Thanks for that explanation. Next time I’m in there I’ll see what the balance is like.
Engine noise under load - is it normal?
- Thread starter Helitronix
- Start date
Yes, I thought that maybe “start
Valve” was a Honda naming thing.
I did describe the noise in my first or second post; it’s like a pronounced meshing of straight cut gear teeth, under load at lower RPM. It still
Pulls cleanly and with authority, only with this grumbling noise. My 1100 does not do this at at all, and I ride them both the same way. I’ve never ridden another 1300 so maybe
It’s just wear and tear on this old 92,000mi bike. But my 1100 has 72,000 so not too far behind.
While your starter valves (throttle bodies) (sic)
May need to be serviced and / or adjusted, I believe your noise issue is your counter balancer adjustments are off.
This is about a 10 minute job, and all you will need is a 10mm wrench and a large flat blade screwdriver.
The bike must be stone cold, and you will have to soak the adjusters with penetrating oil the night before.
Just do the upper one, left until you meet slight resistance, the back one graduation (dot/line) then do the bottom one right until you meet slight resistance, the back one graduation, only this time use the LINE and not the dot (important).
Stop there, and do NOT start the bike and try and adjust things by sound or your adjustments will be off and all over the place.
Check the article section.
When these are off/loose your bike will make the noise you described.
May need to be serviced and / or adjusted, I believe your noise issue is your counter balancer adjustments are off.
This is about a 10 minute job, and all you will need is a 10mm wrench and a large flat blade screwdriver.
The bike must be stone cold, and you will have to soak the adjusters with penetrating oil the night before.
Just do the upper one, left until you meet slight resistance, the back one graduation (dot/line) then do the bottom one right until you meet slight resistance, the back one graduation, only this time use the LINE and not the dot (important).
Stop there, and do NOT start the bike and try and adjust things by sound or your adjustments will be off and all over the place.
Check the article section.
When these are off/loose your bike will make the noise you described.
I’ve already done the balance shafts. It made no difference. I followed the procedure described in the article section. Basically I turned them both (one at a time ) in the correct direction until the whine became obsessive, then turned them back just far enough for the whine to die off. I figured whine equals too tight so just “south”of whine was tight enough.
I would follow the service manual instructions, and do it cold, with the engine not running.
Moving stuff around with the engine running, and the heat of the engine expanding things, while listening to rattles is not always the best way to achieve the results you seek.
I’ve always had a problem with the last paragraph in the service manual for that reason.
That paragraph was meant to suggest that if the correct procedure did not correct the problem (due to extreme high mileage or wear) as a last ditch effort you may be able to get it close that way.
Everyone that I have adjusted stone cold removed all the noise, and vibrations etc.
Folks who did like you did (wandering/sound) never found any difference until they did it cold, with the engine off, then found they were 2-3 graduations (lines) off when finished.
It’s easy to do, won’t cost you anything, and may solve your noise issues.
Moving stuff around with the engine running, and the heat of the engine expanding things, while listening to rattles is not always the best way to achieve the results you seek.
I’ve always had a problem with the last paragraph in the service manual for that reason.
That paragraph was meant to suggest that if the correct procedure did not correct the problem (due to extreme high mileage or wear) as a last ditch effort you may be able to get it close that way.
Everyone that I have adjusted stone cold removed all the noise, and vibrations etc.
Folks who did like you did (wandering/sound) never found any difference until they did it cold, with the engine off, then found they were 2-3 graduations (lines) off when finished.
It’s easy to do, won’t cost you anything, and may solve your noise issues.
Next time I’m working on it I’ll try what you suggest. I had many problems just getting to where I could adjust the shafts, sheered retaining bolts, frozen shafts in the engine case, etc, it’s all in one of my posts in this thread with pictures. I had to buy new shaft locks and they are expensive. By then, I had lost all sense of zero, so running was the only option, but it wasn’t hot, I started it and began the process immediately. It was over in 90 seconds max.
BakerBoy
It's all small stuff.
