TR-1 optimum spark plug gap

[TeenGee]

I hope one of you has already done the experimenting with spark plug gap and found the optimum gap.
I just got my 210FSH back from the dealer servicing. Among other things, they changed the spark plugs. The port engine ran up to 7,200 rpm like before the servicing. The starboard engine maxed out at 7,000 rpm. I inspected the plugs and all but 1 were gapped to 0.028". Number 2 plug on the starboard engine was 0.030". I set it to 0.028".
The range in the manual is 0.028" - 0.031".
The service manual says the max rpm is 8,000.
I have read that high output engines run better with smaller spark plug gaps. I at about 115 hp from 1,050cc would consider the TR-1 as a high output engine. I'm wondering if a gap less than 0.028" would get more rpm from my engines.
Have any of you tweaked the spark plug gaps and gotten some more rpm from their engines?

 

[HangOutdoors]

You won't get to 8000, no one does. 7200-7500 is about it. Depending on engines, altitude and temperature. Check your oil levels. Should be half way between L and midway. so about a 1/4" or a bit more above L

In the spring in the great lakes, cold water cold air I have gotten 7,700 7500 now I get 7.300 7,500. One side will always be higher than the other.

Engines are sensitive to air pressure, humidity and Temperature. IF you are running in humid conditions knock a couple few hundred RPM's off. When I was down in Destin last month I lost a couple hundred RPM's a motor.

There has been a post or two of people hitting 8000 but most have never seen that. Not sure why that is.

 

[TeenGee]

That brings up another question. The operator's manual says to run the engine for 6 minutes (or 11 minutes if the temperature is below 68F) before checking the oil level. The service manual says to wait at least 5 minutes after the engine has been run to check the oil level.
So which is it? Or do I need to run the engines for 6 minutes and then wait for 5 before checking the level?
I'M SO CONFUSED.

 

[HangOutdoors]

I run mine for about 5 minutes. Usually on the water in a no wake zone that way I know the engines are sitting level when I check them. Otherwise, use a small level and level them front to back and side to side. Run for a few minutes to 5 minutes just to warm the oil. Then let it sit for a few minutes to let the oil drain back down and then check it. If you are out of the water, run them on the hose. engine on, hose on....... then hose off, engine off. I am sure you know, but just restating.

 

[HangOutdoors]

Also don't blindly trust the dealer service did everything right and filled the fluids to the correct level. Double check everything!

 

[TeenGee]

I had already changed the oil, so they didn't touch that.

 

[TeenGee]

I tried NGK Iridium plugs gapped at both the min and max gap. No difference in top speed.
As an aside, I connected a vacuum gauge manifold absolute pressure port of one engine to see if there is any restriction in the intake. At full throttle the gauge read ambient. My conclusion is that neither the ribbon (backfire flame arrestor) nor the air filter restrict the flow and are not worth removing or modifying.
Looks like 42mph on the connext and 40 on the GPS are my top speed.

 

[FSH 210 Sport]

I tried NGK Iridium plugs gapped at both the min and max gap. No difference in top speed.
As an aside, I connected a vacuum gauge manifold absolute pressure port of one engine to see if there is any restriction in the intake. At full throttle the gauge read ambient. My conclusion is that neither the ribbon (backfire flame arrestor) nor the air filter restrict the flow and are not worth removing or modifying.
Looks like 42mph on the connext and 40 on the GPS are my top speed.

What cfm did you check it at?

 

[TeenGee]

Full throttle.
7,200 rpm.
No flowmeter installed. 7,200 rpm * 1,050 cc / 2 at atmospheric pressure =~ 133.5 cfm

 

[TeenGee]

As another aside,
DON"T OVER TORQUE YOUR SPARK PLUGS.
There I said it. I sheared/pulled the threads off one of the plugs. left the threads in the hole and the rest of the plug came out in the socket.
Fortunately, I put never seize on before installation. After much anxiety and hand wringing, the threads came out easily with an EZ-Out. It took longer to drive to the parts store than to remove the broken plug.

