Just a quick question. If the wire from the water temperature warning light switch that plugs in to the bottom of the left radiator breaks, will this prevent the bike from starting? I just put my engine back together for the third time and it won't fire up. It turns when I push the start button but won't turn over. Any ideas?

 

Are you saying that the engine will turn over but will not fire? I think the switch is normally open so having the wire disconnected should not make a difference.

 

Correct, will turn over but will not fire. I was hoping you would say that it would make a difference so that it would be an easy resolution to why it's not starting.

Won't it kill the engine if it over heats or simply warn you that your engine is overheating. Is it part of the starting circuit? I would assume that if it was part of that circuit then it wouldn't even be turnover.

 

The temperature switches are not permissives or lockouts for starting, so they are not in the circuit. One switch turns on the fan and the other one turns on the warning light. Sounds like you are getting either no gas or no spark.

Pull the plug and crank, see if you get spark.

If you had the engine apart there are a number of things that would bugger you up. I'd go back and recheck any connections you might have disturbed.

Cheers,

Anthony

 

Radiator switches will not effect starting or running.

As Anthony says, spark or fuel most likely causes.
You say you've had the engine apart.
To what extent?

 

Umm What did you do ?

Or why did you have it apart?

David

 

I have been in the stages of puting the BB351 kit on my bike. I had it running but had a couple drops of coolant from the top cylinder head gasket. Took it down and re assembled following the manual specs for tightening the cylinder bolts. Had to take it down again since I believe the valves were hitting against the cylinder because I believe I didn't have the cam chain on just right, I swear I counted 32 spaces, but whatever. So took it apart again and made sure the cam chain was perfect and once again put it back together and here I am. Maybe the battery just needs to be charged up some more as it starts to die after trying to crank it for a couple minutes.

To put it mildly, I am starting to get pretty annoyed with this thing. It has been kind of a time suck for me lately, but what do you do. I probably should have just take it somewhere and told them to fix it, but I am not made of money and figured trying to do it myself would be cheaper. Now I am not so sure.

 

While you have the plug out checking for spark:

Do a compression check!


If you don't have the tool check, your local parts stores, sometimes they loan them.

 

So if I get the tool and check the compression and it's not adequate then what do I do? If there is that type of problem then I would rather just take it somewhere and have it checked and then fixed. And I tried suatering the wire to the water temperature sensor and now the sensor is turned on so whatever that means. It turns on as soon as I turn the key so I think the sensor is just bunk now.

I charged it all night and it didn't turn over this morning. I don't have the head pipe back on yet since I wasn't going to put everything together just to take it down again if it didn't work, but when I try starting it I am getting a gas smell in the air and that's about all I can tell at this point. I would assume you can damage a valve if it is slapping against the piston head, correct? I would assume that this would prevent it from starting since fuel may not be getting into the cylinder to fire, just a guess.

 

If your compression is no good either your piston rings are no good or your piston is cracked.

Since you hinted earlier that the timing may be off then low compression could be a result of the valves not being completely closed during the compression cycle.

Since the sensor is on all the time now, you may have melted the switch closed when you soldered it. The switch closes to bring in the light. Check the switch contacts with an ohmmeter and see if you get < 1 ohm. If so, your switch is no longer a switch but a jumper, and the fix would be to get a new switch or just disconnect the wires which would defeat the alarm. I would recommend picking up a new switch.