Motorcycle Diagnosis Fail

A few weeks ago, the Italica Bulldog 150 developed a weird and dismaying behavior: After several miles of riding at highway speed (50-55mph mostly), I'd come to a stop sign or stop light, and then when it was time to go, suddenly the engine would only put out low RPMs for about 15 seconds before starting to push the bike at speed.

Several possible causes:

• Fuel system problem, maybe it's time to replace the fuel filter, maybe the carb is developing some varnish and needs to be cleaned, etc. That seemed most likely.
• Something's wrong in the CVT -- worn belt, clutch spring tension wrong, worn rollers, etc. Very unlikely, since I had the variator upgraded and a kevlar belt put in less than 2,000 miles ago.
• A "heat sink lean bog" -- the engine block is getting hot enough that it's thinning/creating bubbles in the fuel in the fuel that's in the carburetor bowl, so the bike bogs until fresh, cooler fuel flows into it.

So, step one, order a fuel filter and change the old one out.

I ordered a fuel filter. It arrived.

I started pulling shit off the bike -- the storage box and the piece in front of the engine -- to get at the fuel line and trace it to the filter.

Hmm ... there IS no fuel filter. Which seems weird. I've changed the fuel filter on a 50cc scooter, I know there must be one. Help, AI! Turns out it's fairly common on 150cc GY6 short case machines to just not have one.

So I put the shit back on the bike. I will probably pull the shit back OFF the bike at some point and run all new line with an inline filter ... someday, not today.

I really would rather not pull the carb unless I absolutely have to. So I have some SeaFoam SF16 Motor Treatment Additive on the way. I've had that particular brand recommended by several people I know for getting ALL the crap out of a carb and motor. It arrives tomorrow. I'll add it to the tank, put a couple of miles on the bike at "city street" speeds by taking back roads before hitting a country highway, running it wide open for about 10 miles, and seeing what it does after a stop.

That said, I think it just might be the "heat sink lean bog." In which case the solution involves putting some insulation between the engine block and the carb.

If it's the CVT, I'll find out when I take it in for its 3,000 mile service, which is overdue by a couple of hundred miles anyway.

I actually kind of like wrenching on a bike, but I do also find it scary and I don't have a garage or "work on vehicles" area set up at the new place yet. I need to adjust the KP Mini for chain stretch, too, and haven't figured out a good way to get the rear wheel elevated (it doesn't have a center stand and I haven't bought a motorcycle stand ... yet).

But all of that is going to occur after or in between finishing the tent deck and getting the tent up, furnished, and operational. I've got a 5 x 7 Persianish-looking rug on the waym and expect to end up with three more in that size, plus smaller ones, plus a chair mat, by way of floor coverings. I've got a new desk still in the box that I got a deal on several months ago. I'll probably also look for a small game table and a couple of chairs. That kind of thing. All of which I was planning to do in late October or early November when the weather is better, but hey, now that I'm on it I guess I'll stay on it.