 

[FSH 210 Sport]

You won't get to 8000, no one does. 7200-7500 is about it. Depending on engines, altitude and temperature. Check your oil levels. Should be half way between L and midway. so about a 1/4" or a bit more above L

In the spring in the great lakes, cold water cold air I have gotten 7,700 7500 now I get 7.300 7,500. One side will always be higher than the other.

Engines are sensitive to air pressure, humidity and Temperature. IF you are running in humid conditions knock a couple few hundred RPM's off. When I was down in Destin last month I lost a couple hundred RPM's a motor.

There has been a post or two of people hitting 8000 but most have never seen that. Not sure why that is.

Im pretty sure these engines are dyno tested at standard atmospheric conditions at sea level, 59°, 0% humidity, 29.92Hg. As temperature, humidity increase, and baro pressure decreases the performance of normally aspirated engines decreases.

This is a handy calculator to determine density altitude. density altitude calculator

Just use the NWS info from your local forecast and input the values to get the density altitude, and the resulting decrease in air density / hp output. Also, it is my understanding running in salt water, which is denser than fresh water, also pulls the engine performance down.

I spent a bit of time getting my high altitude impellers dialed in for my main area of operation at 5000’. On most days during the summer I’m getting 7500 rpm, if I go to one of the other local lakes which is at 2963’ I get just a hair under 8000 rpm. I haven’t been over to east river ( Missouri River) yet which is at 1200’, I have no doubt I’ll be under propped so to speak and on the limiters at wot, if I was going to be at that altitude for a longer period of time I’d put my matched oem impellers back in for that trip. For me and where I spend the majority of my time, the high altitude impellers I have are the best compromise for fishing and cruising. I lost between .3-.5 mpg with the high altitude impellers but gained a lot of top end performance. Depending on conditions I’m getting right at 3 mpg (9 gph & 27 mph) now with full fuel, full live well, gear and one person on board.

What are you seeing in terms of mpg?

 

[FSH 210 Sport]

As another aside,
DON"T OVER TORQUE YOUR SPARK PLUGS.
There I said it. I sheared/pulled the threads off one of the plugs. left the threads in the hole and the rest of the plug came out in the socket.
Fortunately, I put never seize on before installation. After much anxiety and hand wringing, the threads came out easily with an EZ-Out. It took longer to drive to the parts store than to remove the broken plug.

Did you go buy a lottery ticket? Lol! Glad to hear that there was a happy ending to that story!

 

[TeenGee]

Im pretty sure these engines are dyno tested at standard atmospheric conditions at sea level, 59°, 0% humidity, 29.92Hg. As temperature, humidity increase, and baro pressure decreases the performance of normally aspirated engines decreases.

This is a handy calculator to determine density altitude. density altitude calculator

Also, it is my understanding running in salt water, which is denser than fresh water, also pulls the engine performance down.

What are you seeing in terms of mpg?

I figured it was a combination of density altitude and salt water density. I'm at sea level and mid to upper 80's ºF. I am expecting an rpm increase when the temperatures cool or if I run in fresh water.
Fuel consumption is mid 9's - 10 GPH at 6,000 rpm and 30 mph. 4 SOB, 3/4 fuel, 200# gear, trim tabs active.

 

[TeenGee]

Did you go buy a lottery ticket? Lol! Glad to hear that there was a happy ending to that story!

Is there a club (like the Sucked a Rope) for broken plugs?

 

[FSH 210 Sport]

Full throttle.
7,200 rpm.
No flowmeter installed. 7,200 rpm * 1,050 cc / 2 at atmospheric pressure =~ 133.5 cfm

Thanks for the time and effort to verify with instrumentation there is nothing to be gained by modifying the intake tract! That’s awesome!

When I was checking out tuners, increase in air flow etc one of the main performance outfits told me there was nothing to be gained by removing the ribbon / backfire screen.

