BC Sport Bikes Forum banner

1 - 18 of 18 Posts

·
Linguistic Ninja
Joined
·
88 Posts
Discussion Starter #1
Ok.. two times now and it's pissing me off. It been at night where it's been coldish... start up bike with choke on.. warm up.. ok.. that's fine. Ride around a bit.. back off the choke a little...then when the engine gets really warmed up (the oil temp needle is to the point where i expect it to be after a long ride).. i back off the choke more. At this point, the engine will kinda... choke... and die.. a slow and painful death until it stalls.

I find i have to keep the choke at about the half way point so that it doesn't die. Is this normal?
 

·
Premium Member
Joined
·
11,195 Posts
For starters I'd say you got the right idea of how to use the choke but you may be easing it in over too long a time. Riding with more choke than you need can lead to carboned up plugs that tend to foul easier.

Another option is that you may have an air leak in the system for some reason downstream of the carbs.

If the bike was in storage for quite a while I tend to second Dalma's suggestion that the carbs need a good internal strip n' clean. But if the bike has been in more or less regular use this should not be the case.

I'd start with the plugs. Pull the old ones and check their appearance. I suspect they will be quite black with a sort of fluggy look and possibly have some little lumps on the ground electrode and possibly on the center. Or it may have a strong white look with very thin deposit around the area if. The first means it was too rich and the second means it was too lean.

If they fouled from being too rich then adjust your choke use behavior slighty, install new plugs and see how it goes.

If the plugs are strongly whitish with no real signs of any sort of buildup on the rest of the plug other than a thin black color around the spark area then check to see if you can find any sort of air leak in the lines or around the manifolds that connect the carbs to the cylinder heads. These connectors have been known to dry out and crack. Look for broken clamp rings on these joints as well. Check that any vacuum lines that connect to the carb synch nipples on the connector manifolds are connected to whatever they are supposed to connect to or that there's plugs over the test nipples.

If the bike runs strong up top but only has issues at idle then I'd suspect an air leak. It takes almost nothing at all to mess up the idle and make the bike stall. If you find an age crack in one of the rubber connectors then you can goop it up with high temperature silicone but be sure to order new ones soon. One crack is only the beginning.

Such cracks often occur when doing carb work where the carbs are forced out of and back into these connector manifolds but they can happen on their own if the rubber is in really bad condition.

PS: we always forget the simple stuff.... :D While you're looking around in there go over the clamping bolts, nuts and screws to ensure they are all at least snug. Nothing needs to be deathly tight but they all need to be snug. If you find any that have backed off for some odd reason or one of the little clamping straps broke then you likely found your air leak source.
 

·
FeAr FaCtOr
Joined
·
35 Posts
Since My girlfriend use to own the bike I did most of the maintence on the bike.

As far as I know it always ran smooth. I never ran the choke more than 5 minutes and never ran the choke when riding.

I suggest you start the bike ( cold ) for 5 minutes with the choke on and then turn off the choke get on and ride the bike up the highway or at least 15 to 20 minutes.

I agree with TeeTee you have fouled the pluggs up by riding with the choke on and she needs a good run before they will get cleaned off.

Have you played with the idler screw??? This may also fix the problem she may just be dropping just a little shy of the idle point. When warmed up just turn the idler up a notch until it runs smooth on it's own.

Hope this Helps.
 

·
Linguistic Ninja
Joined
·
88 Posts
Discussion Starter #6
I have not touched the idle screw

Bike has been used quite a bit and the plugs were recently replaced (thursday). I've been on 4 rides. 1 from the shop.. no prob. 1 in the snow.. where i kepted stalling. 1 at night again no prob and again the one at night yesterday where i had this issue.

Don't suppose anyone has a link to a pdf version of the ex500 shop manual eh? I couldn't find it in the sticky

Thanks for the suggestions guys... time to run out and go buy tools.
 

·
Premium Member
Joined
·
11,195 Posts
DaFonz said:
I have not touched the idle screw

Bike has been used quite a bit and the plugs were recently replaced (thursday). I've been on 4 rides. 1 from the shop.. no prob. 1 in the snow.. where i kepted stalling. 1 at night again no prob and again the one at night yesterday where i had this issue.

Don't suppose anyone has a link to a pdf version of the ex500 shop manual eh? I couldn't find it in the sticky

Thanks for the suggestions guys... time to run out and go buy tools.
OK, so it's a regular runner and it's a problem now and has new plugs.

