Hard Starting ST1100

[Bush]

I've heard of these couple tubes called 'drain tubes' in the carb(s/assembly?), but I don't actually know what/when they do whatever.

They ARE there to drain fuel away, but only when you open the float bowl drain screws, provided so that you can empty the carbs for storage purposes, or during a rebuild. The result of not draining the carbs for long storage periods is what we see happened to Tmac79 above.

 

[Jim Van]

If you can hear the fuel pump "buzz" for a few seconds after the key is turned on, and if you repeat turning the key OFF & ON a few times and the pump "buzzes" each time, the fuel bowls will be filled ( for sure) at that point. If the bike won't start, IMHO the problem isn't the fuel pump relay.

Th further troubleshoot, hook up a voltmeter to the fuel pump wire and measure the voltage. You could do this also while riding the bike, too.

The fuel pump hardly puts out any pressure. Occluding the fuel line with a finger is certainly doesn't mean the pump is bad. It only puts out about 1 psi.

See : http://home.insightbb.com/~mmartin36/FPDiagnostics.htm

You could also do a compression check, just for S&G's. It doesn't take long to do. Maybe the mechanic actually knows what he is talking about.

BTW, To drain my carbs at the end of the season, I disconnect the electrical line to the fuel pump and then start the bike and let it run until it starts to sputter. At that point I turn the choke on to get it to run a little longer until it dies. I took the carbs off to work on them last spring, after I did the preceding at the beginning of winter, and the bowls were empty. So the procedure seemed to do a good job draining the carbs without the hassle of getting to the drain screws.

 

[Grabcon]

Well folks I appreciate everyone's help on trying to get the bike running again.

I got my new used Fuel Cut Relay and she breaths fire again. I will start it again in the morning when it is cold to see if it true success. I am not a 100% convinced that the fuel pump may have issues but for now I have a grin ear to ear.

Thanks again.

 

[Doodaa]

Good to hear, hope ya fixed it.

 

[Doodaa]

Well folks I appreciate everyone's help on trying to get the bike running again.

I got my new used Fuel Cut Relay and she breaths fire again. I will start it again in the morning when it is cold to see if it true success. I am not a 100% convinced that the fuel pump may have issues but for now I have a grin ear to ear.

Thanks again.

Is the grin still there ??

 

[Grabcon]

Yes it has been starting but not as nicely as it should. My wife's st1100 starts with one or two turn overs and it runs nice without holding the throttle. Although with that said this my ST has never really idled well when the motor is cold. I always have needed a throttle assist to keep it going until it was warm. I just thought that was the way they were until I got my wife's bike.

It is turning cold (30s) again and I now have a week plus off so most likely I will tackle the valve clearance check since that has not been done since I got the bike. I bought the bike with 16k on it in August of 2011 and now there is almost 53k miles so I am guessing that the PO never checked them. So it is time. If for no other reason than to eliminate that as an issue.

The rub that I have is that this bike performs much better than my wife's bike. Better top end, better acceleration, just better overall performance, and my wife's bike runs very well. Hers is a 2000 with 36k miles and mine is a 1991. So hopefully I will get this squared away in the next couple of weeks.

 

[Doodaa]

Yes it has been starting but not as nicely as it should. My wife's st1100 starts with one or two turn overs and it runs nice without holding the throttle. Although with that said this my ST has never really idled well when the motor is cold. I always have needed a throttle assist to keep it going until it was warm. I just thought that was the way they were until I got my wife's bike.

It is turning cold (30s) again and I now have a week plus off so most likely I will tackle the valve clearance check since that has not been done since I got the bike. I bought the bike with 16k on it in August of 2011 and now there is almost 53k miles so I am guessing that the PO never checked them. So it is time. If for no other reason than to eliminate that as an issue.
The rub that I have is that this bike performs much better than my wife's bike. Better top end, better acceleration, just better overall performance, and my wife's bike runs very well. Hers is a 2000 with 36k miles and mine is a 1991. So hopefully I will get this squared away in the next couple of weeks.

