Hey guys.

Just when I thought I was finally ready to start riding for the spring... and now this.

A week ago I took the bike out with air filter removed/vacuum hoses disconnected. Ran like a champ. All I've done since then is put on a new chain and rear tire - and sealed airbox/filter/hooked up vacuum lines and now it backfires instead of starting.

I've saw a lot of posts about vacuum leaks causing backfires at rpm. Is there anything about sealing a vacuum leak that could cause my hurricane to backfire on startup?

On a couple attempts it did run for a few seconds. First time it died out before I could give it throttle. Second time it jumped quickly up to 5,000rpm so I killed it.

Also, it was 30 degrees colder than last weekend.

Please help - Would love to get on the road.

 

Turns out the choke was stuck halfway. Although not sure why having the choke at half would cause a backfire on cold start.

 

Wow. It's literally been something new every day this week. Resolved the starting issue (see above). Then I took the bike on a test ride and it didn't have enough power to cruise at 60mph in 6th gear. Ugh. pulled the plugs, they were all new. 3 and 4 had no carbon on them and smelled of gas and were wet. So I hunted down the spark problem, corroded wires. Started it up and it ran on four cylinders for the first time since I had it! Awesome, right? Wrong, now its blowing blue smoke very badly. Could it be that oil has just built up in the combustion chambers from not firing in so long? Or... do you think its more along the lines of rings or cracked head. I only ran it for ~30sec. Will try running it longer tomorrow.