Hard Start

[Revvv]

I have an interesting delima that I have never had before. Most likely because I have never had the bike get hot for very long.

Tonight while at the track I sat with the bike running for a while. Once the fan kicked in I allowed it to bring the temp back down and then I shut everything off. Within a couple minutes I needed to start the bike again, but it refused to start. It seemed as if the compression was too high or that the battery was dead. It would barely turn a couple revolutions and then the starter couldn't turn it any more.

After I allowed the bike to cool for about 20m minutes I fired it up like normal. You would have never thought there was ever a problem.

I even ran it down the track a few times just for the hecl of it. It has been running good and strong all night.

Once it builds up heat though it refuses to start up without a bit of hesitation.

 

[NightCrawler]

The same exact thing happened to me, oddly enough at the local drag strip. I was actually getting ready to stage when I tried to fire it up. It acted as if the battery was dead, just as you said. On the 3rd try it fired right up after switching off my high-beam and utilizing the fast idle.

 

[Revvv]

(NightCrawler @ May 31 2007,23:56) The same exact thing happened to me, oddly enough at the local drag strip. I was actually getting ready to stage when I tried to fire it up. It acted as if the battery was dead, just as you said. On the 3rd try it fired right up after switching off my high-beam and utilizing the fast idle.

Now there are 2 of us with the issue. Anyone got a reason for these strange drag strip antics.

 

[rockadaous]

sounds like you need the 24v start system. tiger racing has the bracket.

 

[GSXTacy]

What year bikes. Almost sounds like vapor lock. Do you have external fuel pumps?

 

[NearDeath]

sounds like vapor lock...

 

[NightCrawler]

Mine is an '05.

 

[Luvanicebum]

(GSXTacy @ Jun. 01 2007,09:32) What year bikes. Almost sounds like vapor lock. Do you have external fuel pumps?

+1

 

[Revvv]

03 here.

As for the 24 volt starter, a stock Busa shouldn't need a 24 volt system.

How could vapor lock cause the bike to turn over slow or not at all?

 

[300Busa]

Next time it happens, open your fuel cap and relieve the pressure in the tank. Then start it up.

 

[Professor]

Original Batteries?

 

[Revvv]

(Professor @ Jun. 01 2007,11:07) Original Batteries?

I"m not sure. I do know that the battery holds and keeps a charge. Every night when I place it on the tender itsays it's charged.

 

[Charlesbusa]

On my 2002, I always had that problem with the stock battery.

Then I bought the high output battery from schnitz racing, 235 cold cranking amps, and have never had the problem again.

The stock battery is weak...

 

[Charlesbusa]

(Revvv @ Jun. 01 2007,13:03)

(Professor @ Jun. 01 2007,11:07) Original Batteries?

I"m not sure. I do know that the battery holds and keeps a charge. Every night when I place it on the tender itsays it's charged.

The stock battery only puts out something like 160CCA.

Its just too weak when the bike is hot.

 

[Professor]

As a battery gets older its Cranking amps goes down, even when fully charged. The engine is harder to crank when hot. I suspect the battery is not up to snuff. Take the battery to an autoparts that has one of the more advanced testers. It should be putting out about 175 Cranking amps.

 

[Professor]

(Charlesbusa @ Jun. 01 2007,15:12) The stock battery only puts out something like 160CCA.

Its just too weak when the bike is hot.

I agree the stock battery is a bit weak. I swapped mine this year with a YTZ14S which is rated at 220 CCA. At my last race I they were hot lapping us in the 1/4 finals.

On the last few runs, I made a passes at:
8:21PM
8:27PM
8:35PM
8:44PM
8:54PM

You can count ~2 minutes to pickup your slip and make it back to the staging lanes. Another 45 seconds I have the key on to heat the O2 Sensor, 1-2 minutes after starting to get to the burn out box and burn out.

That is pretty hard on the battery, and mine started every time. I may just swap it at the beginning of each year to keep a fresh one.

 

[BusaWhipped]

The resistance in the starter goes up with the temperature, so it takes more current to start it when its hot. Hard strating hot is a sign of the beginning of end of your battery.

 

[tommyboy]

Has happened to my 2005 bike many times when the outside temp goes up and I try to restart the bike after say 20 min of sitting after a ride. The engine detonates prematurely and kicks back on the starter. The impression is that the battery is bad. I will agree that a more powerful battery may have the juice to force the engine to keep rotating. I can only assume the ECU is not retarting the timing properly when the engine is already hot.

 

[Revvv]

I just ordered a new battery so I will definitely know if that's my real problem in a day or so.

 

[Professor]

Be sure and let us know.

Did you order a 14s ?