Having said that, several weeks back on a hot day, 100°, I made two wot passes across my local lake, stopped and pulled the air cleaners and made two more passes. I picked up 200 rpm without the air filters. These are the original air filters. I ordered a set of RIVA K&N drop in replacement air filters, but like many other companies they are struggling to get them made, they are two months behind so far, hoping they come in soon.

While our 1050cc engines don’t produce a lot of power, they do offer the best economy. The 210 FSH gets the best mpg of the fleet of the Yamaha boats at 3.5 mpg in the most favorable test conditions. The best I’ve seen with my boat was 3.3 on a 1.5 hour cruise, 5 people on board, and full fuel at 3900’ with the stock impellers.

 

[FSH 210 Sport]

Is there a club (like the Sucked a Rope) for broken plugs?

Not that I know of… @lazergeek is the last one I know of that had that happen and he was not as fortunate as you. The head had to come off in his case.

 

[Stubok]

@FSH 210 Sport Looks like in your situation you were able to benefit from less intake side pressure drop. Have the K&N filters proven worthwhile?

If you are able to get to 8000rpm that’s 148CFM, so a little more than 10% increase in airflow than @TeenGee needed at 7200rpm. All things being equal the pressure drop across the filter wouldn’t have increased linearly, but rather the extra 14.5CFM would have come with more than a 10% increase in pressure drop. Although now that I think about it, you have a higher specific volume (~16cuft/lb) at your 5000ft vs his (~14cuft/lb) at 1000ft, and so the mass flow was probably close (9.5lbs/min).

still it’s interesting to me that there was no vacuum at 7200rpm / 133.5CFM.

I’m going to play around with the pump side pressure drop using lucky13 cones this spring and see what, if any, benefit there is.

Thanks for the time and effort to verify with instrumentation there is nothing to be gained by modifying the intake tract! That’s awesome!

When I was checking out tuners, increase in air flow etc one of the main performance outfits told me there was nothing to be gained by removing the ribbon / backfire screen.

Having said that, several weeks back on a hot day, 100°, I made two wot passes across my local lake, stopped and pulled the air cleaners and made two more passes. I picked up 200 rpm without the air filters. These are the original air filters. I ordered a set of RIVA K&N drop in replacement air filters, but like many other companies they are struggling to get them made, they are two months behind so far, hoping they come in soon.

While our 1050cc engines don’t produce a lot of power, they do offer the best economy. The 210 FSH gets the best mpg of the fleet of the Yamaha boats at 3.5 mpg in the most favorable test conditions. The best I’ve seen with my boat was 3.3 on a 1.5 hour cruise, 5 people on board, and full fuel at 3900’ with the stock impellers.

Full throttle.
7,200 rpm.
No flowmeter installed. 7,200 rpm * 1,050 cc / 2 at atmospheric pressure =~ 133.5 cfm

 

[FSH 210 Sport]

The K&N filters did not show up before the boat got put away for its winter nap….

It should be very perky when it hits the water in spring when air temps are likely to be in the 20’s to 30’s and water temp will be in the mid 30’s.

I appreciate the CFM and specific air volume numbers as well!

Good luck with the cones!

 

[Yammi]

The K&N filters did not show up before the boat got put away for its winter nap….

It should be very perky when it hits the water in spring when air temps are likely to be in the 20’s to 30’s and water temp will be in the mid 30’s.

I appreciate the CFM and specific air volume numbers as well!

Good luck with the cones!

FSH 210 Sport,

Do you have a part # for those K&N air filters?

 

[FSH 210 Sport]

FSH 210 Sport,

Do you have a part # for those K&N air filters?

Here you go!

RIVA Yamaha EX/EXR/VX/JetBlaster (TR-1) Replacement Performance Air Filter

Our RIVA Yamaha EX/VX (TR-1 engine) Replacement Performance Air Filter directly replaces the stock paper element delivering performance through greatly improved air flow without sacrificing filtration or reliability.

rivaracing.com