Seems there's misunderstanding and propagation of incorrect info in the last couple days...
The starter valve is not a throttle body, nor is it an individual throttle body butterfly (plate) adjustment relative to other throttle body's butterflies. The starter valve is an 'automatic' throttle linkage shortener that is inline with the linkage that pulls all 4 throttle butterflies. When cold, the starter valve shortens, resulting in all butterfly plates being tilted slightly open. It's purpose is to, on cold start, cause the engine to run at elevated RPM for a couple minutes until the coolant temperature starts rising. It's an emissions thing, getting the catalytic converters up to temperature sooner.
The starter valve has nothing to do with engine noise when working properly, except the first couple minutes from a cold start at which point the engine simply runs at higher rpm (up to about 2000 rpm IIRC). Even if working improperly, it doesn't effect engine noise once throttle is opened and once engine is warmed. The starter valve has no job after cold startup (presuming it is working correctly). If it is working incorrectly, you adjust your throttle rotation slightly to compensate, without ever knowing it, and likely you've adjusted the idle rpm setting up so the engine doesn't die at idle once it is warmed up.
There also is a throttle body synch procedure that, for cylinders 2, 3, and 4, you can adjust the ever-so-slight air bypass around the butterfly plate in each throttle body so they match 1 air suction. That throttle body synch does NOT adjust either the starter valve nor the butterfly plate position. That throttle body synch only influences how uniformly all 4 cylinders fire at idle, only affects the engine when warm, and has nothing to do with airflow through each throttle body once the throttle is opened any amount. It has no effect on engine noise (unless something really strange has happened, such as if the linkage to ONE throttle body is disconnected).
There's an inherent amount of engine noise in the St1300 engine. Most people assume that they need to adjust the counterbalancer shafts as a means to 'solve' inherent noise. There can be slight noise from the counterbalancer shaft gear meshing (backlash), but unless there's an outright failure of the counterbalancer bearings or gear, that's a very very very small amount of noise of the engine. Yes, perhaps adjust the counterbalancer shaft backlash, but if you've done it once, that's likely all that is ever needed for the bikes entire life (unless misadjusted previously).
The starter valve is not a throttle body, nor is it an individual throttle body butterfly (plate) adjustment relative to other throttle body's butterflies. The starter valve is an 'automatic' throttle linkage shortener that is inline with the linkage that pulls all 4 throttle butterflies. When cold, the starter valve shortens, resulting in all butterfly plates being tilted slightly open. It's purpose is to, on cold start, cause the engine to run at elevated RPM for a couple minutes until the coolant temperature starts rising. It's an emissions thing, getting the catalytic converters up to temperature sooner.
The starter valve has nothing to do with engine noise when working properly, except the first couple minutes from a cold start at which point the engine simply runs at higher rpm (up to about 2000 rpm IIRC). Even if working improperly, it doesn't effect engine noise once throttle is opened and once engine is warmed. The starter valve has no job after cold startup (presuming it is working correctly). If it is working incorrectly, you adjust your throttle rotation slightly to compensate, without ever knowing it, and likely you've adjusted the idle rpm setting up so the engine doesn't die at idle once it is warmed up.
There also is a throttle body synch procedure that, for cylinders 2, 3, and 4, you can adjust the ever-so-slight air bypass around the butterfly plate in each throttle body so they match 1 air suction. That throttle body synch does NOT adjust either the starter valve nor the butterfly plate position. That throttle body synch only influences how uniformly all 4 cylinders fire at idle, only affects the engine when warm, and has nothing to do with airflow through each throttle body once the throttle is opened any amount. It has no effect on engine noise (unless something really strange has happened, such as if the linkage to ONE throttle body is disconnected).
There's an inherent amount of engine noise in the St1300 engine. Most people assume that they need to adjust the counterbalancer shafts as a means to 'solve' inherent noise. There can be slight noise from the counterbalancer shaft gear meshing (backlash), but unless there's an outright failure of the counterbalancer bearings or gear, that's a very very very small amount of noise of the engine. Yes, perhaps adjust the counterbalancer shaft backlash, but if you've done it once, that's likely all that is ever needed for the bikes entire life (unless misadjusted previously).
