plug just to be sure.
The original-equivalent DR9EA is installed.
As a compatible successor plug, there’s the JR8B, which is also used on oil-cooled 1200s.
The tip’s both corners are cut, reducing the weight of the tip.
This reduces electrode resonance from engine vibration and improves durability against electrode breakage.

The newer the model, the more improvements you often find.
Comparing old and new is interesting.

The tip is cut like this.
I replace all DR-series plugs with JR.

*GPZ900R and GSX1100S are also DR-series.

Engine start! Carburetor synchronization

No gasoline leaks and the engine starts perfectly,
puffing away! Now we can relax.

The original complaint was occasional overflow,
but the inside of the carburetor was in far worse shape than that—we were shocked.
The condition of the fuel tank was also quite poor; it’s amazing it was running at all.

We’re currently doing rust removal on the fuel tank,
so we’ll decide what to do based on tomorrow’s condition.