Project Veronica Part 2: Carburetor & Fuelling

Hey guys, Matt here with an update on Project Veronica. Last time I talked about bringing the 'Yammy in for a close look at the 30+year old carburetors and sorting out some misfire issues. This week, I'd like to talk about what OEM and aftermarket options are available for us XS750 owners.

Kicking the bike over, she started fairly easily with a few kicks however there were a few very apparent issues that needed addressing, namely:

  • Really high idle (~3000rpm)
  • Missfiring
  • Backrifing
  • Poor throttle response
  • Poor choke performance

 A quick look in the tank and there was some fuel but I decided to fill the tank with some fresh 95RON fuel. This made a minor difference, meaning there was either a real issue with the timing of the engine, or there were serious issues with the carbs themselves. Being a 30+ year old bike still running the original carbs, it was a safe bet that the insides of the carbs were rotted and gunked up.

So I dropped the bike off to Ron @ Flywheels Motorcycle Engineering and he confirmed that the carbs were junk. At this stage the rest of the bike was in real good shape, so I had a couple of options:

  • Source a rebuild kit and refurb the entire carbs
  • Purchase a set of replacement carbs
  • Source a set of Triumph triple carbs which apparently bolt-on

After some thought, I think the safest bet at this stage is to purchase a set of new carbs. Fortunately, after chatting with Tom at MikuniOZ I discovered that they sell a complete bolt-on upgrade kit that really wakes up the 750 engine, plus giving smoother throttle response, better fuelling and being a new unit...I don't have to worry about non-rebuildable parts like shafts etc giving me issues later on.

Completing the intake side will be a new set of OEM carb holders that I sourced from Mike's XS and new 55mm pod filters. 

I couldn't find much info on the 'net being a relatively new kit on the market so I'll be documenting the install process, performance and overall thoughts on the kit and the whole tuning experience. 

 Stay tuned!


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