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Wow! Thanks for that common sense and clarity. I’m just going to accept that the 1300 is. Not as refined as the 1100, bizarre, I know, backwards advances from Honda. Honda is not infallible. Example, both models need a 6 th gear, 1300 should have a gear indicator, cruise control and traction control. All these technologies had been well known to Honda for decades before the 1300 came out. The 1100 (some models ) had traction control , why delete it from the 1300? It’s 20 lines of code max. And why do you have to remove the waterpump on the 1300 to change the clutch? The 1100 doesn’t need that. As I said Honda is not the perfect automotive juggernaut that people give it credit for. I guess a noisy engine “upgrade” is possible.
I think I know what noise you are talking about. Sounds like engine knock under load below 3K RPM?
My bike did that for a while and then stopped doing that and went back to being very smooth all the way down to idle. I think it is related to ignition timing. There was no FI light on. Nothing. And it was fine over 3K. Fuel made no difference. Regular or premium, ethanol free etc. I was going to take a look at it this winter during maintenance. Probably still will see what I can find if anything. Bad knock sensor or wire perhaps. I replaced the ECU so I hope it’s not that.
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jfheath
John Heath
Regardless of what some might say about the starter valve synchronisation, for me the improvement in smoothness, acceleration and fuel consumption was very noticeable.
The manual calls the items to be adjusted 'starter valves'..
I've already commented about the pinking noise under load of my pre 2008 model, and what I did to cure it: Ethanol free fuel. Higher octane fuel, 10w40 fully synthetic oil, new fuel filter. I think that I was at 40,000 miles before I had worked all this out and perhaps this was the real cure (ie to ride it for 40,000 miles, and it all goes away). I proved to myself that ethanol, octane and oil made a difference, as it got worse when I used ethanol fuel and semi-synth oil. I cannot undo the 40,000 miles that I did before I got it to go away. The owners handbook said that it is normal.
My 2009 model has never done it, but it seems to be tuned very differently.
The manual calls the items to be adjusted 'starter valves'..
I've already commented about the pinking noise under load of my pre 2008 model, and what I did to cure it: Ethanol free fuel. Higher octane fuel, 10w40 fully synthetic oil, new fuel filter. I think that I was at 40,000 miles before I had worked all this out and perhaps this was the real cure (ie to ride it for 40,000 miles, and it all goes away). I proved to myself that ethanol, octane and oil made a difference, as it got worse when I used ethanol fuel and semi-synth oil. I cannot undo the 40,000 miles that I did before I got it to go away. The owners handbook said that it is normal.
My 2009 model has never done it, but it seems to be tuned very differently.
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A problem with the vacuum tube on the MAF sensor would cause a lean condition which would cause engine knock under load at low RPM. My bike fixed itself, so perhaps the tube was partially blocked as that would cause a lean condition.
On a different subject, the starter valves do not effect the butterflies at all. They are called valves because they open and close small ports in the throttle bodies which flow additional air bypassIng the butterflies completely. They control engine idle rate, nothing else but are required when starting the engine without using the throttle, as they are the only means of supplying air when the throttle is closed. I think this confusion comes from the days of carbs which used a similar system to adjust the butterflies for idle control which unlike throttle bodies controlled both air and fuel.
On a different subject, the starter valves do not effect the butterflies at all. They are called valves because they open and close small ports in the throttle bodies which flow additional air bypassIng the butterflies completely. They control engine idle rate, nothing else but are required when starting the engine without using the throttle, as they are the only means of supplying air when the throttle is closed. I think this confusion comes from the days of carbs which used a similar system to adjust the butterflies for idle control which unlike throttle bodies controlled both air and fuel.
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Sometimes just washing the bike makes it run better and the sunshine brighter 
Claims of increased fuel mileage after a starter valve synch ....... how accurately was mpg tracked before and after? Is fuel consumption ever documented to make mpg claims believable?
