Back to Basics on an old Bike

I often find something that still doesn’t feel 100% right. These days, it has been the cold start and the choke. After the bike came out of restoration, it had a cold-start problem. The usual solution was to use the choke without throttle, and that mostly worked.

During the recent six-month service, I complained about it to the mechanic. He said he fixed it and asked me to continue using it as before. But then I couldn’t start by kicking. I had to push in 2nd gear to start it. Even after starting, it would cough and take a couple of minutes to stabilize. My initial doubt was the spark plug (whether it could generate enough spark), then the carburetor. The spark plug was good. Hot kickstart was working. The carburetor seemed fine based on all other parameters.

The only thing I found odd was that just a few meters of push would always start. But the bike would cough, and you could smell petrol after a push start. We have not changed the original Mikuni UCAL carburetors, and I had not used the choke in its previous life, even while riding in the cold mountains. So I went back to basics.

No choke, no throttle, kick, no start.

Again, no choke, no throttle, kick, it starts. That’s good news. I switched off. Came back hours later.

No choke, no throttle, one pseudo-kick, then one smooth full kick. It started like magic.

I could repeat this process many times, and it always worked, even on the coldest day.

So the choke settings are way off; it’s flooding the engine, and the kickstart couldn’t start it. But a pseudo-kick primes the dry engine without flooding, and then the next kick starts it easily. I need to fix the choke settings for days when I really need it.

Sometimes it is just back to basics.

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