If it runs that well otherwise, maybe you want to peek at the operative functionality of the "choke"-fuel enrichment and compare the movement or adjustment differences between your two motors. At a minimum, see if adjusting it for more "choke" lessens your symptoms. My "choke" makes a huge difference in cold starting and I seldom need to have it on at all more that 15-20 seconds. It's a 93 with 58K miles, cold starts as cold as I want to run it. :
Minimal cost and effort compared to "tackling" valves. JMHO

 

[Grabcon]

I agree that is an excellent suggestion. I will have to do that when my wife isn't around. She may think I am swapping parts. I have to back my choke off right away or it won't run, to about 3/4 position. Then I put the throttle lock on for a few minutes until it gets to that special point in temp to stay running.

 

[dwalby]

I have to back my choke off right away or it won't run, to about 3/4 position. Then I put the throttle lock on for a few minutes until it gets to that special point in temp to stay running.

Hmmm, this never got mentioned before, I always set mine to 3/4 position before starting the bike, never to full choke. Not sure why I do that, just been doing it for 16 years so the original reason escapes me, but I'm guessing it probably didn't run as well in full choke mode either. However, mine fires right up and requires no throttle to keep it running. At 3/4 choke I get high idle immediately and it runs on its own, then after 30 seconds or so I turn the choke completely off. You might want to try manually moving the choke lever without the cable attached (can't remember if you can get to it with the airbox attached though) and see if experimentation with that provides any new info. Also, if your idle is bad when cold, try turning the idle adjustment wheel in the gas cap area up a little bit, that should help, but you may have too high idle when it warms up. Also, have you checked carb sync? That can affect idle too, but in my experience even if its significantly out of spec my other bikes always idled fine regardless. But that is something that will affect the idle in theory, so worth checking if you can.

Finally, valves should have nothing to do with this, but if you have 53k without ever checking them then that's reason enough to do them.

 

[Grabcon]

So my friends on the ST-Owners Forum, I think the problem is finally resolved. But before I reveal what resolved the starting problem let’s do a review of symptoms. As this post went on other questions were asked and other symptoms were identified, adding to the original symptom.

1. Starting progressively has gotten worse over time
2. High RPM missing
3. Poor gas mileage
4. Looked like a fuel issue, but tests did not confirm
5. Bike started and ran, but as I stated I was not a 100% that what I had done resolved the problem after the second relay was put in. The next day it did not run again.
6. Never really idled well when the motor is cold. I always have needed a throttle assist to keep it going until it was warm. I just thought that was the way they were until I got my wife's bike.

So as a recap several things were done to help diagnose and resolve the hard starting. And I learned things along the way even though things did not necessarily resolve the issue but did eliminate items as I went along.

Learnings
1. Got a lot of valuable info from folks on the site.
2. Learned how to test and eliminate problem points based on forum experience.
3. Dug in deeper that I wanted to go, I guess the unknown is somewhat intimidating.
4. Learned how to take all Tupperware off. What a pain LOL.
5. Dug in to the valve clearance and adjustments and was successful.

So here is what the final resolution was to make the bike start and run like it should. The valves were way out of adjustment. All but one intake valve were tight enough where a 0.0015” feeler gauge would not go between the cam and bucket. All exhaust valves were at their low end of the range and a couple a bit tighter.
Because of the tightness and the inability to get a good initial clearance on the intake side this required two sessions to go through the effort of shimming. The first effort was to get a measurable clearance and the second to get it right.

Was this hard no intimidating at first yes. But it was overall an easy thing to do.

So what was the result. The bike started with full choke and no throttle and a tap of the starter button, it had a high idle, (which I have never had on this bike), it ran smooth and quiet. I have not had it on the road but I am sure all will be fine when I finish up the rest of the things, carb syncing, oil change, etc.
And I owe an apology to the Honda mechanic for not trusting his original diagnosis of valve clearance adjustment.

Thanks again to all and have a great rest of the holiday season.