Claims of increased fuel mileage after a starter valve synch ....... how accurately was mpg tracked before and after? Is fuel consumption ever documented to make mpg claims believable?
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More like Pilot screws on a CV carb, they adjust the amount of fuel allowed to bypass the butterfly for starting and low-speed operation.
jfheath
John Heath
Actually I don't think that is quite right either.
The throttle butterflies are fully shut (and sealed by molybdenum sealant) at idle, and they are only opened by the rider's hand.
The starter valves are the only source of engine air at idle. The starter valve opening amount is controlled by the wax unit (which pulls them further open for a fast idle when cold) and then the idle adjuster screw (which hold them partly open when warm). There is no connection between the starter valves and the throttle butterflies.
Synchronising the SVs will result in the same vacuum being drawn on each cylinder at idle, which should result in the steadiest idle as all cylinders should be firing evenly (assuming uniform spark, compression and fuel injection).
As the SVs are always open, their settings will have a small effect especially at small throttle openings, but little or no effect when the throttle is wide open. So you might expect smoother running at very small throttle i.e. cruising at low speeds, when the SVs are correctly set.
The effects of the last point are debatable. The passages for the starter valve circuits are tiny in relation to the intake tracts controlled by the butterflies. When the butterflies are eased open and air enters the venturi of the intake it's pressure rapidly lowers, much lower than that of idle air vacuum, and the idle air passages just can't pass much mixture into the intake which is hundreds of times larger in volume. Then the mixture differences between individual starter valves are so slight as to be lost in the overall mixture charge.
Bmacleod
Site Supporter
More to your point Dave... You mention a venturi. Back in the day, a carburetor had a venturi as it was necessary to create the vacuum to pull the fuel out of the circuits of the carburetor. The idle ports were right in the venturi so it was possible to get some residual effect on small throttle openings from the idle fuel ports in a carburetor. The Thing is a throttle body in a fuel injected engine has no venturi, meaning no low pressure area to draw air from any ports. As soon as the throttle starts to open, there should be no draw on the idle air ports. This why I struggle to understand how the idle air balance can have any effect on the engine performance beyond closed throttle, much like you.
When I have had the airbox off my FI bikes during a synch, the SVs make quite a loud hissing sound, so while I agree they are small, they seem to flow a decent amount of air. My recollection is that they are something like 4mm diameter. The other thing to bear in mind is that the opening created around the 36mm throttle butterfly is not proportional to the degrees opened. So 10 degrees open is around 0.1% of the WOT opening, 20 degrees is just under 2% and so on. So until the throttle is opened the SVs make up quite proportion of the air.
I made a rough calculation assuming 4mm for the open SV, and the SV would make up 95% of airflow at 10 degrees throttle, 47% at 20 degrees open, 23 % at 30 degrees open and 14% at 40 degrees open.
You may be surprised how often you ride the bike with such small openings.
I made a rough calculation assuming 4mm for the open SV, and the SV would make up 95% of airflow at 10 degrees throttle, 47% at 20 degrees open, 23 % at 30 degrees open and 14% at 40 degrees open.
You may be surprised how often you ride the bike with such small openings.
Bmacleod
Site Supporter
That is a valid explanation Terry. I guess the only way to know would be if one had a vacuum gauge hooked to the 5 way tee while riding. My experience with synchronizing my starter valves has always been "aha, 20 more HP. Can't wait to check my fuel mileage". Then when I check my fuel mileage and it's the same as before I tell myself "oh well I was getting rambunctious with all that extra horsepower it should be better next time". By the next time fill up comes I realize I don't have any more power snd my fuel mileage is the same as before... Lol.
But, I do absolutely agree that you should always check your balance whenever you're in there. I have had slight imbalances and when adjusted the bike definitely idled better but I didn't notice any difference at any other time.
But, I do absolutely agree that you should always check your balance whenever you're in there. I have had slight imbalances and when adjusted the bike definitely idled better but I didn't notice any difference at any other time.