Dies after idle and hesitation throttling up

[JKR]

Hey all. During the colder months my RX3 would sometimes start, idle for a moment and then die. Sometimes it was hard to get started after but most times would start and stay at idle after first or second attempt. It's warm out now and it started exhibiting the same behavior. But this time seems harder to get it to start and stay at idle. Talked to Gerry and thinking maybe a voltage issue? Anyhoo, I dont have a volt meter but am borrowing one. I did re-tighten my battery terminals and was able to start the bike 4 times in a row with out dieing after initial idle. This morning it died once and then seemed to be ok. I also feel like at around the 5-6k rpm that I feel a slight hesitation as I throttle up thru the gears. I dont hear an engine pitch change, just a hesitation. Any feedback appreciated. Thx!!

[BlackBike]

Some info discussed on the csc blog

http://californiascooterco.com/blog/?p=24180

[2LZ]

Originally Posted by JKR

Hey all. During the colder months my RX3 would sometimes start, idle for a moment and then die. Sometimes it was hard to get started after but most times would start and stay at idle after first or second attempt. It's warm out now and it started exhibiting the same behavior. But this time seems harder to get it to start and stay at idle. Talked to Gerry and thinking maybe a voltage issue? Anyhoo, I dont have a volt meter but am borrowing one. I did re-tighten my battery terminals and was able to start the bike 4 times in a row with out dieing after initial idle. This morning it died once and then seemed to be ok. I also feel like at around the 5-6k rpm that I feel a slight hesitation as I throttle up thru the gears. I dont hear an engine pitch change, just a hesitation. Any feedback appreciated. Thx!!

Ya know.....this has been an ongoing issue for most of us from time to time and I've noticed it on both of mine, the blue one not so much but the white one definitely.

Of course, make sure your valves are adjusted properly and (as you've done) make sure your battery terminals are clean and tight. I put dielectric grease on mine.

Another thing that I've noticed with both of mine and that has to do with "battery health". When the bikes sit a while, the symptoms will act up on both. Stalling and noticeably harder starting. Especially the white one I have to crank for a while, when cold....BUT....this Winter I've had them both on float chargers for the first time, and they both fire up quickly and stay running now.

I'm really starting to think that it's a voltage issue more than anything. I think these things need "max voltage" to run and function properly all the time, thanks to the computer controls and fuel injection.

I'm really thinking it could be a combo between valves and a good, strong battery that's well-connected.

[BlackBike]

With all electronics... best practices are to verify voltage first then continue downstream. When you do your next valve job , I would disconnect battery , verify both connected and disconnected voltages, then check and reseat as many connectors as possible with voltage off. Connectors can be deceivingwhen plugging in ,may actually become misaligned and push a pin out of the connector housing. Rare but true and have seen it happen much to my bad luck in fixing stuff. Not saying this is the problem but you have to check those pesky electrics in a f.i. /vibration situation. Also some of those modules just start experiencing intermintant issues and just hav to be tossed out and replaced sometimes. (ie throttle position sensor etc.)

[JKR]

Thx for the input guys. Got a tester and will be checking things this weekend. I too think these are finicky about voltage. Gonna work it down stream as suggested and go from there.

[pyoungbl]

JKR, I fitted a voltmeter to my Zong about a year ago. I get consistent voltage readings in the 14V range. That tells me that the basic system is sound. You might have some connection issues. I'd check the connection to the voltage regulator (actually regulator/rectifier) and then consider a new battery.

Peter Y.

[JKR]

Just wanted to update this. Turned out to be a combination of spark plug and water in the fuel. I went through a huge thunder storm a couple weeks ago and was basically riding 10 miles in a waterfall of rain. Never seen anything like it here in western Wa in the 48 years ive been here. Long story short, changing the spark plug (10000 miles) took away the slight surge issue and fortunately the water in the tank is gone along with the starting issue

[SpudRider]

Thanks for posting the update. I'm glad you solved the problem.

[rjmorel]

Originally Posted by JKR

Just wanted to update this. Turned out to be a combination of spark plug and water in the fuel. I went through a huge thunder storm a couple weeks ago and was basically riding 10 miles in a waterfall of rain. Never seen anything like it here in western Wa in the 48 years ive been here. Long story short, changing the spark plug (10000 miles) took away the slight surge issue and fortunately the water in the tank is gone along with the starting issue

Good reminder for all of us JKR if caught in a deluge, problems with water sneeking into the tank can make motor run really weird like electric issues in following weeks. Not necessarily during that ride. So when riding in wet weather I run some additive in the following days that will get the water out. I've been caught in down pours for hours on end and water does get into the system somehow. rj