 

[Doodaa]

Thanks for the excellent description and resolution of your troubles. Glad you got it fixed and posted your solution. You've added some positive info to this forum and I, for one, appreciate it. Thank you and holiday best wishes to you.:bow1:

 

[dwalby]

The valves were way out of adjustment. All but one intake valve were tight enough where a 0.0015? feeler gauge would not go between the cam and bucket.

And I owe an apology to the Honda mechanic for not trusting his original diagnosis of valve clearance adjustment.

WOW! Never seen any bike do that in 53k miles (or any mileage for that matter) in my life. Wonder if someone had mis-adjusted them previously, or if you have some issue with the cylinder heads allowing the valves to pound into their seats? A re-check after 5-10k miles might be worthwhile (recommended interval is 15k). Very unusual, but glad you seem to have found the cause.

 

[Grabcon]

There is one other notable symptom, but very subtle. The mufflers have condensate weep holes in the bottoms, prior to making the valve adjustment when it was running there was a fair amount of condensate coming from the weep holes. As the motor warmed up the condensate stopped. That has now stopped. Yes it was condensate and not raw gas for those that would ask.

I don't have any history on the bike so no records as to the maintenance on the first 16k miles. So I have know idea if there even was an initial valve check.

This has been an interesting journey and it will make me do the valve clearance check on my wife's bike after mine is back together.

 

[Doodaa]

I believe that condensation is a normal part of the warm up process for most internal combustion engines. As to the amount and length of time this is apparent would depend on a lot of variables, but I wouldn't be concerned if you see it.

 

[Grabcon]

I understand that condensate is part of the process but going from puddles of moisture to nothing is quite a change.

 

[Grabcon]

Finally I got to do a 60 mile test ride. The bike runs great. smooth power, no jerkiness, no high end rpm missing. I am happy with the results and believe that the valves were the issue all along. Thanks again all for the input. Oh yea it now starts every time cold or hot.

 

[winston lee]

Winston lee ,from down under in Western Australia.
I do not have any background with the .1100, but have in my stable two 1300's
This probably will have nothing to do with helping to resolve your starting problems but there are some very simple tests that i do when ever I come across any sort of similar problems.
They are,
Battery voltage test, first at rest (no load), and then under full load, (lights on and cranking the motor)
If the bike can be started from cold , run it for a few seconds , then shut it down and then do a finger touch to each of the exhaust pipes as close to the head ports as possible, this will tell you if each and every cylinder is firing.
Then if nothing untoward is showing up, I then take a very careful look at any wiring that I can easily access and check for any sort of damage, ie chaffing, loose and or corroded connectors , and at the same time inspect and clean any earthing points or joints.
Most of the intermittent electrical faults that I have ever had were eventually tracked down to a bad earthing problem.
I have found that these sort of checks have been most helpfull for me over the last 54 years that I have been riding and maintianing my various rides.
Cheers to all,
Winston Lee

 

[Grabcon]

Winston, thanks. If you look a little deeper in the thread the issues was the bike badly needed a valve adjustment. Everything on the intake side was very tight.

 

[winston lee]

Hi Grabcon,
I got that thanks,
and I was not trying to pre emt what was going on there and I realized that the crisis for you was over.
What I was trying to impart was, that I have found that those few basic steps that I suggested can at times be very helpful in isolating and or diagnosing some problem areas .
At the very least they should enable the elimination of some suspect areas, especially as I have found that sometimes there can exist more than one probable , (and compounding), possible cause for the, (failure), poor performance and then the malfunction can become very confusing and hard to diagnose .
I am glad that you got the problem resolved.
Cheers, Winston Lee , Western Australia

 

[Grabcon]

Winston Thanks much. You are right with hard to diagnose. I tried to eliminate the obvious and easy things first. But honestly I was fairly surprised that the valves were tight and that it was fairly easy to adjust once you get over the intimidation of pulling the cams. But I must say it was music to my ears after the adjustment that it started immediately.