Hard start

Hi I have a 82 xj1100 and all of a sudden it's hard to start first thing but once it does it runs great. And other times it starts just fine. So choke is working and when it does have problems starting its flooded when it does start. Could it be weak coils. I've sprayed water on them but don't see anything. But they are original. Any help would be appreciated

 

Could you give us a little history of the maintenance you have done on the bike? Sometimes if a bike is hard to start it is the valves out of spec. Have you done any work on the carbs? I will let you fill us in a bit.

 

I bought the bike last July not running. The guy had the head off of it for a bent valve. But he could never get it to run. He had the shims all messed up. So I shimmed the valves to correct clearance and went through the carbs. Rode it all of fall and winter and this spring with no problems. Now its hard to start. Even backfires sometimes. But once it starts it's good. Even on hot starts

 

And sometimes I can choke it like normal and it starts fine. But that's just a few times

 

I put 2000 miles on bike before this started

 

Did you check to see if one of the valves was actually bent? If it was...

 

The head was redone. So it had a valve job. As I said I've had no problems for 2000 miles

 

do a voltage drop test of the battery when trying to start cold

 

What does the inside of the tank look like? Do you have a in-line fuel filter and if so what does it look like? I hate to say it but if it is popping and running ruff again, could be the carbs or a vacuum leak.

 

Inside of the tank is clean. I have no inline filters. If that was the problem why does it run great once you get it running?

 

if the float needle cap(filter) is clogged it will starve a carb of fuel. the xj will start hard when cold but start easy when warmed up.
the xj will run very well with just 3 cylinders running. I have had this happen with 2 bikes it is noticably running less well but stills runs.

no fuel in a carb bowl is equal to a vacuum leak
check and see if all the header pipes are getting hot when bike starts and running. I use a temp gun you will see a considerable difference in the temp on a poor running cylinder

 

could also be one of your jets fell off in the bowl

 

xj1100 has the octopus feed for the fuel from tank you may want to have a look at that system as well

 

Okay I will check all of this. Thanks for your help

 

Hey just curious if you figured out what the problem was. Did you get it starting well?

 

I'll second checking your battery voltage while starting. My XJ11 will do the same thing when the battery is weak. Once a good battery is in it starts right up. A weak battery along with 35 year old wiring connections will drop the voltage to the TCI below 10.5 volts. The engine will turn but not start if the voltage is below 10.5.

 

2000 miles after a valve job almost time to check the shims again.

 

I had the same problem and someone suggested checking the voltage output at idle. I did and found it to be low--about 11.3 volts. I replaced the alternator brushes and that solved the problem. Voltage is now about 12.5 at idle and it starts easily again.