So when you mentioned that it bogs and eventually dies what happens if you jazz the throttle a little? Does it sound like it's out of gas and stall anyway? Or is it just sputtering to a halt while trying to idle? And if you rev it a little does it come back to a steady idle within a couple of seconds or do the revs hang up there for a moment and then come down to idle speed? By a moment I'm thinking two or three seconds.
 

·
SuperStyling
Joined
·
3,098 Posts
I'm not sure if the humiditiy has any affect on starting of a bike. If you guys know, could you explain?

I notice the humidity has been preety dry lately. A couple days ago it was at 52% and my bike had some problems starting without choke and yesterday it started fine without it and humidity was like 70%?
 

·
Registered
Joined
·
1,368 Posts
Sounds like water in the fuel system. Drain your float bowls into a jar and see what comes out. You may have to take your tank off and give it a good cleaning to get water and crap out. Do you have a fuel filter? Nice to add one if you have room.
 

·
Premium Member
Joined
·
11,195 Posts
coolio said:
I'm not sure if the humiditiy has any affect on starting of a bike. If you guys know, could you explain?

I notice the humidity has been preety dry lately. A couple days ago it was at 52% and my bike had some problems starting without choke and yesterday it started fine without it and humidity was like 70%?
Only slightly. More water vapour in the air means there's less oxygen just because the water is taking up room that nitrogen and oxygen would normally use. This means that your mixture is very slightly more rich in the damp than in the dry.

If you insist on starting your bike with NO choke then yeah, it'll catch easier on a damp day than on a dry and cold day. But you ain't doing your battery any favours by asking it to crank a cold bike until it just happens to catch and run. Use the choke!
 

·
SuperStyling
Joined
·
3,098 Posts
DaFonz said:
Rode the entire day today... no problems.

WTF? This is such a weird problem
Maybe you were only riding your bike for 15minutes a day before? Bike was not running completely at operating temp?

I had some stalling problems with my bike too. Not sure if it was the choke or I just didn't ride my bike long enough everday. My commute time everyday was like 15minutes. The day before yesterday I rode my bike for 2 hrs and the next day that I rode it, it seemed fine.
 

·
Premium Member
Joined
·
11,195 Posts
If your daily ride is only 15 minutes and if it's in traffic with lots of idling then it's likely that you're not replacing all the charge in your battery from starting the bike. It's also likely that the plugs don't get a chance to really get hot enough for long enough to really burn off all the grunge from the initial cold running. Once or twice isn't a problem but if it's every day then it may build up eventually. It may be a good idea to take the long way home a couple of times a week.
 

·
Linguistic Ninja
Joined
·
88 Posts
Discussion Starter #15
TeeTee said:
If your daily ride is only 15 minutes and if it's in traffic with lots of idling then it's likely that you're not replacing all the charge in your battery from starting the bike. It's also likely that the plugs don't get a chance to really get hot enough for long enough to really burn off all the grunge from the initial cold running. Once or twice isn't a problem but if it's every day then it may build up eventually. It may be a good idea to take the long way home a couple of times a week.
Average ride for me is about 2 hours. ..I think you might be right though. I had absolutely no problems tonight either... oh well.. we'll chaulk it up to stupid grunge that was burned off
 

·
Ridin hard n dirty
Joined
·
4,080 Posts
Colder weather means the bike runs leaner...if you need to keep a partial choke to keep it goin turn your air/fuel screws richer...if you don't know what they are take it to Bill at 5th gear...
 
T

·
Guest
Joined
·
0 Posts
gas + cold and winter no rides = carb guck


Look into the tank for rusty resin bits i got that on the first day of spring real piss off... Had to Kcreeme my tank up clean the carbs and overhaul the beast good b4 it rode again only due to not filling all the way up to the top with gas before winterizing and i used stabil as well..
 

·
Banned
Joined
·
569 Posts
Problem gone? Sounds like water in the fuel. The water condenses from the air inside the tank, runs to the bottom, and a drop gets sucked into the fuel line, past the filter and sits on top of a carb jet or injector causing the intermittant problem you describe. The choke keeps the fast idle on and chokes it enough to keep it running. Eventually the water gets pulled through and consumed, and the problem leaves, till the next water is sucked in.

Don't take it apart, solve the problem with half a bottle of gasline antifreeze, or about 100ml of methyl hydrate. It breaks the surface tension of the water, allows it to absorb with the gas and be consumed by the engine harmlessly. Do it one in the fall and once in the spring as preventative maint.
 
1 - 18 of 18 Posts
Top