I have been following your motorcycle adventures and your writings about motorcycle repair and I have nothing but marvel at your skills.
I have a KLR that has recently developed initial starting problems. Especially when it is cold, it is really difficult to start. SOmetimes I’d be trying 5-10 min in 20 or so deg temps to get it started. Other than that once it starts and it warms up it will start and run OK all day long. This problem became aparent to me a day after I changed my oil.
So far have looked at the spark plug, seems to look OK.
Do you have any advice on what might be causing difficult starting?
Hard starting can have a variety of causes.
Because it is so cold out when you are having trouble it’s likely just a couple things.
Compression. How is the compression? Get a hold of a compression gauge and check the compression of your motor.
What oil are you running? In 20 degree temps you aught to be running something pretty thin. I would read the recommendation in your manual for the best weight oil in your KLR for low temps. Cold oil means poor circulation means poor lubrication means low compression.
If the bike was cold starting fine before then your carb settings are likely ok. In cold weather you’ll want to run richer jets than in warm temps. In either case it’s not a bad idea to pull your carb and check the jets and choke passages to make sure they are clean.
First things first. Check your compression cold. Then warm the bike up and check your compression hot.