I couldn’t help myself, I had to know why Scooty wasn’t running.
So yesterday I left off with a scooter that barely ran, if it even started, apart from the odd time it ran like a champ and then just ran out of life.
I figured it was fuel related, as blocking the intake was enough to richen the mixture into a state where it ran a little better. My first point of action was to remove the carb and see what was going on.
Removing the carburetor is a bit of a faff with little access, but thankfully its really just a straight forward game of removing things around it to gain access.
THe throttle cable needs to come off the carb too. This is done by removing the black cover on the LH side of the carb, and slipping the cable out of the holder. The end piece of the cable isnt solidly attached, so take care not to lose it.
The carb is then held on with an 8MM bolt on each side. I found a combo of a small spanner and long screwdriver on the LH side worked best, and a 1/4″ 8MM socket and short extension on the RH side. Once they are off, the carb is freeeeeeeee.
Into the garage we went, for a checkup. The first job was to clean down the outside of the carb as it was very dirty. With it a bit cleaner I removed the float bowl, taking care not to damage the seal.
I removed the main jet (the big round bronze thing with a slot in it in the above photos), and gave it a quick clean. The hole was clear of obstruction and it didn’t look dirty. I blasted brake clean through all the passages in the carb, making sure they all flowed freely. I then removed the pilot jet. This is recessed in the tower in the middle of the carb next to the main jet. It was a bit sticky to remove, and when it was out it was covered in grime.
I noticed I couldn’t blast any carb cleaner through the jet, either way. It just wasn’t getting through the head of it. Sure enough when I pushed some stiff wire through the jet out came a nice clump of hardened goop. You can just see it on the tip of the wire
The pilot jet was well and truly blocked. With that cleared I could blast cleaner through both ways. That blockage would not help the running of Scooty. I suspect this was down to years of use, and then sitting around for the past 6 months unused, just causing a buildup. Hopefully my occasional use of fuel system cleaner in the future will reduce this risk.
Refitting is the reversal of removal.
With it all back together and on the Scoot, a test fire was in order. It took a few cranks on the electric start to fill the carb with fuel again, but once it did, it started and ran like a champ. It idles well, revs out well and doesn’t cut out. Great success.
I then donned my sweet new helmet (A Zeus 613C modular helmet. Open face when I feel the need for wind in my beard, or full face when I want to be mad knee-down superbike racer), and went for a hoon down the road. It runs and rides pretty well, although its feels strangled at higher throttle positions. Hopefully this is just a restriction in the exhaust as per the plate on the frame (the restrictor is one of those urban myths, so it will be interesting to confirm if it has one or not).
It still smokes like buggery, but hey, it’s a 2 stroke, its part of it. Once it works through the incorrect oil it might smoke less, too.
Connecting this helped a bit. The indicator light on the dash works, and I have seen the oil light flicker when the ignition was turned on, so something must be happening now. The fuel gauge is an unknown for now, as I havent got enough petrol spare to fill the tank and see if it goes up or not.
I did note that the main headlight bulb isn’t working, only the secondary bulb seems to work, so I’ll need to fix that too. The bulb looks ok, so I’ll need to get the multimeter out.
I had to disconnect the brake light switch for that lever as it seems to be stuck on. Not ideal.
I removed the mirror stumps and measured them, so I’ll go hunting for some cheap mirrors with an 8MM thread. I hear it’s useful seeing behind you when riding.
I have a replacement set of switches on the way, and a replacement brake lever. Its progress, and not too expensive either.
It was great fun hooning around. Its been so long since I was last on two wheels I really forgot what its like.