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improving throttle control at low RPM's??

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How can I improve my throttle control from idle (~950 rpm)to 1800 rpm on my BF30's?I can't geteven acceleration in this range and it's really frustrating me when pulling baits.
Any input will be greatly appreciated.
 
Hi. A few more details will help. First thoughts are
are your throttle linkages adjusted correctly?
are the linkages and throttle cams in good condition?
do you have 2 engines and struggling to keep the rpm balanced?
 
skronkman said:
Hi. A few more details will help. First thoughts are
are your throttle linkages adjusted correctly?
are the linkages and throttle cams in good condition?
do you have 2 engines and struggling to keep the rpm balanced?
Click to expand...

Thanks for the reply.
Yes, the linkages are adjusted correctly.
The whole set up is about 5 months old so I'd say everything is in excellent condition.
Yes, it is a twin engine set up and it is a struggle to keep the two engines balanced at rpms lower than 1800 rpm. It's a struggle to keep a single engine steady at rpms less than 1800 other than idle.
 
What is your max cruising rpm on both motors at full throttle?
Do your engines idle smoothly?
Are your motors 2014 models?
im a little short of ideas for you at the minute but all this info should help when some of the other folk on here come online.
 
Another thought, are your tachos reading smoothly? Do they bounce around and drop off sometimes around a certain rev? Can you actually hear the motors rpm fluctuate around or are you using the tacho as your guide? I'm wondering if it's actually the motors or the tach that is really the issue. Are your tachos honda or another brand? The 3 cylinder motors have caused some tach confusion in the past.
 
skronkman said:
What is your max cruising rpm on both motors at full throttle?
Do your engines idle smoothly?
Are your motors 2014 models?
im a little short of ideas for you at the minute but all this info should help when some of the other folk on here come online.
Click to expand...

I'm getting around 5800 WOT.
Yes, the engines do idle smoothly.
Engines are 2011's

skronkman said:
Another thought, are your tachos reading smoothly? Do they bounce around and drop off sometimes around a certain rev? Can you actually hear the motors rpm fluctuate around or are you using the tacho as your guide? I'm wondering if it's actually the motors or the tach that is really the issue. Are your tachos honda or another brand? The 3 cylinder motors have caused some tach confusion in the past.
Click to expand...

Yes the tachs are reading very smoothly.
I can hear the engines fluctuate as the tach does. The tachs are Honda tachs made by Teleflex.
The issue I'm having is that there isn't enough control/sensitivity between the shifter and the throttle linkage on the engine to have control at low rpm's (idle to 1800 rpm).
 
Things are sounding as they are suppose to be other than your lack of sensitivity. I know they can be pretty sensitive to throttle changes when in neutral but under load you should have more control. Perhaps others on here will have some more suggestions. Sorry I couldn't be more helpful.
 
It sounds like you should take it back to the selling dealer. Can you tell if maybe just one of the motors is running erratically? Have you checked to see how each one throttles up when it is running by itself? That might help you narrow down where the troubleshooting should start.

I also think like skronkman, that the linkages may not have been synchronized on each motor. Not motor to motor, but just on the each of the motors themselves.

I would also see if the dealer vacuum balanced the carburetors before delivery. They are supposed to come balanced from the factory, but many times they are not. The dealer should at least check each multicarbureted motor before delivery to the customer. As an FYI, if the dealer is not up to speed on how to balance the carbs, they do have to clamp off three hoses that go between the carburetors, otherwise, it will look like the carbs are balanced when they are not.

Other than an odd spot here and there, those motors should have smooth acceleration.

Check your oil level and make sure that it is not too high...ideally about 1/4" below the full mark.

Pump a sample of your fuel into a glass jar and see if there is any water in it.

Check your spark plugs to see if they are NGK or Denso. If they are Denso, replace them with NGK's DR7EA. Densos tend to fail much earlier than they should.

It is also possible (although not very probable) that one of your thermostats is stuck open. These motors do not like to idle when they are not warmed up. The 30s' thermostat starts opening around 162 deg F and is fully open at 180 deg F. If the thermostat is stuck open, it will run too cool. If you have a handheld temperature gun, measure it at the thermostat. It is just to the left of the top spark plug.

Fuel, temperature and carburetor balance are three of the key elements at the rpms you are trying to run.

Mike
 
hondadude said:
It sounds like you should take it back to the selling dealer. Can you tell if maybe just one of the motors is running erratically? Have you checked to see how each one throttles up when it is running by itself? That might help you narrow down where the troubleshooting should start.

I also think like skronkman, that the linkages may not have been synchronized on each motor. Not motor to motor, but just on the each of the motors themselves.

I would also see if the dealer vacuum balanced the carburetors before delivery. They are supposed to come balanced from the factory, but many times they are not. The dealer should at least check each multicarbureted motor before delivery to the customer. As an FYI, if the dealer is not up to speed on how to balance the carbs, they do have to clamp off three hoses that go between the carburetors, otherwise, it will look like the carbs are balanced when they are not.

Other than an odd spot here and there, those motors should have smooth acceleration.

Check your oil level and make sure that it is not too high...ideally about 1/4" below the full mark.

Pump a sample of your fuel into a glass jar and see if there is any water in it.

Check your spark plugs to see if they are NGK or Denso. If they are Denso, replace them with NGK's DR7EA. Densos tend to fail much earlier than they should.

It is also possible (although not very probable) that one of your thermostats is stuck open. These motors do not like to idle when they are not warmed up. The 30s' thermostat starts opening around 162 deg F and is fully open at 180 deg F. If the thermostat is stuck open, it will run too cool. If you have a handheld temperature gun, measure it at the thermostat. It is just to the left of the top spark plug.

Fuel, temperature and carburetor balance are three of the key elements at the rpms you are trying to run.

Mike
Click to expand...

Hey Mike thanks for the wealth of information.
I'll try addressing them as you listed.
What is happening is that once either engine is shifted into gear (idle) I can not throttle up smoothly/gradually to increase rpm. I ease up slowly but when there is a response at the linkage it's in the 1400-1600 rpm range then I have to back off but when I do I'm back at idle (fades). It seems like a mechanical issue, maybe binding?? No problems with the rest of the rpm range.
 
Can you pop the cowling off and watch the linkages moving while you are shifting in and out of gear and throttling up/down? You may need a mate to lend a hand at the helm while you are watching the engine. No need to start the motors as you are just looking for smooth operation and no sticking or catching.

Is your throttle control box is the original honda unit for your motors?
 
skronkman said:
Can you pop the cowling off and watch the linkages moving while you are shifting in and out of gear and throttling up/down? You may need a mate to lend a hand at the helm while you are watching the engine. No need to start the motors as you are just looking for smooth operation and no sticking or catching.

Is your throttle control box is the original honda unit for your motors?
Click to expand...

I'll have to find me another set of eyes to help me over the weekend.

Yes, the control boxes are Honda and came matched with my engines.
 
Look to see that the gear shift and throttle are not jamming up together, that for a little movement at the control box you get a little movement at the engine linkage, etc. you even want to try disconnecting the linkage at the motor and try and manually move the throttle cam to see if you can hold revs in the low range (engine running) and make sure nothing is stiff, sticking or otherwise difficult to move.
 
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